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PurposeOperating in a variety of countries, multinational companies (MNCs) experience a high variety and variability of physiological and contextual dynamics, requiring a more careful knowledge management approach. In this scenario, this paper aims to investigate the entrepreneurial facets and managerial aspects (entrepreneurial orientation/managerial intentionality) of MNCs’ internationalization from a knowledge-based perspective.Design/methodology/approachA theory-building approach is applied, involving a comparative case study of two MNCs conceived through the separation of a unique family business. Aiming to enrich the research about companies’ internationalization, some crucial elements are individuated to build a theoretical frame explaining the evolutionary paths of so-called born global.FindingsThis paper shows that companies’ internationalization development is based on a multiplicity of variables and underlines the need to incorporate different points of view when attempting to explain the dynamics of internationalization processes.Research limitations/implicationsThe empirical significance of the two cases does not legitimize theorization. However, this research presents interesting results that could be strengthened by a series of comparative case studies dealing with other MNCs or deeper quantitative investigation.Originality/valueThis research approach could be considered as stimulating by the scientific and managerial community, as the internationalization process is articulated by mixing managerial, entrepreneurial and cognitive aspects.

Maintenance represents a critical aspect of manufacturing systems. Its optimization may lead companies to save costs related to production losses and can extend the whole lifecycle of assets or components. This paper aims at proposing a methodology for evaluating the behavior of systems for maintenance purpose by means of analysis carried out on real vibration data collected in the work environment. To this purpose, a digital twin approach has been developed and the statistical method of the control charts has been integrated to conduct the analysis about the vibration data. The methodology has been applied to a real case study in order to analyze the behavior of an electric motor used in the industrial sector and the results show that the method is effective in predicting possible failures that can lead to apply preventive maintenance actions.

In the context of tourist attractions, cultural heritage organizations such as museums need to innovate their services to remain competitive. Most of them are re-inventing the museum experience to broaden their attractiveness (e.g., Batat, 2020). Information and communication technologies are adopted to enhance the customer experience (e.g., Neuhofer et al., 2014) before, during, and after the visit (Shaw and Ivens, 2002). In addition to computers, tablets, interactive websites, social media, smartphones, and mobile applications, augmented reality, virtual reality, and mixed reality are applications widely used to make museums more attractive (e.g., Errichiello et al., 2019; Roederer et al., 2020; Wu et al., 2021; Bird et al., 2022; Trunfio et al., 2022). Also, multimedia technologies are developing in museums. Notably, museum exhibitions (e.g., Capuano et al., 2016) have begun to use both audio-visual and interactive technology (e.g., touch screen experience, virtual reality technology, and interactive display) to enhance the visitors’ experience (e.g., Batat, 2020; Luo, 2020). Immersive multimedia exhibitions are a specific type of museum exhibition that aims to enhance the interactive experience of the audience to disseminate knowledge and culture. More precisely, these exhibitions are based on video mapping and its various declinations: digital images, light effects, and soundtracks are designed ad hoc to be projected and spread in a physical space where the visitor moves. Some exhibitions revolve around individual artists, such as Imagine van Gogh, which was first held in Paris in 2017, and later in Canada, the USA, South America, and Europe. In this case, the artist's most famous artworks are projected in huge halls, in motion, and accompanied by the music of influential composers such as Mozart and Bach. Other immersive exhibitions use Digital Art to allow visitors to interact with digital installations in real-time. In this case, visitors look at more than just the artworks in the museum but create new ones during each visit. One example is Future World, a permanent exhibition at the ArtScience Museum in Singapore, where immersive and incredibly interactive installations react to the presence or touch of visitors, who enjoy admiring, touching, or drawing depending on the rooms visited. These exhibitions provide unique and memorable experiences for their visitors. However, not all customers can enjoy them. Mainly, some kinds of immersive experiences are not accessible to disabled people because the space, installations, and the employed technology do not meet their specific needs. In such circumstances, the adopted technology does not marry the criteria of inclusiveness of marginalized and disabled communities, opening a new debate about the role that the latest technologies should provide in developing inclusive and equitable experiences. Accordingly, based on individual impairments, disabled people cannot fully enjoy their visit to immersive multimedia exhibitions. Previous studies that have so far examined the accessibility and inclusion of disabled people in museums are very few. For example, Vaz (2020) proposed a framework that combines sensory, intellectual, and physical access into the pre-visit, on-site visit, and post-visit phases of interaction with cultural institutions to promote a sense of autonomy across these people. Furthermore, scholars and practitioners should pay more attention to the role of technology (e.g., Freeman et al., 2016) and, even more, to the adoption of immersive technologies in this research field. In this last regard, Loureiro and colleagues (2019) argued the importance of reducing the negative impacts of tourism using immersive technologies by investing in alternative accessible experiences such as virtual museum experiences. Accordingly, as Devile and Kastenholz (2018) claimed, more inclusive approaches to museums can be provided to promote individual and social well-being. Indeed, the International Council of Museums (ICOM) establishes that museums invest in safeguarding and communicating their collections to the audience and performing social functions that are the core of their existence. Therefore, further theoretical and empirical research is needed about issues related to inclusiveness and accessibility, which can concern millions of people worldwide because of temporary or permanent impairments during their lifetime. Considering these research gaps, this study focuses on the following research question: How can technology foster inclusiveness and accessibility of disabled people in immersive multimedia exhibitions? This study aims to answer this question by exploring a case study engaged in good practice in Italy. Notably, it aims to examine opportunities and barriers to inclusiveness and accessibility emerging from (desire to) attend an immersive multimedia exhibition. In terms of data collection, we will interview museum managers to explore these specific aspects and propose solutions devoted to more inclusiveness and accessibility that could serve as a starting point for designing future immersive multimedia exhibitions. The results of this research have theoretical, managerial, and social implications that are included in the perspective of Society 5.0 development.

