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Multivalent vaccines addressing an increasing number of Streptococcus pneumoniae types (7-, 10-, 13-, 15-, 20-valent) have been licensed over the last 22 years. The use of polysaccharide-protein conjugate vaccines has been pivotal in reducing the incidence of invasive pneumococcal disease despite the emergence of non-vaccine serotypes. Notwithstanding its undoubtable success, some weaknesses have called for continuous improvement of pneumococcal vaccination. For instance, despite their inclusion in pneumococcal conjugate vaccines, there are challenges associated with some serotypes. In particular, Streptococcus pneumoniae type 3 remains a major cause of invasive pneumococcal disease in several countries.Here a deep revision of the strengths and weaknesses of the licensed pneumococcal conjugate vaccines and other vaccine candidates currently in clinical development is reported.

Group B Streptococcus (GBS) is a Gram-positive bacterium and the most common cause of neonatal blood and brain infections. At least 10 different serotypes exist, that are characterized by their different capsular polysaccharides. The Group B carbohydrate (GBC) is shared by all serotypes and therefore attractive be used in a glycoconjugate vaccine. The GBC is a highly complex multiantennary structure, composed of rhamnose rich oligosaccharides interspaced with glucitol phosphates. We here report the development of a convergent approach to assemble a pentamer, octamer, and tridecamer fragment of the termini of the antennae. Phosphoramidite chemistry was used to fuse the pentamer and octamer fragments to deliver the 13-mer GBC oligosaccharide. Nuclear magnetic resonance spectroscopy of the generated fragments confirmed the structures of the naturally occurring polysaccharide. The fragments were used to generate model glycoconjugate vaccine by coupling with CRM197. Immunization of mice delivered sera that was shown to be capable of recognizing different GBS strains. The antibodies raised using the 13-mer conjugate were shown to recognize the bacteria best and the serum raised against this GBC fragment-mediated opsonophagocytic killing best, but in a capsule dependent manner. Overall, the GBC 13-mer was identified to be a highly promising antigen for incorporation into future (multicomponent) anti-GBS vaccines.

Antimicrobial resistance (AMR) is emerging as the next potential pandemic. Different microorganisms, including the bacteria Acinetobacter baumannii, Clostridioides Pseudomonas aeruginosa, non-typhoidal Salmonella, and Staphylococcus aureus, and the fungus Candida auris, have been identified by the WHO and CDC as urgent or serious AMR threats. Others, such as group A and B Streptococci, are classified as concerning threats. Glycoconjugate vaccines have been demonstrated to be an efficacious and cost-effective measure to combat infections against Haemophilus influenzae, Neisseria meningitis, Streptococcus pneumoniae, and, more recently, Salmonella typhi. Recent times have seen enormous progress in methodologies for the assembly of complex glycans and glycoconjugates, with developments in synthetic, chemoenzymatic, and glycoengineering methodologies. This review analyzes the advancement of glycoconjugate vaccines based on synthetic carbohydrates to improve existing vaccines and identify novel candidates to combat AMR. Through this literature survey we built an overview of structure-immunogenicity relationships from available data and identify gaps and areas for further research to better exploit the peculiar role of carbohydrates as vaccine targets and create the next generation of synthetic carbohydrate-based vaccines.

Advances in the treatment and management of cystic fibrosis (CF) have led to a substantial increase in patient life expectancy, thus facilitating healthier lives and labour force participation. This review aimed to address the impact of CF on the occupational functioning of patients. A significant proportion of patients were reported to retain a job on a full- or part-time schedule. Less physically demanding occupations were most frequently performed, perhaps due to CF-related inability to sustain a heavy workload. Disease severity parameters (e.g., lung function measurements, or personal, psycho-social, or economic conditions) have been reported as determinant or co-determinant factors for the development of work-related disability. Although further research is necessary, our results may be useful to inform interdisciplinary CF healthcare management, including the assessment of work function, and to define career counselling plans and workplace risk assessment and management strategies to support the personal, social and professional lives of patients.

