Lorenzo Market between Diversity and Mutation

The aim of this paper is to investigate the relationship between the diversity of groups of workers and the local division of labour in the San Lorenzo Market, Florence, Italy. This empirical research may help distinguish the demographic, migratory and occupational patterns of the workers in accordance with their national origin. It shows that geographical origin is the key to the differences, specialisations and oppositions between the Florentines and the various groups of migrants on the one hand, and between these immigrant groups on the other hand. It shows too the mutation made by the conflict between global dynamics and a local labour market.San Lorenzo Market, Immigrant workers, Diversity, Local division of labour, Migratory trajectories

F. CARCHEDI, V. TOLA (a cura di), All'aperto e al chiuso. Prostituzione e tratta : i nuovi dati del fenomeno, i servizi sociali, le normative di riferimento, Roma, Ediesse, 2008, pp 438 A. BERNARDOTTI, F. CARCHEDI, B. FERONE (a cura di), Schiavitù emergenti. La tratta e lo sfruttamento delle donne nigeriane sul litorale domito, Roma, Ediesse, 2005, pp 224 (fiche de lecture)

fiche de lecture version longuePrésentation - en version longue- de deux ouvrages sur la prostitution en Itali

Esplorare un mercato cosmopolita

Cet article rapporte les résultats d'une enquête réalisée en 1999 sur un espace de travail particulier : le Marché San Lorenzo dans le centre-ville touristique de Florence en Italie. Il soulève le problème des rapports socio-professionnels entre d'un côté les travailleurs migrants et les employeurs florentins, et d'un autre côté entre les divers groupes communautaires selon leur temporalité migratoire et leur insertion dans le marché du travail local. Est mise en évidence la substitution du patronat florentin/italien par les Iraniens, et également la diversité et la fluidité des employés migrants.Il contributo qui presentato si fonda su un inchiesta realizzata nel 1999 su uno spazio di lavoro particolare : il Mercato San Lorenzo, nel centro-città di Firenze, Italia. Pone il problema dei rapporti socio-professionali fra da un lato i lavoratori migranti e i padroni fiorentini, e da un altro lato fra i diversi gruppi comunitari a secondo dalla propria temporalità migratoria e inserimento nel mercato locale del lavoro. Evidenzia la sostituzione dei padroni fiorentini/italiani dai Persiani e la fluidità dei comessi migranti

Logiques migratoires et rapports de travail, les travailleurs étrangers dans un espace de travail localisé : le marché touristique de San Lorenzo à Florence, Italie

Cet article rapporte les résultats d'une enquête réalisée en 1999 sur un espace de travail particulier : le Marché San Lorenzo dans le centre-ville touristique de Florence en Italie. Il soulève le problème des rapports socio-professionnels entre d'un côté les travailleurs migrants et les employeurs florentins, et d'un autre côté entre les divers groupes communautaires selon leur temporalité migratoire et leur insertion dans le marché du travail local. Est mise en évidence la substitution du patronat florentin/italien par les Iraniens, et également la diversité et la fluidité des employés migrants.Il contributo qui presentato si fonda su un inchiesta realizzata nel 1999 su uno spazio di lavoro particolare : il Mercato San Lorenzo, nel centro-città turistico di Firenze, Italia. Pone il problema dei rapporti socio-professionali fra da un lato i lavoratori migranti e i padroni fiorentini, e da un altro lato fra i diversi gruppi comunitari a seconda della propria temporalità migratoria e inserimento nel mercato locale del lavoro. Evidenzia la sostituzione dei padroni fiorentini/italiani dai Persiani, e anche la diversità e la fluidità dei comessi migranti

Differences in the Critical Thermal Maximum Between Two Size Classes of Stenonema femoratum (Ephemeroptera: Heptageniidae)

Temperature is an important variable affecting the behavior and survival of aquatic organisms; however, little is known about the effects of size and corresponding developmental differences on aquatic insect temperature tolerance. We tested the critical thermal maximum (CTM) of large (head capsule width mean = 3.5 mm) and small (1.9 mm) specimens of Stenonema femoratum (Say) by raising the experimental temperature by 0.1, 0.3, and 0.5ºC per minute during laboratory CTM trials. Size class and temperature increase rate combinations were randomized, and each combination was tested over four trials, for a total of 24 trials of four specimens each. Two-way Analysis of Variance determined CTM was significantly higher for small specimens (35.2°C) compared to large specimens (33.0°C) regardless of temperature increase rate. There was no significant difference in CTM based on temperature increase rate, or interactions between size class and temperature increase rate. This result demonstrates that the highest thermal tolerance of a species is not necessarily it its largest specimens, and that determining a single CTM for a species based on multiple size classes would likely lead to erroneous results

