Environmental and economic assessment for the optimal configuration of a sustainable solid waste collection system: a ‘kerbside’ case study

The article presents a case study concerning the improvement of the ‘kerbside’ waste collection system, now increasingly implemented in many Italian municipalities, as an alternative to traditional bring collection, with the aim of increasing the quality of waste collection and the collection rate, in order to reduce the final impact on the environment. A planning model for an integrated waste management system based on kerbside collection is presented. A heuristic procedure is also applied in order to obtain some admissible solutions of the real problem in reasonable computational time. The economic and environmental impacts are considered as significant elements for the evaluation and validation of the obtained solutions. Five alternative configurations of kerbside system, diverging in number of sub-area, synchrony of vehicles and directionality of the arcs, are compared in an economic point of view. Finally, Life-Cycle Assessment is used as a tool to compare the overall potential environmental impacts of the alternative of kerbside collection systems and also to compare the kerbside system with the traditional bring one. The different scenarios of kerbside system are comparable in terms of damage on the impact categories, while the bring system is the worst one, in terms of damage on human health, in the consumption of resources and also for the total damage score.     

Estimating bird species richness from capture and count data

We used capture-recapture methods to estimate bird species richness from mist-net and point-count data from a study area in Campeche, Mexico. We estimated species richness separately for each survey technique for two habitats, forest and pasture, in six sampling periods. We then estimated richness based on species' detections by either technique, and estimated the proportion of species detected by each technique that are not part of the population sampled by the other technique. No consistent differences existed between richness estimates from count data and from capture data in the two habitats. In some sampling periods, over 50% of the richness estimate from one survey technique may be species that are not sampled by the other technique, suggesting that one technique may not be adequate to estimate total species richness and that comparing estimates from areas sampled by different techniques may not be valid.     

Does Religious Diversity in Health Team Composition Affect Efficiency? Evidence from Dubai

Team cultural diversity, the degree to which working team members differ in culture‐related factors, may affect healthcare teams’ outcomes. This paper focuses on one particular source of cultural diversity, namely religion, and examines its relation to the production efficiency of hospital wards. Building on the categorization‐elaboration model of organizational diversity, the authors test an empirical model positing that team religious diversity has non‐linear effects on efficiency, and considering the role of moderating variables of the relation diversity–efficiency. Empirically, the authors adopt a two‐step approach, whereby the first step applies data envelopment analysis to estimate efficiency scores for each team, and the second investigates the effect of diversity and of moderating variables. The model is tested on a sample of hospital wards from three large hospitals in Dubai. The results suggest an inverse U‐shaped relation between religious diversity and the wards’ efficiency. Evidence is provided that the relation is moderated by task complexity, task conflict, team leader tenure and diversity in nationality. This study advances research on the management of hospital team diversity by emphasizing the complexity of diversity effects and the importance of contextual factors.     

De gustibus non est disputandum? A new approach to the estimation of equivalence scales

We argue that when the household composition changes, consumption patterns vary not only because of the cost effect that equivalence scales try to measure, but also because of a “taste” or “style” effect. This effect can be identified and measured, under a few assumptions, with the use of a new methodology, calledDM ² (Decomposition Model of the effects of Demographic Metamorphosis), that can be viewed as a generalisation of Ray's (1983) price-scaling approach to the construction of equivalent scales. An empirical application to data drawn from the Istat 1995 Italian Household Budget Survey suggests that the proposed method improves our understanding of households' consumption patterns and the reliability of the equivalence scales that we derive. We gratefully acknowledge helpful comments from Giorgio Calzolari, Franco Polverini, Ugo Trivellato and an anonymous referee, but retain full responsibility for all errors, and for the processing of Istat (Italian Institute of Statistics) microdata on Household Budgets. Financial support for this research was provided by the italian MURST (Research project on “Equivalence scales” directed by Prof. Guido Ferrari, University of Firenze, Ref. No. 9913105354; and Research project on “Low fertility in Italy: between economic constraints and value changes”, directed by Prof. Massimo Livi Bacci, University of Firenze, Ref. No. MM13107238). Preliminary findings on this research topic have been presented in a few seminars and conferences: cf., e.g., De Santis and Maltagliati (2000 and 2001).     