In many fields of applications, linear regression is the most widely used statistical method to analyze the effect of a set of explanatory variables on a response variable of interest. Classical least squares regression focuses on the conditional mean of the response, while quantile regression extends the view to conditional quantiles. Quantile regression is very convenient, whereas classical parametric assumptions do not hold and/or when relevant information lies in the tails and therefore the interest is in modeling the conditional distribution of the response at locations different from the mean. A situation common to most regression applications is the presence of strong correlations between predictors. This leads to the well-known problem of collinearity. While the effects of collinearity on least squares estimates are well investigated, this is not the case for quantile regression estimates. This paper aims to explore the collinearity problem in quantile regression. First, a simulation study analyses the problem concerning different degrees of collinearity and various response distributions. Then the paper proposes using regression on latent components as a possible solution to collinearity in quantile regression. Finally, a case study shows the assessment of the quality of service in the presence of highly correlated predictors.

Environmental sustainability is an increasingly important issue for many business and social actors. This has led many scholars to research the effects of this phenomenon from various points of view trying to understand whether green attitudes can influence consumer behaviours in sustaining consumer–brand relationships. Accordingly, this paper aims to explore the impact of green consumer values on consumer–brand relationships in driving intentional behaviour. The authors developed an empirical study based on a research framework with six latent variables and 43 manifest variables using a partial least squares-structural equation (PLS-SEM). A survey was given to a sample of Italian consumers (n = 661) to explore mobility choices from a sustainability perspective (i.e. car and motorcycle users). The main findings show that green consumption values positively impact offline and online brand responses. Moreover, the research outcomes are discussed and evaluated in terms of theoretical, managerial and policy implications. Finally, we present the main limits and future research opportunities.

The COVID-19 pandemic has affected every aspect of economic and social life, even overwhelming education. The sudden shift from face-to-face to distance learning affected the students’ learning experience. In addition to some tangible factors, such as the availability of a good connection or adequate connecting devices, several social and psychological factors may have influenced distance learning students’ perceptions. This paper aims to understand how higher education students perceived distance learning during COVID-19 and whether some socio-psychological factors, such as stress and career-related anxiety, impacted their perception. Data are collected from a survey of 1592 students from various Italian Universities and analyzed using exploratory factor analysis and partial least squares-based structural equation modelling.

In the last years, sustainability has become a successful, relevant, critical factor in several food industries. The adoption of a sustainable marketing strategy contributes positively to changes in society in terms of environmental, social and economic development. The relationship between sustainability and business performance has been widely debated in management and organisational studies. However, despite its importance and relevance, fishery sustainability has not been systematically considered by scientific studies. This paper identifies and analyses the critical factors that describe the propensity towards sustainable development for large companies within the Italian fishery sector. For this purpose, the relationships among the following latent variables were analysed: sustainable social behaviour, sustainable environmental behaviour, sustainable marketing, and return on investment. A theoretical research model has been proposed and empirically tested using a methodology based on structural equation modelling.

Recent studies have pointed out the effect of personality traits on athletes’ performance and success; however, fewer analyses have focused the relation among these features and specific athletic behaviors, skills, and strategies to enhance performance. To fill this void, the present paper provides evidence on what personality traits mostly affect athletes’ mental skills and, in turn, their effect on the performance of a sample of elite swimmers. The main findings were obtained by exploiting a component-based structural equation modeling which allows to analyze the relationships among some psychological constructs, measuring personality traits and mental skills, and a construct measuring sports performance. The partial least squares path modeling was employed, as it is the most recognized method among the component-based approaches. The introduced method simultaneously encompasses latent and emergent variables. Rather than focusing only on objective behaviors or game/race outcomes, such an approach evaluates variables not directly observable related to sport performance, such as cognition and affect, considering measurement error and measurement invariance, as well as the validity and reliability of the obtained latent constructs. The obtained results could be an asset to design strategies and interventions both for coaches and swimmers establishing an innovative use of statistical methods for maximizing athletes’ performance and well-being.