This paper characterizes the actual science performance of the James Webb Space Telescope (JWST), as determined from the six month commissioning period. We summarize the performance of the spacecraft, telescope, science instruments, and ground system, with an emphasis on differences from pre-launch expectations. Commissioning has made clear that JWST is fully capable of achieving the discoveries for which it was built. Moreover, almost across the board, the science performance of JWST is better than expected; in most cases, JWST will go deeper faster than expected. The telescope and instrument suite have demonstrated the sensitivity, stability, image quality, and spectral range that are necessary to transform our understanding of the cosmos through observations spanning from near-earth asteroids to the most distant galaxies.

Aims. To examine mortality risk and causes of death in a cohort of a population of patients treated for gambling disorders in northern Italy from 1992 to 2019. Methods. Cohort study. Results. Half of the patients were diagnosed with psychiatric disorders, substance use disorder or alcohol dependence. The excess mortality compared to the general population (SMR) was 1.16 (0.85-1.58), more elevated among females aged 40 to 59 and males aged 20 to 29. Females had higher SMRs for all cancers and suicide; males for malignant neoplasm of liver, of lung, of prostate, and of bladder. Conclusions. Despite patients increasing, subjects who most turn to the services are the most serious ones, in older age, with comorbid mental disorders and with a compromised health status. This is reflected in the high risk of death for all cancers.

Airworthiness authorities require that composite materials in primary structures must be undamaged all in-service life long, resulting in an oversizing of structural components and in a general increasing of weight. To allow structures working in presence of damages but showing an acceptable residual strength, in recent years a significant interest has been pointed out in the capability of ultrasonic guided waves as candidate tool for Structural Health Monitoring (SHM) of composites. The continuous assessment of the structural integrity, that can be accomplished by means of SHM systems, would provide, in fact, a less-conservative design and significant benefits in repair operations. In this work, a description of two numerical techniques based on Finite Element Method (FEM) for the simulation of Lamb wave propagation in a damaged Glass Fibre Reinforced Polymer composite winglet is presented. The interaction between damage and guided-waves has been investigated under two central frequencies: 100 kHz and 150 kHz. Root Mean Square Deviation Damage Index has been used to compare the baseline signals (achieved under the pristine configuration) and the respective signals achieved under the impacted/damaged one. Numerical models have been assessed against an experimental tests campaign.

