Material Flow Accounting in Chile, Ecuador, Mexico and Peru (1980-2000)

In this paper we compare the resource flows of Chile, Ecuador, Mexico and Peru between 1980 and 2000. In this time span, the domestic extraction of materials increased in the four countries, mainly due to the mining sector in Chile and Peru, biomass and oil in Ecuador and construction minerals in Mexico. Imports and exports increased too, due to the increasing integration in the international markets, prompted by the liberalization policies undertaken by the four countries between the late 1970s and the late 1990s. The four countries had a negative physical trade balance for most of the period analyzed, meaning that their exports exceeded their imports in terms of weight. However, the increase of imports reduced the physical deficit in Chile, Mexico and Peru. Ecuador’s physical deficit was the highest and did not decrease in the period analyzed. Also, a diversification of exports away from bulk commodities could be observed in Chile and Mexico, and to a lesser extent in Peru, whereas in Ecuador the export sector remained mainly based on oil and biomass. More research is needed to explore the environmental effects of this phenomenon. Also, the indirect flows associated to the direct physical flows deserve to be subject to further analysis.

Role of two Triatoma (Hemiptera: Reduviidae: Triatominae) species in the transmission of Trypanosoma cruzi (Kinetoplastida: Trypanosomatidae) to man in the West Coast of Mexico

From August 1997 to August 1998, 334 specimens of Triatoma longipennis and 62 of T. picturata were collected in four groups of localities placed in the zone from Guadalajara, Jalisco to Tepic, Nayarit, in the West Coast of Mexico. Most T. longipennis were collected outdoors (69.2%) while most T. picturata (58.1%) were collected indoors. All collected specimens were examined for Trypanosoma cruzi infection, which was detected on 98 (29.3%) T. longipennis and 17 (27.4%) T. picturata. This study confirms the role of T. longipennis and T. picturata as some of the main T. cruzi vectors to humans in Mexico. Habitation Infestation Rate with T. longipennis was of 0.09 and with T. picturata was of 0.03 and the predominating ecotopes were pile of blocks, chicken coops, pigsties, wall crawls and beds.

Review of the Diploma in Social Work (JM Consulting Report) (PDF 97 KB)

Review of the Diploma in Social Work (JM Consulting Report)

High prevalence anti-Trypanosoma cruzi antibodies, among blood donors in the State of Puebla, a non-endemic area of Mexico

Blood transfusion is the second most common transmission route of Chagas disease in many Latin American countries. In Mexico, the prevalence of Chagas disease and impact of transfusion of Trypanosoma cruzi-contaminated blood is not clear. We determined the seropositivity to T. cruzi in a representative random sample, of 2,140 blood donors (1,423 men and 647 women, aged 19-65 years), from a non-endemic state of almost 5 millions of inhabitants by the indirect hemagglutination (IHA) and enzyme linked immunosorbent assay (ELISA) tests using one autochthonous antigen from T. cruzi parasites, which were genetically characterized like TBAR/ME/1997/RyC-V1 (T. cruzi I) isolated from a Triatoma barberi specimen collected in the same locality. The seropositivity was up to 8.5% and 9% with IHA and ELISA tests, respectively, and up to 7.7% using both tests in common. We found high seroprevalence in a non-endemic area of Mexico, comparable to endemic countries where the disease occurs, e.g. Brazil (0.7%), Bolivia (13.7%) and Argentina (3.5%). The highest values observed in samples from urban areas, associated to continuous rural emigration and the absence of control in blood donors, suggest unsuspected high risk of transmission of T. cruzi, higher than those reported for infections by blood e.g. hepatitis (0.1%) and AIDS (0.1%) in the same region.

Trypanosoma cruzi isolates from Mexican and Guatemalan acute and chronic chagasic cardiopathy patients belong to Trypanosoma cruzi I

Trypanosoma cruzi is classified into two major groups named T. cruzi I and T. cruzi II. In the present work we analyzed 16 stocks isolated from human cases and four isolated from triatomines from diverse geographical origins (Mexico and Guatemala). From human cases four were acute cases, six indeterminates, and six from chronic chagasic cardiophatic patients with diagnosis of dilated cardiomyopathy established based on the left-ventricular end systolic dimension and cardiothoracic ratio on chest X-radiography and impaired contracting ventricle and different degree conduction/rhythm aberrations. DNA samples were analyzed based on mini-exon (ME) polymorphism, using a pool of three oligonucleotide for the amplification of specific intergenic region of T. cruzi ME gene. All the Mexican and Guatemalan isolates regardless their host or vector origin generated a 350 bp amplification product. In conclusion T. cruzi I is dominant in Mexico and Guatemala even in acute and chronic chagasic cardiopathy patients. To our knowledge, this is the first study describing predominance of T. cruzi I in human infection for North and Central America.