A long tradition of analysing ordinal response data deals with parametric models, which started with the seminal approach of cumulative models. When data are collected by means of Likert scale survey questions in which several scored items measure one or more latent traits, one of the sore topics is how to deal with the ordered categories. A stacked ensemble (or hybrid) model is introduced in the proposal to tackle the limitations of summing up the items. In particular, multiple items responses are synthesised into a single meta-item, defined via a joint data reduction approach; the meta-item is then modelled according to regression approaches for ordered polytomous variables accounting for potential scaling effects. Finally, a recursive partitioning method yielding trees provides automatic variable selection. The performance of the method is evaluated empirically by using a survey on Distance Learning perception.

Analyzing sports data has become a challenging issue as it involves not standard data structures coming from several sources and with different formats, being often high dimensional and complex. This paper deals with a dyadic structure (athletes/coaches), characterized by a large number of manifest and latent variables. Data were collected in a survey administered within a joint project of University of Naples Federico II and Italian Swimmer Federation. The survey gathers information about psychosocial aspects influencing swimmers’ performance. The paper introduces a data processing method for dyadic data by presenting an alternative approach with respect to the current used models and provides an analysis of psychological factors affecting the actor/partner interdependence by means of a quantile regression. The obtained results could be an asset to design strategies and actions both for coaches and swimmers establishing an original use of statistical methods for analysing athletes psychological behaviour.

Copyright © 2020 the Author(s). Published by PNAS. This open access article is distributed under Creative Commons Attribution-NonCommercial-NoDerivatives License 4.0 (CC BY-NC-ND)., Meningococcal meningitis remains a substantial cause of mortality and morbidity worldwide. Until recently, countries in the African meningitis belt were susceptible to devastating outbreaks, largely attributed to serogroup A Neisseria meningitidis (MenA). Vaccination with glycoconjugates of MenA capsular polysaccharide led to an almost complete elimination of MenA clinical cases. To understand the molecular basis of vaccine-induced protection, we generated a panel of oligosaccharide fragments of different lengths and tested them with polyclonal and monoclonal antibodies by inhibition enzyme-linked immunosorbent assay, surface plasmon resonance, and competitive human serum bactericidal assay, which is a surrogate for protection. The epitope was shown to optimize between three and six repeating units and to be O-acetylated. The molecular interactions between a protective monoclonal antibody and a MenA capsular polysaccharide fragment were further elucidated at the atomic level by saturation transfer difference NMR spectroscopy and X-ray crystallography. The epitope consists of a trisaccharide anchored to the antibody via the O- and N-acetyl moieties through either H-bonding or CH–π interactions. In silico docking showed that 3-O-acetylation of the upstream residue is essential for antibody binding, while O-acetate could be equally accommodated at three and four positions of the other two residues. These results shed light on the mechanism of action of current MenA vaccines and provide a foundation for the rational design of improved therapies., This work was sponsored by GlaxoSmithKline Biologicals and has received funding from the European Union’s Horizon 2020 Research and Innovation Programme under the Marie Skłodowska-Curie Grant Agreement 675671.

The Covid-19 pandemic forced students of any age and level of education to change the learning process, from learning in presence, to Distance Learning (DL). Such a relevant switch to DL has not been seamless for students, from both practical and psychological perspectives. In fact, students adaptation to DL process also depends on Covid-19 induced stress. Aim of the paper is to analyse an Italian university students survey on DL perception and Covid-19 related psychological effects, such as stress. The proposed approach implements a hybrid method that synthesizes the DL perception items into an ordinal response that is then regressed on the remaining items, to study the the effects on DL perception of further aspects (such as stress) and identify the most relevant covariates. The modeling phase consists of the implementation of the adjacent categories models to take into account the intensity of the opinions (students’ feeling) at each end of the spectrum.

