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ABSTRACTMerritton, Ontario, was a 19th-century boom town with many and various mills. This industrial corridor was largely the product of developments in technology, especially in transportation and communication. The Welland canals provided water power for industries and provided links to the wider world. Railways supplemented the canals. War needs and tariff policies helped the town's growth. Local entrepreneurs and town taxation policies played roles. Nevertheless, scientific discoveries applied to production were significant factors. Technological factors were equally important in contributing to the town's decline. Merritton's rise and fall shows how technology, both at the global and local levels, can create, nurture and abandon small human communities.

Numerous procedure for the isolation of aquatic humic substances are described in literature. The first part of this study presents the extraction of fulvic and humic acids from eleven French surface waters, using XAD 8 macroreticular resin as developed by TRURMAN and MALCOLM (1981). The results are discussed in terms of extraction yield and fulvic acid/humic acid mass ratio.The second part of the paper presents some structural parameters of the extracted fulvic acids such as elemental analysis, UV-absorbance, carboxyle-function content and in some cases of fulvic acids, infrared spectrum and apparent molecular weight investigated by ultra filtration.The third part of the work concerns the study of fulvic acids chlorination. Firstly, the gas chromatography - mass spectrometry analysis of one chlorinated fulvic acid allowed us to identify some chlorination by-products and especially chloroform, dichloro-acetic and trichloroacetic acids and some other chlorinated aliphatic acids. Secondly, the chlorine reactivity potentials of each fulvic acids were determined and results are discussed in terms of chlorine consumption, chloroform and total organohalides formation potentials. Some relationships are established between the chlorine reactivity potentials and UV-absorbance of the extracted fulvic acids.

Keywords: Substances humiques aquatiques, acides fulviques, extraction, caractérisation, chloration, produits organo-chlorés, Aquatic humic substances, fulvic acids, isolation, characterisation, chlorination, organohalides