This is a multicenter study performed in two Italian tertiary care centers: General Emergency Surgery Unit at St. Orsola University Teaching Hospital - Bologna and Department of Surgical Sciences at Umberto I University Teaching Hospital - Rome. The aim was to compare the results of different approaches among elderly patients with acute bowel ischemia.Sixty-three patients were divided in two groups: 1) DSgroup- 28 patients treated in Vascular Unit and 2) GEgroup- 35 patients treated in Emergency Surgery Unit.Mean age was 80 years, significantly higher for the GEgroup (p0.001). Gender was predominantly female in both groups, without statistical difference. Pre-operatively, laboratory tests didn't show any difference in white blood cell count, serum lactate levels or serum creatinine among patients, while increase of c-reactive protein was observed in DSgroup with significant difference (p0.001). The Romamain cause of acute bowel ischemia was embolism in DSgroup (p=0.03) and vascular spasm in GEgroup (p0.001). On CT scan, bowel loop dilation was present in 58.7% of patients without statistical difference in both groups. The time lapse from diagnosis to operation didn't show significant differences between two groups (mean 349.4 min). Pre-operative heparin therapy was administered in DSgroup more frequently (p0.001). Among DS patients, thrombectomy was the most frequent procedure (19 patients) associated with bowel resection in 9 cases. In GEgroup, 22 patients had an explorative laparotomy (p0.001), 8 had a bowel resection with anastomosis and 5 a bowel resection plus stoma. A second look was required more significantly in DSgroup (p0.002). Post-operative morbidity affected significantly GEgroup (p=0.02). The 3-day survival was significantly higher in the DSgroup (p0.001). At discharge 32 patients (50.8%) were alive, 21 in DSgroup (p0.001). Only one patient among both groups (1.6%) developed a short bowel syndrome.In octogenarian patients with acute bowel ischemia, surgery should be always pursued whenever the interventional radiology is not assessed as a viable option. Both groups of patients showed an excellent outcome in terms of avoiding a short bowel syndrome. A multidisciplinary management by a dedicated team could offer the best results to prevent large intestinal resections.

In this work, two numerical procedures based on Finite Elements Method (FEM) have been developed in order to simulate the Lamb wave propagation in Low Velocity Impact (LVI) damaged CFRP (Carbon Fibre Reinforced Polymer) laminate. The former (softening representation), usually adopted in literature, consists of modelling LVI damages by lowering the elastic material properties which allowed investigating the Lamb wave propagation at different stages of LVI damages evolution. The latter, proposed in this paper, conversely to the first one and the most of techniques presented in literature, consists of simulating Lamb wave propagation in a plate characterized by an initial stress-strain state and the related failures carried out by a previous impact simulation involving the same model. Such technique allows a better damage modelling and, consequently, overcoming the damage modelling approximations introduced by the former strategy; the lowering of the elastic material properties leads to a bad damage modelling which does not allow reproducing accurately what happens in the reality. Such procedure allowed investigating the Lamb wave propagation at different impact energy levels. The interaction between Lamb waves and damages has been investigated under three central frequencies of the actuation signal: 150 kHz, 200 kHz and 250 kHz which resulted in interesting observations to minimize the effect of the first lamina's fibres orientation on the wave propagation velocity. It is well known that different wave propagation velocities along fibres and matrix lead to different RMSD (Root Mean Square Deviation) damage index values, even if the sensors are mounted at the same distance from the damage location, resulting in wrong or less accurate information about the identification of both damage size and location during the post-processing phase. Moreover, the relationships between the RMSD damage index values, recorded at different instants of time of the impact history, and the impactor phases has been achieved. Finally a comparison between the results achieved by the two investigated strategies has been carried out and presented here.