External preference mapping is widely used in marketing and R&D divisions to understand the consumer behaviour. The most common preference map is obtained through a two-step procedure that combines principal component analysis and least squares regression. The standard approach exploits classical regression and therefore focuses on the conditional mean. This paper proposes the use of quantile regression to enrich the preference map looking at the whole distribution of the consumer preference. The enriched maps highlight possible different consumer behaviour with respect to the less or most preferred products. This is pursued by exploring the variability of liking along the principal components as well as focusing on the direction of preference. The use of different aesthetics (colours, shapes, size, arrows) equips standard preference map with additional information and does not force the user to change the standard tool she/he is used to. The proposed methodology is shown in action on a case study pertaining yogurt preferences.

Background: In the present study we evaluated the efficacy of an innovative model of HCV micro-elimination in a hospital setting in an area of high HCV prevalence.Patients and metods: Between January and December 2019, a prospective, interventional study for a program of HCV case-finding and linkage-to-care was performed in S. Anna and S. Sebastiano hospital of Caserta, in Campania, a region in southern Italy. All adult patients who were admitted to the Caserta hospital in the study period and resulted positive for anti-HCV were included in the study. The outcomes evaluated were the number of subjects resulting HCV-RNA-positive, those linked-to-care and treated with a DAA and the subjects whose anti-HCV-status was unknown.Results: In the study period, 14,396 subjects, admitted to the hospital for different reasons, were tested for anti-HCV: 529 (3.7%) subjects resulted positive for anti-HCV. Of the 529 anti-HCV-positive subjects, 10 died during hospitalization and 243 were already treated with a DAA. The remaining 276 subjects were contacted and agreed to be evaluated. Of these 276 subjects, 68 patients resulted HCV- RNA-negative and 194 HCV-RNA-positive and 180 of these were treated with a DAA according to the international guidelines.Discussion: A simple, rapid, inexpensive model of HCV micro-elimination in the hospital setting allowed us to find anti-HCV-positive subjects with unknown anti-HCV status or not linked to a clinical center. (c) 2022 The Author(s). Published by Elsevier Ltd on behalf of King Saud Bin Abdulaziz University for Health Sciences. CC_BY_NC_ND_4.0

Improvements in the survival and clinical outcomes of cystic fibrosis (CF) patients raised questions about their workforce participation and capacity to work. One hundred and ninety-six outpatients, attending the Adult CF Center of an Italian University Hospital, were enrolled between May 2020 and March 2021. The patients’ personal and clinical characteristics, employment status, and profession were assessed. The Cystic Fibrosis Questionnaire—Revised and the work ability index (WAI) were employed to assess CF health-related quality of life and the employee’s perception of their ability to work, respectively. Among the enrolled patients, 98 (50%) were employed. The non-working subjects were significantly younger (mean age ± standard deviation: 30 ± 10 vs. 37 ± 10 years) and were diagnosed with CF significantly earlier (9 ± 13 vs. 17 ± 18 years) than the employed subjects. The vast majority of CF workers (82.6%) were employed in tertiary professions. A general good work ability perception was determined in the employed population. Aging and being employed for &gt, 15 years could significantly predict a reduction in work ability, while a better quality of life was a positive predictor for its enhancement. Although further research is necessary, these results may introduce interdisciplinary CF healthcare management that includes a work function assessment, formal career counseling, and job guidance to support the personal, social and professional lives of CF patients.

This paper is about the use of the multiblock regression method sequential and orthogonalized partial least squares (SO-PLS) for path modeling. The paper is a follow up of previously published papers on the same topic and presents a number of new results for the method. First of all, the paper discusses more thoroughly the aspect of how to incorporate blocks in the models and relates this to standard concepts in the area of graphical modeling. Second, the paper defines the concept of direct and indirect effects more precisely in terms of population parameters and shows how they are related to the additional effect in SO-PLS modeling. The paper illustrates the theory by simple graphs, simulations, and a real example from process monitoring.