The concept of partial membership of a hydrometric station in a hydrologic region is modeled using fuzzy sets theory. Hydrometric stations are represented in spaces of hydrologic (coefficient of variation: CV, coefficient of skewness: CS, and their counterparts based on L- moments: L-CV and L-CS) and/or physiographic attributes (surface of watershed: S, specific flow: Qs=Qmoyen/S, and a shape index: Ic). Two fuzzy clustering methods are considered.First a clustering method by coherence (Iphigénie) is considered. It is based on the principle of transitivity: if two pairs of stations (A,B) and (B,C) are known to be "close" to one another, then it is incoherent to state that A is "far" from C. Using a Euclidean distance, all pairs of stations are sorted from the closest pairs to the farthest. Then, the pairs of stations starting and ending this list are removed and classified respectively as "close" and "far". The process is then continued until an incoherence is detected. Clusters of stations are then determined from the graph of "close" stations. A disadvantage of Iphigénie is that crisp (non fuzzy) membership functions are obtained.A second method of clustering is considered (ISODATA), which consists of minimizing fuzziness of clusters as measured by an objective function, and which can assign any degree of membership between 0 to 1 to a station to reflect its partial membership in a hydrologic region. It is a generalization of the classical method of mobile centers, in which crisp clusters minimizing entropy are obtained. When using Iphigénie, the number of clusters is determined automatically by the method, but for ISODATA it must be determined beforehand.An application of both methods of clustering to the Tunisian hydrometric network (which consists of 39 stations, see Figure 1) is considered, with the objective of obtaining regional estimates of the flood frequency curves. Four planes are considered: P1: (Qs,CV), P2: (CS,CV), P3: (L-CS,L-CV), and P4: (S,Ic), based on a correlation study of the available variables (Table 1).Figures 2, 3a, 4 and 5 show the clusters obtained using Iphigénie for planes P1 through P4. Estimates of skewness (CS) being quite biased and variable for small sample sizes, it was decided to determine the influence of sample size in the clusters obtained for P2. Figure 3b shows the clusters obtained when the network is restricted to the 20 stations of the network for which at least 20 observations of maximum annual flood are available. Fewer clusters are obtained than in Figure 3, but it can be observed that the structure is the same: additional clusters appearing in Figure 3 may be obtained by breaking up certain large clusters of Figure 3b. In Figure 3c, the sample size of each of the 39 stations of the network is plotted in the plane (CS,CV), to see if extreme estimated values of CS and CV were caused by small samples. This does not seem to be the case, since many of the most extreme points correspond to long series.ISODATA was also applied to the network. Based on entropy criteria (Table 2, Figures 6a and 6b), the number of clusters for ISODATA was set to 4. It turns out that the groups obtained using ISODATA are not very fuzzy. The fuzzy groups determined by ISODATA are generally conditioned by only one variable, as shown by Figures 7a-7d, which respectively show the fuzzy clusters obtained for planes P1-P4. Only lines of iso-membership of level 0.9 were plotted to facilitate the analysis. For hydrologic spaces (P2 and P3), it is skewness (CS and L-CS) and for physiographic spaces (P1 and P4) it is surface (Qs and S). Regionalization of the 100-year return period flood is performed based on the homogeneous groups obtained (using an index-flood method), and compared to the well-known region of influence (ROI) approach, both under the hypothesis of a 2-parameter Gamma distribution and a 3-parameter Pareto distribution. For the ROI approach, the threshold corresponding to the size of the ROI of a station is taken to be the distance at which an incoherence first appeared when applying Iphigénie. Correlation of the regional estimate with a local estimation for space P1 is 0.91 for Iphigénie and 0.85 both for ISODATA and the ROI approach. Relative bias of regional estimates of the 100-year flood based on P1 is plotted on Figures 9 (Gamma distribution) and Figure 10 (Pareto distribution). The three methods considered give similar results for a Gamma distribution, but Iphigénie estimates are less biased when a Pareto distribution is used. Thus Iphigénie appears superior, in this case, to ISODATA and ROI. Values of bias and standard error for all four planes are given for Iphigénie in Table 3.Application of an index-flood regionalization approach at ungauged sites requires the estimation of mean flow (also called the flood index) from physiographic attributes. A regression study shows that the best explanatory variables are watershed surface S, the shape index Ic and the average slope of the river. In Figure 8, the observed flood index is plotted against the flood index obtained by regression. The correlation coefficient is 0.93.Iphigénie and ISODATA could also be used in conjunction with other regionalization methods. For example, when using the ROI approach, it is necessary to, quite arbitrarily, determine the ROI threshold. It has been shown that this is a byproduct of the use of Iphigénie. ISODATA is most useful for pattern identification when the data is very fuzzy, unlike the example considered in this paper. But even in the case of the Tunisian network, its application gives indications as to which variables (skewness and surface) are most useful for clustering.

Keywords: Hydrologie, régionalisation, crues, flou, gamma, pareto, iphigénie, ISODATA, Hydrology, regionalization, 100-year flood, fuzzy sets, gamma, pareto, Iphigénie, ISODATA

