High order PLS path modeling to evaluate well-being merging traditional and big data: A longitudinal study

[EN] We propose using high order partial least squares path modeling (PLS-PM) todefine a synthetic Italian well-being index merging traditional data,represented by the Quality of Life index proposed by “Il Sole 24 Ore”, andinformation provided by big data, represented by a Subjective Well-beingIndex (SWBI) performed extracting moods by Twitter. High order constructs,which allow to define a more abstract higher-level dimension and its moreconcrete lower-order sub-dimensions, have gained wide attention inapplications of PLS-PM, and many contributions in literature proposed theiruse to build composite indicators. The aim of the paper is to underline somecritical issues in the use of these models and to suggest the implementation ofa new spurious repeated indicator approach. Furthermore, following somerecommendations proposed on the use of PLS-PM in longitudinal studies, wecompare the situation in 2016 and 2017.De Battisti, F.; Siletti, E. (2020). High order PLS path modeling to evaluate well-being merging traditional and big data: A longitudinal study. Editorial Universitat Politècnica de València. 95-102. https://doi.org/10.4995/CARMA2020.2020.11599OCS9510

A study on the impact of AL-FEC techniques on TV over IP Quality of Experience

Abstract In this contribution, an evaluation of the effectiveness of Application Layer-Forward Error Correction (AL-FEC) scheme in video communications over unreliable channels is presented. In literature, several AL-FEC techniques for reducing the effect of noisy transmission on multimedia communication have been adopted. Recently, their use has been proposed for inclusion in TV over IP broadcasting international standards. The objective of the analysis performed in this paper is to verify the effectiveness of AL-FEC techniques in terms of perceived Quality of Service (QoS) and more in general of Quality of Experience (QoE), and to evaluate the trade-off between AL-FEC redundancy and video quality degradation for a given packet loss ratio. To this goal, several channel error models are investigated (random i.i.d. losses, burst losses, and network congestions) on test sequences encoded at 2 and 4 Mbps. The perceived quality is evaluated by means of three quality metrics: the full-reference objective quality metric NTIA-VQM combined with the ITU-T Rec. G.1070, the full-reference DMOS-KPN metric, and the pixel-wise error comparison performed by using the PSNR distortion measure. A post-processing synchronization between the original and the reconstructed stream has also been designed for improving the fidelity of the performed quality measures. The experimental results show the effectiveness and the limits of the Application Layer protection schemes

A study on the impact of AL-FEC techniques on TV over IP Quality of Experience

Abstract In this contribution, an evaluation of the effectiveness of Application Layer-Forward Error Correction (AL-FEC) scheme in video communications over unreliable channels is presented. In literature, several AL-FEC techniques for reducing the effect of noisy transmission on multimedia communication have been adopted. Recently, their use has been proposed for inclusion in TV over IP broadcasting international standards. The objective of the analysis performed in this paper is to verify the effectiveness of AL-FEC techniques in terms of perceived Quality of Service (QoS) and more in general of Quality of Experience (QoE), and to evaluate the trade-off between AL-FEC redundancy and video quality degradation for a given packet loss ratio. To this goal, several channel error models are investigated (random i.i.d. losses, burst losses, and network congestions) on test sequences encoded at 2 and 4 Mbps. The perceived quality is evaluated by means of three quality metrics: the full-reference objective quality metric NTIA-VQM combined with the ITU-T Rec. G.1070, the full-reference DMOS-KPN metric, and the pixel-wise error comparison performed by using the PSNR distortion measure. A post-processing synchronization between the original and the reconstructed stream has also been designed for improving the fidelity of the performed quality measures. The experimental results show the effectiveness and the limits of the Application Layer protection schemes

Empirical insights on the nature of synergies among HRM policies - an analysis of an ethics-oriented HRM system

In the last years, several HRM scholars have theoretically support the idea that the policies bundled in an HRM system present synergistic effects. Surprisingly, empirical studies about those synergistic effects are scarce, and their results unstable. As a result, some critical voices in the HR field are questioning the idea of synergies among HR policies, and calling for more research which does not take them for granted. Addressing this gap, this study tests the existence and nature of synergies in HRM systems targeted at improving the employees' perception of benevolent and principled ethical climates. Results from a probabilistic sample of 6000 employees from 6 European countries highlight that synergies occur both for benevolent and principled ethical climates, even if the specific components of the HRM system presenting synergistic effects are different in the two cases. Implications of the findings for HRM practice are presented and discussed

First evidence of root morphological and architectural variations in young Posidonia oceanica plants colonizing different substrate typologies

Root morphology and root system architecture of young Posidonia oceanica plants established on two contrasting substrate types, sand and rock, were examined to provide insights into the strategy of adaptation of seagrasses to their environment. After germination, seedlings were planted on sandy patches and on rock within the same area, and survived plants were collected five years later for measurements of the size of the entire root complex and analysis of individual morphological and architectural root traits. Collected plants exhibited up to nine highly intermingled root systems and approx. 2.5 m of total root length. Maximum horizontal extension, total biomass and total length of roots were not significantly affected by substrate. However, on sand roots grew vertically reaching up to 13 cm, while on rock they extended more horizontally and did not penetrate deeper than 5e7 cm leading to the formation of a shallow, densely packed root complex. On rock, the number and the length of second order laterals on an individual root system were reduced and the topological index higher than on sand (0.8 vs. 0.7) reflecting a more simple (herringbone) branching pattern. Again, root diameter was greater than on sand. The results suggest that P. oceanica can adjust root traits early during plant development according to substrate typology to maximize anchorage and substrate exploration efficiency. This plasticity enables the species to establish and persist also on rocky bottoms which generally prevent establishment of the majority of seagrasses

Bronchopulmonary Nematodes in Alpine Ibex: Shedding of First Stage Larvae Analyzed at the Individual Host Level

Pneumonia is the most frequent cause of death for Alpine ibex (Capra ibex) in Gran Paradiso National Park, (Italy). The etiology of this form of pneumonia is currently unknown and the identification of the primary etiological agent remains difficult due to biological and logistic constraints. Uncovering individual differences in Protostrongylid prevalence and intensity is important to further investigate the epidemiology of respiratory diseases and their relationship to heterozygosity and inbreeding in a once almost extinct population like C. ibex. In a group of 21 individually recognizable adult male we monitored monthly prevalence and intensity of Protostrongylid first-stage larvae using Baerman's technique from June to September 2019. First-stage larvae of 5 genera were detected. Muellerius (P = 100%, CI95% = 84–100) and Protostrongylus (P = 86%, CI95%:71–100) were two dominant genera according to Bush's importance index. Neostrongylus (P = 38%,CI95%: 17–59), Cystocaulus (P = 33%,CI95% = 13–53) were classified as co-dominant genera while Dictyocaulus filaria (P = 0.05%, CI95% = 0.04–0.13) was detected, for the first time in Alpine ibex, in one subject. Protostrongylidae larval excretion varied significantly over time, with minimum L1 excretion in July. Individual median larval intensity ranged from 4.4 lpg to 82.2 lpg with Poulin's discrepancy index showing highly aggregated distribution patterns for Muellerius spp. (D = 0.283, CI95% = 0.760–0.895) and Protostrongylus spp. (D = 0.635, CI95% = 0.580–0.705). Presented data provide the necessary base point to further investigate how lungworm infection account for the different rates of progression of pneumonia in C. ibex. Individual aggregation of larval intensity must be further evaluated to determine whether these differences mirror different levels of parasitic infection related to individual differences in immune response, hormonal-states or genetic fitness