In the cruise industry, there has recently been a considerable increase of interest in managing the on-board servicescape by recognizing the physical environment as an important driver of competitive advantage to provide a memorable tourism experience. However, few studies have focused on this issue in the specific context of the cruise industry, and even fewer studies have used this dimension as basis for clustering passengers. Adopting an experiential marketing approach, the aim of this study was to profile cruise passengers based on their perceived on-board servicescape and experience. Exploratory factor analysis (EFA) and Hierarchical Cluster Analysis were applied to data from a sample of 417 cruise passengers interviewed in 2017 at the port of call of Naples (Italy). The EFA revealed interesting insights by disconfirming the existing literature through the identification of new latent subfactors. Four clusters profiling interesting passenger types that are useful for customizing the on-board experience were identified. Moreover, analysis of variance (ANOVA) was employed to determine whether the different types of cruisers in their response to behavioral intentions (i.e. WOM and e-WOM). The empirical findings enrich the existing literature on the cruise experience by introducing an original model of segmentation; they provide some practical insights for cruise managers to develop customized on-board service offerings. Finally, research opportunities based on these findings are also discussed.

Chronic pain is associated with cognitive deficits. Palmitoylethanolamide (PEA) has been shown to ameliorate pain and pain-related cognitive impairments by restoring glutamatergic synapses functioning in the spared nerve injury (SNI) of the sciatic nerve in mice. SNI reduced mechanical and thermal threshold, spatial memory and LTP at the lateral entorhinal cortex (LEC)-dentate gyrus (DG) pathway. It decreased also postsynaptic density, volume and dendrite arborization of DG and increased the expression of metabotropic glutamate receptor 1 and 7 (mGluR1 and mGluR7), of the GluR1, GluR1s845 and GluR1s831 subunits of AMPA receptor and the levels of glutamate in the DG. The level of the endocannabinoid 2-arachidonoylglycerol (2-AG) was instead increased in the LEC. Chronic treatment with PEA, starting from when neuropathic pain was fully developed, was able to reverse mechanical allodynia and thermal hyperalgesia, memory deficit and LTP in SNI wild type, but not in PPAR alpha null, mice. PEA also restored the level of glutamate and the expression of phosphorylated GluR1 subunits, postsynaptic density and neurogenesis. Altogether, these results suggest that neuropathic pain negatively affects cognitive behavior and related LTP, glutamatergic synapse and synaptogenesis in the DG. In these conditions PEA treatment alleviates pain and cognitive impairment by restoring LIT and synaptic maladaptative changes in the LEC-DG pathway. These outcomes open new perspectives for the use of the N-acylethanolamines, such as PEA, for the treatment of neuropathic pain and its central behavioural sequelae.

Background: Citicoline and homotaurine are compounds with a potent neuroprotective activity and they have been administered for many years in the treatment of numerous neurodegenerative and ophthalmological diseases, including glaucoma. Initially available only as liquid form, through parenteral route, nowadays citicoline can be administered also as tablet but no data on bioavailability of these different forms are available. In the present study, pharmacokinetics of citicoline in tablet versus vials, each at the therapeutic dose of 500 mg, in addition to 50 mg of homotaurine was investigated. Materials and methods: Ten mixed breed dogs received a single dose of 50 mg oral homotaurine and 500 mg citicoline in tablet and vials with the same dose were administered after a seven days wash-out period. Parameters assessed for citicoline metabolites (cytidine, uridine and choline) were AUC0−t, Cmax and Tmax. Results: Citicoline bioavailability appeared to be slightly higher for the tablet compared to the vial formulation. Cytidine is equivalent in absorption dynamics both for tablet and liquid form; uridine for tablet reaches its maximum and is reabsorbed more quickly while choline for the liquid form reaches the maximum first and is reabsorbed more quickly. Conclusions: Citicoline in tablet and liquid formulation have pharmacokinetic properties leading to a very similar bioavailability.