Environmental pollution, economic over-exploitation of natural resources, and growing social and economic inequalities have attracted academicians and practitioners’ interest on the role of firms as actors able to influence societal and environmental dynamics trough the economic flows. Since the preliminary definition of Corporate Social Responsibility (CSR) provided by Robert Edward Freeman in 1984, a challenging debate has attracted multiple research streams in order to depict the role of firms in social, environmental, and economic balance for a sustainable development. With the aim to enrich the ongoing debate, the paper focuses the attention on the Hofstede’s cultural dimensions as a way for depicting elements and variables able to influence firms’ commitment in CSR strategies. Six propositions are formulized for investigating the relationships between firms’ commitment to CSR and Hofstede’s cultural dimensions from managerial point of view and they are discussed with reference to the Italian firms. Secondary data from Hofstede insight platform (https://www.hofstede-insights.com/product/compare-countries/) are collected and discussed for tracing possible implications and future directions for researchers and practitioners interested in the domain of CSR in Italy.

The aim of this study was to examine the mortality trends and causes of death in Northern Italy in a cohort of a population of individuals treated for alcohol use disorder (AUD) over a 38-year follow-up period (1978-2016).6,198 patients attending eighteen centres for addiction treatment (CATs) for AUD were recruited.During the follow-up period, 19.5% of the whole cohort died. The crude mortality rates (CMRs) were elevated (21.34 x 1000 person-years [PY]), higher for men and increasing with age group. The CMRs were higher for all cancers, followed by digestive system diseases, diseases of the circulatory system, transport accidents, and suicide. The standardised mortality ratios (SMRs) were at least three times higher for women and for men, and they were more elevated in younger patients and have been falling since 2009. Multivariate analysis confirmed that the mortality risk was higher for males and increased with age and decreased over time. The patients' main characteristics changed over time and, along with a greater presence of women and non-natives, fewer marginalised people and more socially integrated people turned to CATs.The mortality risk in treated AUD is confirmed to be higher when compared with the general population, although it is decreasing. In addition, there is enough epidemiological data to assert that, independent of age and gender, the major causes of death in AUD patients are cancers, gastrointestinal disease, cardiovascular disease (CVD), and injuries.

Harmful and hazardous alcohol consumption is one of the most significant public health problems in Italy and Europe. Habitual excessive consumption and occasional excessive consumption, known as binge drinking, are the two main risk behaviours related to alcohol. Harmful drinking and alcohol dependence have strong social repercussions in terms of their social and economic impact and contribution to productivity losses. In addition, the terms alcohol abuse and alcohol dependence have been recently substituted by the only term of alcohol use disorder (AUD). The issues presented in this review demonstrate that excessive alcohol consumption is a growing public health concern and an appropriate national action plan is needed to increase the prevention of harmful and hazardous consumption and encourage patients to seek healthcare. To date, the main problem is the under-treatment of the population at risk, manifested as the time-lag between the onset of AUD and the first clinical detection. In order to address this, the Screening, Brief Intervention, and Referral to Treatment (SBIRT) strategy has been shared across countries in Europe and is supported by a Systematic Review of Reviews on SBIRT in primary healthcare. Unfortunately, there are still obstacles in the implementation of this approach. The main problem would appear to be general practitioners' difficulty in carrying out accurate and widespread screening, because they may minimize the problem. A more concerted effort in the training of healthcare professionals could address this by enabling the creation of renewed networks for the early identification of harmful and hazardous drinkers. These networks could prevent the occurrence of avoidable alcohol-related conditions, such as alcohol-related liver disease (ALD), while allowing for the timely implementation of evidence-based brief interventions.

[This corrects the article DOI: 10.1155/2019/8691502.].

In 2015, Wienhofena et al. stated that “Big Data is a collection of large data sets with a great diversity of types so that it becomes difficult to process by using state-of-the-art data processing approaches or traditional data processing platforms” (pag. 1). Recognizing the validity of this definition and its implications for all social, economic, and environmental domains, it is possible affirm that Big Data can be considered a disruptive change in the way in which individuals, organisations and whole ecosystems perceive the world and react to their stimuli and dynamics (Chai and Shih, 2017; Swan, 2013). Following these reflections, the paper focuses the attention on the healthcare domain with the aim to: 1] provide a general overview of the key concepts on which Big Data are based in the light of health management perspectives and 2] trace possible advancements in knowledge for the management of Big Data in the healthcare domain. Adopting a systems view, a multiple case studies based on four different scenarios is proposed as approach for investigating the contribution of Big Data in increasing the effectiveness of healthcare management.