Expectations About Future Economic Prospects and Satisfaction with Democracy: Evidence from European Countries during the COVID-19 Crisis

Social Indicators Research - Recent studies highlight that economic expectations are a crucial determinant of citizens’ satisfaction with democracy (SWD). This article relies on a...     

Reduction of the Three-Partition Problem

The three-partition problem is one of the most famous strongly NP-complete combinatorial problems. We introduce properties which, in many cases, can allow either a quick solution of an instance or a reduction of its size. The average effectiveness of the properties proposed is tested through computational experiments.     

On zero-sum $$\mathbb {Z}_{2j}^k$$-magic graphs

Let \(G = (V,E)\) be a finite graph and let \((\mathbb {A},+)\) be an abelian group with identity 0. Then G is \(\mathbb {A}\)-magic if and only if there exists a function \(\phi \) from E into \(\mathbb {A} - \{0\}\) such that for some \(c \in \mathbb {A}, \sum _{e \in E(v)} \phi (e) = c\) for every \(v \in V\), where E(v) is the set of edges incident to v. Additionally, G is zero-sum \(\mathbb {A}\)-magic if and only if \(\phi \) exists such that \(c = 0\). We consider zero-sum \(\mathbb {A}\)-magic labelings of graphs, with particular attention given to \(\mathbb {A} = \mathbb {Z}_{2j}^k\). For \(j \ge 1\), let \(\zeta _{2j}(G)\) be the smallest positive integer c such that G is zero-sum \(\mathbb {Z}_{2j}^c\)-magic if c exists; infinity otherwise. We establish upper bounds on \(\zeta _{2j}(G)\) when \(\zeta _{2j}(G)\) is finite, and show that \(\zeta _{2j}(G)\) is finite for all r-regular \(G, r \ge 2\). Appealing to classical results on the factors of cubic graphs, we prove that \(\zeta _4(G) \le 2\) for a cubic graph G, with equality if and only if G has no 1-factor. We discuss the problem of classifying cubic graphs according to the collection of finite abelian groups for which they are zero-sum group-magic.     

Association between dietary phytoestrogens intakes and prostate cancer risk in Sicily

Objective: In this study we aimed to investigate the association between dietary phytoestrogen consumption and prostate cancer in a sample of southern Italian individuals.

Methods: A population-based case-control study on the association between prostate cancer and dietary factors was conducted from January 2015 to December 2016 in a single institution of the municipality of Catania, southern Italy (Registration number: 41/2015). A total of 118 histopathological-verified prostate cancer (PCa) cases and a total of 222 controls were collected. Dietary data was collected by using two food frequency questionnaires.

Results: Patients with PCa consumed significantly higher levels of phytoestrogens. Multivariate logistic regression showed that lignans (Q[quartile]4 vs. Q1, OR [odds ratio]?=?4.72; p?p?p?p?p?p?p?Conclusion: We found of an inverse association between dietary isoflavone intake and PCa, while a positive association was found with lignans intake.     

Reference database of hematological parameters for growing and aging rats

The normal hematological values in various phases of the rat life provide a valuable guide to researchers and could be useful for experimental works. However, database information available on the literature are incomplete. Aim: This study aimed to present normal hematological parameters of young and aged rats.

Methods: Male and female rats were distributed into seven experimental groups with 1, 2, 3, 6, 12, 18, and 24 months of age. Blood samples taken from the tails were analyzed. Normal hematological values were determined for each age group.

Results: Rats showed a progressive weight gain with advancing age, predominantly after 3 months of life. With advancing age, differences were found on hematological parameters: some of them showed a progressive rise with age and others did not. Hemoglobin levels and hematocrit did not change while the number of circulating red blood cells suffered slight increase.

Conclusion: The present study determined the normal values for absolute and relative hematological parameters in Wistar rats from 2 to 24 months for male and female rats. The results can be used in studies of effects of aging, feeding, and medications on growing and aging rats.