Despite the considerable progress toward the eradication of meningococcal disease with the introduction of glycoconjugate vaccines, previously unremarkable serogroup X has emerged in recent years, recording several outbreaks throughout the African continent. Different serogroup X polysaccharide-based vaccines have been tested in preclinical trials, establishing the principles for further improvement. To elucidate the antigenic determinants of the MenX capsular polysaccharide, we generated a monoclonal antibody, and its bactericidal nature was confirmed using the rabbit serum bactericidal assay. The antibody was tested by the inhibition enzyme-linked immunosorbent assay and surface plasmon resonance against a set of oligosaccharide fragments of different lengths. The epitope was shown to be contained within five to six α-(1–4) phosphodiester mannosamine repeating units. The molecular interactions between the protective monoclonal antibody and the MenX capsular polysaccharide fragment were further detailed at the atomic level by saturation transfer difference nuclear magnetic resonance (NMR) spectroscopy. The NMR results were used for validation of the docking analysis between the X-ray crystal structure of the antibody (Fab fragment) and the modeled hexamer oligosaccharide. The antibody recognizes the MenX fragment by binding all six repeating units of the oligosaccharide hydrogen bonding, salt bridges, and hydrophobic interactions. studies demonstrated that conjugates containing five to six repeating units can produce high functional antibody levels. These results provide an insight into the molecular basis of MenX vaccine-induced protection and highlight the requirements for the epitope-based vaccine design.

The paper presents a new insight of a recently proposed method named partial possibilistic regression path modeling. This method combines the principles of path modeling with those of possibilistic regression to model the net of relations among blocks of variables, where a weighted composite summarizes each block. It assumes that randomness can refer back as the measurement error, which is the error in modeling the relations between the observed variables and the corresponding composite, and the vagueness to the structural error, which is the uncertainty in modeling the relations among the composites behind each block of variables. The comparison of the proposed method with a classical composite-based path model is based on a simulation study. A case study on the use of Wikipedia in higher education illustrates a fruitful usability context of the proposed method.

The main objective of the consumer analysis is to analyze the heterogeneity of preferences with respect to a predefined set of products. In some cases, consumer preferences are also related to some specific drivers in order to obtain preference models to be used in planning marketing strategies. The aim of this work is to present a strategy that allows to estimate preference models taking into account the individual differences of consumers in the liking pattern. The proposed strategy consists in using quantile regression to obtain preference models for homogeneous groups of consumers with respect to the quantile that best represents them. The strategy will be tested on data deriving from a case study on consumer’s preferences for muscadine grape juices.

PurposeThis study aims to analyze the impact of event experience on event satisfaction and intentions to return and recommend the destination.Design/methodology/approachRelationships among constructs were tested on data gathered from 542 tourists during the America's Cup World Series held in South Italy in April 2013 by using a structural equation modeling approach. Moreover, a multigroup analysis was developed to test the possible moderator factors.FindingsThe results revealed that event experience and event satisfaction had positive impacts on the intentions to recommend and return to the host destination. Moreover, nationality, gender and trip motivation emerged as important moderating factors in the relationships among the latent constructs.Research limitations/implicationsThe findings of this paper enrich the existing literature and help tourism destination marketers and managers consider the triggering factors of a satisfying mega-sports event for the host destination and the marketing power of the on-site experience.Practical implicationsPractitioners should draw on the insights provided by this study to design destination strategies, particularly by paying attention to how an event experience causes an attendee to return to and recommend the host destination.Originality/valueThis study enriches the existing event literature in several ways. First, it emphasizes the importance of the event experience to the satisfaction level and willingness to return and recommend the host destination for a vacation, supporting the link between an event and its destination. Second, it provides a moderating analysis that offers new insights for marketing the event experience. It offers a multilevel model of mega-event tourism legacy, which opens up new avenues of research. Third, complementing the consumer-based analysis, this research includes the trend of visits (after 2013 to the present) to examine how a mega-sport event has brought about more postevent visits.