The drought observed for more than twenty years in the sahelian countries has also affected those located more to the South with more humid climates (SUTCLIFFE and KNOTT, 1987; NICHOLSON et al, 1988; MAHE and OLIVRY, 1991; OLIVRY et al, 1993 PATUREL et al, 1995). The decrease in rainfall and consequently that in runoff might penalise development projects linked with water supply. The ICCARE programme led by ORSTOM aimed at identifying and measuring the consequences of this climatic variability in the non-sahelian parts of the West and Central African region as a whole. The study was based on rainfall data from more than two hundred stations, break detection methods in the time series as well as cartographic tools were used. This study allowed to highlight the manifestations of the climatic variability observed for nearly 25 years in West and Central Africa. Whereas it had been thought for a long time that the rainfall deficit was restricted to the sahelian region, this study showed that the forest covered regions were also affected and generally speaking the so-called 'humid Africa'. The decrease in rainfall entails that in runoff and thus a change in water resources availability which is the cornerstone of a fairly great number of development projects. Hydrological regimes variability and possible modifications of rainfall-runoff relationship are to be the next stages of the ICCARE programme, partial results were already published (SERVAT et al, 1997). A simple study of the time series showed straightforward fluctuations of the rainfall patterns (figures 2 and 3), which happened during the late sixties or the early seventies over the whole region. The mapping of the time series analysis depicts a clear general trend towards a shift of the isohyets to the south-south-west from the 1950's to the 1980's. This shift reflects a sharp drop in the annual rainfall over the whole of the non-sahelian west and central Africa. Generally speaking it appears that the zones with extreme rainfall patterns underwent the most important modifications, namely : the wettest ones from Guinea to Ivory Coast and the driest ones, bordering the sahelian region to the North of the studied area. Elsewhere changes are less drastic (SERVAT et al, 1996). The different statistical procedures applied to the series of annual rainfall showed breaks taking place during the late 1960's or the early 1970's (figure 4), which was in keeping with what had been observed in the sahelian region. Rainfall deficits were in the order of 20% and they could reach values higher than 25% (table 1), in particular along the Atlantic Coast or in the North, which upholds the fact that 'humid Africa' was also severely affected by the rainfall variability. Other variables which allow a more qualitative characterisation of the phenomenon were also studied (table 2) (figures 5 and 6) ( PATUREL et al, 1997, SERVAT et al, 1997). They brought complementary information about the ways the rainfall variability expresses itself. The pattern of the rainy season was slightly different from what it had been before the 1970's, its length was generally shorter either because it started later than before or because it ended earlier. Likewise, the rainfall distribution was modified, which resulted in a more 'homogeneous' pattern for the zone with only one rainy season and in a sensible change in the ratio of the rainfall heights of the two rainy seasons. Some of the regions of the so-called 'wooded' savannah saw a modification of their climate with a shift from a 'guinean' climate toward a 'sudanese' one. In west Africa some regions saw also a decrease of the amount of precipitation occurring outside the rainy season, which led to a strengthening of the dry season and contributed, if need be, to the perception of the phenomenon by local populations. The decrease in the number of rainy days, where it was possible to study it, was in line with the rainfall deficit. A complementary statistical approach was carried out, it consists of a spatio-temporal study using a multidimensional exploratory analysis (KHODJA et al, 1998). This led to using a multivariate test for detecting a shift in the mean value. This approach confirmed the results obtained with univariate analyses whether it is for the time location of the break (late 1960's, early 1970's) or whether for the heterogeneous character of the phenomenon both from a spatial or temporal point of view. A major characteristic of this persisting rainfall deficit seems to be the existence of two axes of heterogeneity along the north-south and east-west directions (table 3) (figure 7). The survey of the rainfall time series from the origin allowed to place the drought in a historical perspective. So, it appears that, since the beginning of the century, the region underwent a succession of dry and wet periods, although it is difficult to speak of cycles. The phenomenon observed during the late 60's and the early 70's appears, however, as the most significant from a statistical point of view. Besides, the still lasting period of deficit has displayed a length and an intensity quite remarkable, in particular in the north and west sectors of the studied zone where the phenomenon presents an even more exceptional character (figures 8,9,10 and 11). Even though what brought about this diminution in rainfall remains, until now, unexplained, certain human activities undoubtedly contributed to the aggravation of the phenomenon. Although deforestation cannot be held entirely responsible for the drought, the fact remains that overlogging helped to increase the rainfall deficit in numerous regions along the Atlantic coast and the Guinean gulf. Of course, this rainfall deficit has important consequences on the availability of water resources in those regions. Agriculture, the filling of dams and therefore the hydroelectric production, to mention only a few domains, are strongly penalised by this decrease in resources. If a real shortage is not to be feared in those regions where the quantities of precipitation remain high in absolute terms, the effects of that variability can still prove to be disastrous, as they modify the elements of a balance that is already threatened by other factors (anthropic pressure and deforestation, for example). The ICCARE programme, which goes on with the study of the modifications of the river hydrological regimes, will give answers as to the effect of the rainfall deficit upon water resources availability.