Kidney transplantation (KT) may restore fertility in chronic kidney disease (CKD). The reasons why maternofetal outcomes are still inferior to the overall population are only partially known. Comparison with the CKD population may offer some useful insights for management and counselling.Aim of this study was to analyse the outcomes of pregnancy after KT, compared with a large population of nontransplanted CKD patients and with low-risk control pregnancies, observed in Italy the new millennium.We selected 121 live-born singletons after KT (Italian study group of kidney in pregnancy, national coverage about 75%), 610 live-born singletons in CKD, and 1418 low-risk controls recruited in 2 large Italian Units in the same period (2000-2014). The following outcomes were considered: maternal and fetal death; malformations; preterm delivery; small for gestational age (SGA) baby; need for the neonatal intensive care unit; doubling of serum creatinine or increase in CKD stage. Data were analyzed according to kidney diseases, renal function (staging according to CKD-epidemiology collaboration), hypertension, maternal age, parity, ethnicity.Maternofetal outcomes are less favourable in CKD and KT as compared with the low-risk population. CKD stage and hypertension are important determinants of results. Kidney transplantation patients with estimated glomerular filtration rate greater than 90 have worse outcomes compared with CKD stage 1 patients; the differences level off when only CKD patients affected by glomerulonephritis or systemic diseases ("progressive CKD") are compared with KT. In the multivariate analysis, risk for preterm and early-preterm delivery was linked to CKD stage (2-5 vs 1: relative risk 3.42 and 3.78) and hypertension (RR 3.68 and 3.16) while no difference was associated with being a KT or a CKD patient.The maternofetal outcomes in patients with kidney transplantation are comparable with those of nontransplanted CKD patients with similar levels of kidney function impairment and progressive and/or immunologic kidney disease.

According to many studies, extracorporeal dialysis with convective methods is associated with better clinical outcomes and a survival benefit compared to diffusive techniques. However, there is no full agreement on the actual superiority of this kind of renal replacement therapy on hard end-points such as mortality. We performed a retrospective epidemiological cohort study to provide "real-world" evidence on the impact of convective and non-convective dialysis techniques on all-cause and cardiac mortality and biochemical outcomes among dialysis patients in Sicily, the southernmost region of Italy. Data of all incident adult patients (N = 6529) who have started chronic extracorporeal dialysis over the period 2009-2015 were retrieved from the Sicilian Registry of Nephrology, Dialysis and Transplantation. There were 1558 patients receiving convective techniques (23.86%). Overall mortality rate was 45.21% with a significant difference between convective (31.39%) and non-convective (49.55%) groups (P 0.0001). After adjustment for potential confounders in multiple Cox regression models of increasing complexity, the mortality risk remained significantly lower for patients treated with convective methods (HR, 0.581; 95%CI, 0.525 to 0.643; P 0.0001). Moreover, the convective group had a better blood chemistry profile, improved dialysis efficacy, and reduced mortality rate from cardiac diseases compared to the non-convective group. As a sensitivity analysis, patients were categorized according to propensity score quartiles and the hazard ratio for both all-cause and cardiac mortality was significantly lower for the convective group in each quartile. In conclusion, despite the observational and retrospective design, the results of the present study further support the use of convective therapies for the treatment of end-stage renal disease.

Napoli - Italia

New Orleans, Louisiana, USA.

We present a detailed analysis of theoretical period–luminosity (PL) and period–luminosity–color (PLC) relations of classical Cepheids, as derived from nonlinear, nonlocal, time-dependent convective pulsating models with different masses and chemical compositions. The predicted PL and PLC relations turn out to depend on the pulsator metallicity and, to a minor extent, on the adopted averages (magnitude-weighted or intensity-weighted) over the light cycle in different bands. We show that the determination of the reddening and true distance modulus of a galaxy from the observed PL and PLC relations is constrained by the metallicity sensitivity of these relations. Moreover, the metallicity sensitivity itself provides us with a powerful tool for deriving self-consistent evaluations of distance, reddening and metallicity of the host galaxy, once Cepheid measurements in at least three photometric bands are available. To illustrate this point, we apply our relations to the BVK data for Cepheids in the Magellanic Clouds, assuming to be unaware of their metallicities. The three filter method is finally adopted to evaluate the metallicity of galactic Cepheids (BVI data) as a function of their position.