Identification of glycan functional epitopes is of paramount importance for rational design of glycoconjugate vaccines. We recently mapped the structural epitope of the capsular polysaccharide from type III Group B Streptococcus (GBSIII), a major cause of invasive disease in newborns, by using a dimer fragment (composed of two pentasaccharide repeating units) obtained by depolymerization complexed with a protective mAb. Although reported data had suggested a highly complex epitope contained in a helical structure composed of more than four repeating units, we showed that such dimer conjugated to a carrier protein with a proper glycosylation degree elicited functional antibodies comparably to the full‐length conjugated polysaccharide. Here, starting from the X‐ray crystallographic structure of the polysaccharide fragment–mAb complex, we synthesized a hexasaccharide comprising exclusively the relevant positions involved in binding. Combining competitive surface plasmon resonance and saturation transfer difference NMR spectroscopy as well as in‐silico modeling, we demonstrated that this synthetic glycan was recognized by the mAb similarly to the dimer. The hexasaccharide conjugated to CRM197, a mutant of diphtheria toxin, elicited a robust functional immune response that was not inferior to the polysaccharide conjugate, indicating that it may suffice as a vaccine antigen. This is the first evidence of an X‐ray crystallography‐guided design of a synthetic carbohydrate‐based conjugate vaccine., Deciphering the sugar glycocode: Starting from the X‐ray crystallographic structure of a fragment from Group B Streptococcus type III capsular polysaccharide in complex with a protective mAb complex, a hexasaccharide comprising exclusively the relevant positions involved in interactions was obtained. By structural and immunogenicity studies it was shown that the synthetic hexasaccharide recognized the mAb similarly to the polysaccharide fragment and, conjugated to a carrier protein, suffices as vaccine antigen.

Licensed carbohydrate-based vaccines are obtained by conjugation of native or sized polysaccharides to an appropriate carrier protein. They are part of routine vaccinations in many countries. Advances in the organic and chemo-enzymatic synthesis of carbohydrate antigens combined with novel technologies (e.g., glycoengineering), new conjugation approaches (site-selective protein glycoconjugation), alternative carrier systems and development in glycan structure analysis methods offer new perspectives in the development of carbohydrate-protein conjugate vaccines. This review presents a status of chemistries and analytical methods used in the licensed vaccines as the development of new technologies and new tools that could be used to produce and characterize the future glycoconjugates vaccines.

The aim of the paper is to propose a simulation study to explore the multicollinearity problem in quantile regression, as compared to the classical linear regression. The simulation exploits the concept of a relevant subspace and relevant predictors, considering different degrees of collinearity among the involved predictors. The approach is based on principal components and consists in evaluating the degree of dependence between the predictors on the basis of the eigenvalue structure of their covariance matrix. It is well known that in case of highly intercorrelated predictors the least squares coefficients, although determinate, posses large standard errors, causing precision problems for their estimation. For this reason, results of the simulation study focus on standard errors estimated according to different collinearity levels. A possible solution based on regression on principal components is briefly presented.