Keywords: Afrique de l'Ouest et Centrale, Pluviométrie, Variabilité climatique, Sécheresse, Séries chronologiques, Détection de ruptures, Western and Central Africa, Rainfall, Climate variability, Drought, Time series, Break detection

This paper is the French translation of Ayelet Shachar's introduction, «The Puzzle of Birthright Citizenship», digitally reproduced by permission of the publisher from The Birthright Lottery : Citizenship and Global Inequality, Cambridge, Mass.: Harvard University Press, pp.1-18. © 2009 by the President and Fellows of Harvard College. Translation by Martin Provencher.

The aim of this research is to understand, within the institutional field of French retailing, the carbon strategies that are implemented by integrated retailers such as Auchan, Casino and Carrefour. By combining the Boltanski and Thevenot polity model with the neo-institutionalist approach, we examine both the discourses and the practices that deal with low-carbon energy. These theoretical analyses are then used to understand the actual behaviours as well as the effective strategies that are initiated by retailers in respect of low-carbon activities. Finally, we discuss the place the integrated retailers grant to the wider issue of climate change.

Keywords: sobriété carbone, grande distribution, théorie des cités, néo-institutionnalisme, analyse de discours, low-carbon, retailers, polity model, neo-institutionalism, discourse analysis, baja emisión de carbono, grandes distribuidores, teoría de las ciudades, neo-institucionalismo, análisis del discurso

This article examines the forms of intimate transactions that urban youth in Côte d'Ivoire engage in as a means to mitigate the fragility of their socioeconomic situation. While a deterioration in the socioeconomic integration of youth and a decrease in the age at first union have marked past decades, the field of intimate and romantic relationships represent a privileged vantage point to understand the ways in which the process of socio-generational changes operate. Based on data from an ethnographic field study conducted in an informal settlement of Abidjan, the analysis focuses on the manner in which unmarried female youth relate to the prevailing ideology of heterosexual love and emotional attachment that inform the non-marital and extra-marital relations of their elders.

Keywords: agentivité, changement sociogénérationnel, jeunes, transactions intimes, Côte d'Ivoire

AbstractUsing a variety of archival sources and statistics compiled from military hospital records, the author examines the origin and dissemination of influenza in Canada during the “Spanish” influenza pandemic of 1918. He argues that pandemic influenza did not originate with soldiers returning from the First World War but instead traces the spread of the virus to American soldiers on their way overseas. The author posits that in Canada, the disease was then disseminated by the movement of Canadian soldiers as the war effort was widened to include a new commitment to mount an expeditionary force to Siberia. The author concludes that the physical path of the 1918 influenza pandemic in Canada is best understood as the result of a widening of the war effort at the expense of public health rather than as the inevitable consequence of the war's end.

The purpose of the present paper is to move closer to two registers of knowledge : SMEs' offshoring and SMEs' networks. In order to, the Uppsala model and isomorphism concept to highlight the role of networks, inter-organizational or interpersonal, on SMEs' offshoring decisions.This analysis of the literature will be confronted to a qualitative study realized on two SMEs belonging to the same network.The results shows that networks can encourage a SMEs' offshoring-induced via a mimetic isomorphism and can stop this strategy via a coercive isomorphism.

Keywords: Effet réseau, PME, Délocalisation, Modèle Uppsala, Isomorphisme, Network effects, SMEs, Offshoring, Uppsala model, Isomorphism, Efecto de red, PyME, Deslocalizacion, Modelo de Uppsala, Isomorphismo

AbstractTranslating modes are linked to historical periods as well as to connected philosophies of history. Among them transhistoricism aims to create a dialogue between distant historical situations, keeping from the past what is still relevant and enlightening both translated and translating worlds. This paper presents several philosophical and literary perspectives on transhistoricism, revisiting the notions of empathy and sacredness and their application for translation studies.

Keywords: historicisme, temporalité, empathie, culture, altérité, historicism, temporality, empathy, culture, otherness