Influence of previous participation in physical activity on its perceptions among tertiary institution students

Physical inactivity is one of the leading causes of the major non-communicable diseases, which contribute substantially to the global burden of diseases, death and disability. The burden of mortality, morbidity and disability attributable to non-communicable diseases is currently greatest and is continually growing in the developing countries. Most declines in physical activity (PA) occur during the transition period when a person goes from high school to College or University. The objectives of this study were to identify perceived benefits of and barriers to PA and determine whether previous participation in PA does have an influence on these perceptions. A cross- sectional and descriptive study with quantitative design was conducted. Five hundred (500) tertiary institution students were randomly sampled from purposively selected departments and classes at each of the five government educational tertiary institutions in Rwanda. A pre-coded self-administered questionnaire with a small number of open-ended questions was administered to the students. A response rate of 425 (85%) was obtained. Descriptive and inferential statistics were used to analyse the data, by means of SAS version 8 software. Frequencies and percentages for mean score values with standard deviations for each perception variable were descriptively obtained. False Discovery Rate (FDR) at 5% for multiple test adjustment and Spearman’s correlation (r) tests were used to identify the significant influence of previous participation on perceptions. More than 70% students were not participating in PA at tertiary level. Psychological benefits of PA were some of the most important perceived benefits cited by the students. Most of the important barriers cited concerned equipment and time constraints to exercising. Associations were found between previous participation and the current perceptions of PA. The findings of this study demonstrate that previous participation can influence perceptions of PA among the students. Physical activity promotion programmes should consider the role of these factors which should be emphasised from childhood

Taming the rugged energy landscape: Techniques for the production, reordering, and stabilization of selected cluster inherent structures

We report our studies of the potential energy surface (PES) of selected binary Lennard-Jones clusters. The effect of adding selected impurity atoms to a homogeneous cluster is explored. Inherent structures and transition states are found by combination of conjugate-gradient and eigenvector-following methods while the topography of the PES is mapped with the help of a disconnectivity analysis. We show that we can controllably induce new structures as well as reorder and stabilize existing structures that are characteristic of higher-lying minima.Comment: 9 pages, 9 figures, accepted for publication in J. Chem. Phy

Stereoscopic high-speed imaging for 3D tracking of coughed saliva droplets in the context of COVID-19 spreading

Droplets generated by talking and coughing play a major role in the spreading of COVID-19. There is thus a need for accurate measurements of the physical properties of exhaled droplets, including their number, speed and direction.Several challenges are associated with imaging coughed droplets such as high droplet speed near the mouth where both short exposure time to freeze droplet motion and kHz recording rate to resolve their displacement is required. In addition, as a highly non-symmetrical spray system is formed from a cough, three-dimensional visualization is necessary to faithfully capture coughing events. In this work, a 3D, high-speed imaging technique is presented that facilitates such challenging measurements. A laser beam with a probe volume 15 mm thick - 120 mm high is formed and illuminates droplets exiting the mouth imaged using two high-speed cameras. Data has been recorded for four different male subjects where 3D droplet speed and direction has been extracted for 10 coughs each. The maximum speed for a single cough has been estimated to vary between 11 and 45 m/s and the average droplet speed has been found to be in the range 6.5 - 8.7 m/s. These results will be used as input parameters to improve simulation models of droplet transport in the context of virus spreading

Reducing Quasi-Ergodic Behavior in Monte Carlo Simulations by J-Walking: Applications to Atomic Clusters

A method is introduced that is easy to implement and greatly reduces the systematic error resulting from quasi-ergodicity, or incomplete sampling of configuration space, in Monte Carlo simulations of systems containing large potential energy barriers. The method makes possible the jumping over these barriers by couplingn the usual Metropolis sampling to the Boltzmann distribution generated by another random walker at a higher temperature. the basic techniques are illustrated on some simple classical systems, beginning for heuristic purposes with a simple one-dimensional double well potential based on a quartic polynomial. the method\u27s suitability for typical multidimensional Monte Carlo systems is demonstrated by extending the double well potential to several dimensions, and then by applying the method to a multiparticle cluster system consisting of argon atoms bound by pairwise Lennard-Jones potentials. Remarkable improvements are demonstrated in the convergence rate for the cluster configuration energy, and especially for the heat capacity, at temperatures near the cluster melting transition region. Moreover, these improvements can be obtained even in the worst-case scenario where clusters are initialized from random configurations