Background: Hexachlorocyclohexane (HCH) isomers have been largely employed as pesticides during the 1960's-1970's, and included into the Stockholm Convention persistent organic pollutant list in 2009 with the aim to reach their global elimination. beta-HCH isomer is characterized by a strong lipophilicity, bio-persistence and potential harmful properties for human health. Dispersion of industrial processes and uncontrolled waste storage caused a global environmental beta-HCH contamination. This still represents a public and occupational health concern, not only for past-exposed subjects, but also for the populations that may still be exposed to highly polluted environmental matrices and food. Objective: To provide a critical overview of the existing evidence exploring beta-HCH biomonitoring data and possible health effects in workers involved in the production and use of such compound. Methods: A systematic search and revision of available literature was performed in Pubmed, Scopus, and ISI Web of Science databases. Results: Conclusive evidence concerning the possible dose-response relationship in beta-HCH occupational settings cannot be extrapolated due to the heterogeneity in explored contexts, and the lack of information on environmental conditions and levels of exposure. Nevertheless, biomonitoring data support the need for a deeper understanding of the toxico-kinetic and dynamic profile of the substance, once absorbed into the organism, and possible early alterations in endocrine signaling. Conclusion: The potential toxicity, bioaccumulation and bio-magnification properties of beta-HCH make necessary to plan preventive actions aimed to manage the beta-HCH risk, through the reduction of exposure levels and the definition of health surveillance programs, including biological monitoring investigations, for the general and occupational exposed populations.

In defining destination marketing strategies, a specific role is played by megaevents as critical tool to improve the economic development. In tourism marketing literature, researchers have analysed the holistic perspective of tourist behaviour to understand the factors that influence the level of satisfaction and the intentional behaviours. Accordingly, the paper aimed at analysing relationships among destination image, event satisfaction and tourist behavioural intentions in sport mega-event. Six research hypotheses have been formulated and empirically tested by using structural equation models (Partial Least Squares – PLS approach) on survey data from 304 international tourists who attended the America’s Cup World Series in Naples. The findings put in evidence the relevant role of the mega-event to create value for tourist in destination management.

Purpose The purpose of this paper is to investigate the impact of consumer-brand engagement and brand experience on behavioural intentions (i.e. intent to re-purchase, willingness to accept brand extension, willingness to pay a premium price) in relation to food brands. Design/methodology/approach The authors propose a conceptual model comprising five latent variables and 26 manifest variables. A questionnaire with questions relating to pasta and coffee was given to an Italian consumer sample (n=400). The model was tested using structural equation modelling of the resulting data to examine the research hypotheses. Findings The empirical study confirms the predictive role of the two selected drivers of brand value. Both consumer-brand engagement and brand experience influenced behavioural intentions, but these brand constructs had different roles in the two product categories examined in the study, pasta and coffee. Research limitations/implications This study does have limitations. First, the generalisability of the findings should be considered. The study refers to only two product categories in a specific country. It would be interesting to investigate the issue of food brand engagement and brand experience in different countries, and to compare the results. Furthermore, it would be valuable to investigate the impact of brand engagement and brand experience in other product categories. Practical implications The results have an important implication for marketing managers: they should develop long-term and strong brand relationships. Such consumer engagement and/or experiential actions can be key competitive advantages for food companies. Originality/value The study provides empirical support for the effect of consumer-brand engagement and brand experience on consumers’ behavioural intentions in the food industry.

Transglutaminases are a family of Ca2+-dependent enzymes which catalyze post-translational modifications of proteins. The main activity of these enzymes is the cross-linking of glutaminyl residues of a protein/peptide substrate to lysyl residues of a protein/peptide co-substrate. In addition to lysyl residues, other second nucleophilic co-substrates may include monoamines or polyamines (to form mono-or bi-substituted/crosslinked adducts) or -OH groups (to form ester linkages). In absence of co-substrates, the nucleophile may be water, resulting in the net deamidation of the glutaminyl residue. Transglutaminase activity has been suggested to be involved in molecular mechanisms responsible for both physiological and pathological processes. In particular, transglutaminase activity has been shown to be responsible for human autoimmune diseases, and Celiac Disease is just one of them. Interestingly, neurodegenerative diseases, such as Alzheimer’s disease, Parkinson’s disease, supranuclear palsy, Huntington’s disease and other polyglutamine diseases, are characterized in part by aberrant cerebral transglutaminase activity and by increased cross-linked proteins in affected brains. Here we describe the possible molecular mechanisms by which these enzymes could be responsible for such diseases and the possible use of transglutaminase inhibitors for patients with diseases characterized by aberrant transglutaminase activity.