Clinical forms of Trypanosoma cruzi infected individuals in the chronic phase of Chagas disease in Puebla, Mexico

In Mexico, despite the relatively high seroprevalence of Trypanosoma cruzi infection in humans in some areas, reported morbidity of Chagas disease is not clear. We determined clinical stage in 71 individuals seropositive to T. cruzi in the state of Puebla, Mexico, an area endemic for Chagas disease with a reported seroprevalence of 7.7%. Diagnosis of Chagas disease was made by two standardized serological tests (ELISA, IHA). Individuals were stratified according to clinical studies. All patients were submitted to EKG, barium swallow, and barium enema. Groups were identified as indeterminate form (IF) asymptomatic individuals without evidence of abnormalities (n = 34 cases); those with gastrointestinal alterations (12 patients) including symptoms of abnormal relaxation of the lower esophageal sphincter and absent peristalsis in the esophageal body, grade I megaesophagus, and/or megacolon; patients with clinical manifestations and documented changes of chronic Chagas heart disease who were subdivided as follows: mild (8 patients) - mild electrocardiographic changes of ventricular repolarization, sinus bradychardia); moderate (6 patients) - left bundle branch block, right bundle branch block associated with left anterior fascicular block); severe (8 patients) - signs of cardiomegaly, dilated cardiomyopathy); and the associated form (3 cases) that included presence of both cardiomyopathy and megaesophagus. These data highlight the importance of accurate evaluation of the prevalence and clinical course of Chagas disease in endemic and non-endemic areas of Mexico.

Geographic patterns in the distribution of social systems in terrestrial arthropods.

The role of ecology in the evolution and maintenance of arthropod sociality has received increasing research attention in recent years. In some organisms, such as halictine bees, polistine wasps, and social spiders, researchers are investigating the environmental factors that may contribute to high levels of variation in the degree of sociality exhibited both among and within species. Within lineages that include only eusocial members, such as ants and termites, studies focus more on identifying extrinsic factors that may contribute to the dramatic variation in colony size, number of queens, and division of labour that is evident across these species. In this review, I propose a comparative approach that seeks to identify environmental factors that may have a common influence across such divergent social arthropod groups. I suggest that seeking common biogeographic patterns in the distribution of social systems or key social traits may help us to identify ecological factors that play a common role in shaping the evolution of sociality across different organisms. I first review previous studies of social gradients that form along latitudinal and altitudinal axes. Within families and within species, many organisms show an increasing degree of sociality at lower latitudes and altitudes. In a smaller number of cases, organisms form larger groups or found nests cooperatively at higher latitudes and altitudes. I then describe several environmental factors that vary consistently along such gradients, including climate variables and abundance of predators, and outline their proposed role in the social systems of terrestrial arthropods. Finally, I map distributions of a social trait against several climatic factors in five case studies to demonstrate how future comparative studies could inform empirical research.

Spinitectus osorioi (Nematoda: Cystidicolidae) in the Mexican endemic fish Atherinella alvarezi (Atherinopsidae) from the Atlantic River drainage system in Chiapas, Southern Mexico

Specimens of Spinitectus osorioi Choudhury and Pérez-Ponce de León, an intestinal nematode species previously considered to be specific to Chirostoma spp and endemic to some lakes in the Pacific drainage in Michoacán, were collected from the freshwater fish Atherinella alvarezi (Díaz-Pardo) (Atherinopsidae) of the Michol River near Palenque, Chiapas, Southern Mexico, which belongs to the Atlantic drainage system. Studies using light and scanning electron microscopy revealed some taxonomically important, previously unreported or erroneously reported features of S. osorioi, such as the location of the vulva, the actual number and distribution of postanal papillae and phasmids and the presence of a short median cuticular ridge anterior to the cloacal opening (in addition to two long subventral ridges). The recorded somewhat shorter spicules (420-465 and 105-111 μm) and mostly smaller eggs (33-36 × 18-20 μm) as compared to the original species description may be due to a different type of host, geographical region or generally smaller body measurements of these specimens. These biometrical differences are considered to be within the limits of the intraspecific variability of S. osorioi. A key to species of Spinitectus parasitizing freshwater fishes in Mexico is provided.