We present new UBV I CCD observations of the old LMC globular cluster RETICULUM. These data allowed us to re-determine periods and light curves and to identify 4 double mode RR Lyrae stars. A comparison with the theoretical instability strip in the MV − logP plane shows good agreement between theory and observations when an apparent distance modulus of (m−M)=18.45±0.12 mag (i.e.(m−M)0=18.39±0.12 mag) is assumed.

Naples, Italy

Valenciennes, Francia.

Lucca

Metadoxine is approved in Europe for alcohol intoxication and is also indicated for alcoholic liver disease (ALD). This study aims to investigate the use of metadoxine as a potential pharmacotherapy for alcohol dependence (AD).This is a retrospective study of 94 outpatients with AD, who received metadoxine for alcohol intoxication and were assessed for alcohol consumption, craving [Visual Analog Scale (VAS)] and liver-related and alcohol-related biomarkers [aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma-glutamyl-transpeptidase, mean corpuscular volume].Range of metadoxine dose was 500-2000 mg/day, with a mean dose of 1277(s.d.290) mg/day, and for a period of 2-42 days, with a mean period of 8.9(s.d.7.0) days. Follow-up data were available for 52 patients (55.3%); 35(67.3%) patients were completely abstinent. There was a significant decrease in drinks per week, even after substituting baseline drinking as follow-up data for dropouts (p 0.001) and examining drinking pre-treatment and post-treatment for those who did not achieve abstinence (p 0.001). There was a significant decrease in the VAS (p 0.001) and a significant improvement in the AST/ALT ratio (p = 0.03).Despite important limitations, this study represents a further preliminary observation suggesting metadoxine as a novel alcohol pharmacotherapy, including in alcohol-dependent patients with ALD.

Palermo - Italy

Silesian University of Technology, Gliwice, POLAND

We present new empirical estimates of the Delta V_HB_bump parameter for 15 Galactic globular clusters (GGCs) using accurate and homogeneous ground-based optical data. Together with similar evaluations available in the literature, we ended up with a sample of 62 GGCs covering a very broad range in metal content (-2.160), might be systematically smaller than predicted.

We present U,B,V,I photometry of the Carina dwarf spheroidal galaxy, based on more than 4,000 CCD images. Special attention was given to the photometric calibration, and the precision for the B,V,I bands is better than 0.01 mag. We compared in the V,B-V and V,B-I color-magnitude diagrams (CMDs) Carina with three Globular Clusters (GCs, M53, M55, M79). We find that only the more metal-poor GCs (M55, [Fe/H]=-1.85; M53, [Fe/H]=-2.02 dex) provide a good match with the Carina giant branch. We performed a similar comparison in the V,V-I CMD with three SMC intermediate-age clusters (IACs, Kron3, NGC339, Lindsay38). We find that the color extent of the SGB of the two more metal-rich IACs (Kron3, [Fe/H]=-1.08; NGC339, [Fe/H]=-1.36 dex) is smaller than the range among Carina's intermediate-age stars. However, the ridge line of the more metal-poor IAC (Lindsay38, [Fe/H]=-1.59 dex) agrees quite well with the Carina intermediate-age stars. These findings indicate that Carina's old stellar population is metal-poor and seems to have a limited spread in metallicity (Delta [Fe/H]=0.2--0.3 dex). Carina intermediate-age stars can hardly be more metal-rich than Lindsay38 and its spread in metallicity appears modest. We also find that the synthetic CMD constructed assuming a metallicity spread of 0.5 dex for intermediate-age stars predicts evolutionary features not supported by observations. The above results are at odds with recent spectroscopic investigations suggesting that Carina stars cover a broad range in metallicity (Delta [Fe/H]~1--2 dex). We present a new method to estimate the metallicity of complex stellar systems using the difference in color between the red clump and the middle of the RR Lyrae instability strip. The observed colors of Carina's evolved stars indicate a metallicity of [Fe/H]=-1.70+-0.19 dex, which agrees quite well with spectroscopic measurements., Accepted on PASP, 12 pages, 6 figures

We present deep and accurate Near-Infrared (NIR) photometry of the Galactic Globular Cluster (GC) Omega Cen. Data were collected using the Multi-Conjugate Adaptive Optics Demonstrator (MAD) on VLT (ESO). The unprecedented quality of the images provided the opportunity to perform accurate photometry in the central crowded regions. Preliminary results indicate that the spread in age among the different stellar populations in Omega Cen is limited.

Vico Equense (NA) - Italia

We perform a detailed analysis of Cepheids in NGC 4258, Magellanic Clouds and Milky Way in order to verify the reliability of the theoretical scenario based on a large set of nonlinear convective pulsation models. We derive Wesenheit functions from the synthetic BVI magnitudes of the pulsators and we show that the sign and the extent of the metallicity effect on the predicted Period-Wesenheit (P-W) relations change according to the adopted passbands. These P-W relations are applied to measured BVI magnitudes of NGC 4258, Magellanic and Galactic Cepheids available in the literature. We find that Magellanic and Galactic Cepheids agree with the metallicity dependence of the predicted P-W relations. Concerning the NGC 4258 Cepheids, the results strongly depend on the adopted metallicity gradient across the galactic disc. The most recent nebular oxygen abundances support a shallower gradient and provide a metallicity dependence that agrees well with current pulsation predictions. Moreover, the comparison of Cepheid distances based on VI magnitudes with distance estimates based on the revised TRGB method for external galaxies, on the HST trigonometric parallaxes for Galactic Cepheids, and on eclipsing binaries in the Magellanic Clouds seems to favor the metallicity correction predicted by pulsation models. The sign and the extent of the metallicity dependence of the Period-Wesenheit and of the Period-Luminosity relations change according to the adopted passbands. Therefore, distances based on different methods and/or bands should not be averaged. The use of extragalactic Cepheids to constrain the metallicity effect requires new accurate and extensive nebular oxygen measurements., Comment: accepted for publication on ApJ

We present an updated and homogeneous pulsational scenario for a wide range of stellar parameters typical of BL Her stars i.e., Population II Cepheids with periods shorter than 8 days., Comment: 3 pages, 2 greyscale figures. Proceedings of the workshop "XXI Century challenges for stellar evolution", held in Cefalu' (Sicily, Italy), August 29 - September 2, 2007; S. Cassisi and M. Salaris Eds. To be published in Mem. SAIt Vol. 79 No. 2

We performed a new calibration of the Stroemgren metallicity index m1 based on the b-y color of cluster red giant stars. The current Metallicity-Index-Color relation is not linear in the color range 0.40 < b-y < 1.0, but provides iron abundances of cluster and field red giants with an accuracy of ~ 0.25 dex., 3 pages, 2 figures; to appear in Mem. Soc. Astr. Italiana, Vol. 79/2 (proceeding Cefalu' Workshop "XXI Century Challenges for Stellar Evolution", ed. S. Cassisi & M. Salaris)

We present new empirical and theoretical calibrations of two photometric metallicity indices based on Walraven photometry. The empirical calibration relies on a sample of 48 Cepheids for which iron abundances based on high resolution spectra are available in the literature. They cover a broad range in metal abundance (-0.5 < [Fe/H] < +0.5) and the intrinsic accuracy of the Metallicity Index Color (MIC) relations is better than 0.2 dex. The theoretical calibration relies on a homogeneous set of scaled-solar evolutionary tracks for intermediate-mass stars and on pulsation predictions concerning the topology of the instability strip. The metal content of the adopted evolutionary tracks ranges from Z=0.001 to Z=0.03 and the intrinsic accuracy of the MIC relations is better than 0.1 dex., 6 pages, 5 figures; to appear in Mem. Soc. Astr. Italiana, Vol. 79/2 (proceeding Cefalu' Workshop "XXI Century Challenges for Stellar Evolution", ed. S. Cassisi & M. Salaris)