Anti-impérialisme et nouvelle gauche radicale dans la Suisse des années 68

Cette thèse entend apporter un éclairage sur l'histoire politique et sociale de la Suisse des années 68, en étudiant l'articulation entre les mouvements anti-impérialistes et la nouvelle gauche radicale, alors foisonnante. Il s'agit d'analyser cette période de contestation au prisme de l'anti-impérialisme révolutionnaire, lequel, dans le contexte de l'opposition à la guerre du Vietnam, a fortement imprégné le mouvement protestataire, en assignant notamment au tiers-monde le rôle de sujet de l'émancipation mondiale. Combinant une triple approche - chronologique, thématique et biographique - ce travail est structuré en quatre parties. La première partie esquisse un panorama des mouvements anti-impérialistes des années 1960 et 1970 en Suisse, avec une focalisation sur les «années anti-imp», entre 1968 et 1975. La deuxième interroge le rapport entre anti¬impérialisme et nouvelle gauche radicale, en proposant une typologie des principaux courants. La troisième partie s'attache à examiner le système de représentations du monde et de la Suisse véhiculé par le discours de l'extrême gauche. Prenant pour objet le militantisme, la dernière partie esquisse un portrait de groupe de la « génération anti-imp », fondé sur une enquête prosopographique et sur un corpus d'entretiens réalisés avec des militants de l'époque. L'étude révèle que l'anti-impérialisme a fourni à la contestation soixante-huitarde un cadre conceptuel et analytique, un facteur de structuration, ainsi qu'un vecteur de mobilisation. Il a en particulier permis à la gauche radicale suisse d'inscrire sa lutte anticapitaliste locale dans un horizon global d'émancipation. L'analyse de l'anti-impérialisme révolutionnaire, qui a connu son apogée dans les années 68 avant de connaître un déclin rapide et presque total, invite à appréhender cette « décennie mouvementée » comme la fin d'un long cycle politique. -- This thesis aims to shed light on the social and political history of Switzerland in the 1960s and 1970s by studying the relationship between anti-imperialist movements and the emerging new radical left. It analyses this time of rebellion through the prism of revolutionary anti-imperialism. In the context of opposition to the Vietnam War, anti-imperialism strongly influenced protest movements, notably by assigning to the Third World the role of main actor in the fight for global emancipation. Combining a threefold approach - chronological, thematic and biographical - this work is structured in four parts. The first part provides a panorama of the anti-imperialist movements of the long 1960s in Switzerland with a focus on the « anti-imp years » between 1968 and 1975. The second part questions the relationship between anti-imperialism and the new radical left and proposes a typology of its main currents. The third part examines how the radical left's discourse represented the world, and Switzerland in particular. The last part addresses the question of activism and outlines a group portrait of the « anti-imp generation » based on a prosopographical study and on a body of interviews with former activists. This study reveals that anti-imperialism, besides serving as an agent of mobilization, provided a conceptual and ideological framework, as well as a structuring factor, to the protest movements. In particular, it enabled the Swiss radical left to fit its local anti-capitalist struggle into a global horizon of emancipation. This analysis of revolutionary anti- imperialism, which had its heyday in the 1960s and 1970s before experiencing a rapid and almost total decline, thus invites us to see this « turbulent decade » as the end of a long political cycle.

Appropriation of technology in "non-western" societies: an approximation to the case of Bulgaria

The principal focus of the PhD thesis lies in the Social Software area and the appropriation of technology in "non-Western" societies taking the example of Bulgaria. The term "non-Western" is used to explain places considered technologically underdeveloped. The aims have been to capture how Bulgarian users creatively interpret and appropriate Internet identifying the sociocultural, political and subjective conditions in which that appropriation occurs, to identify emerging practices based on the interpretation and use of Internet and the impact they had on society and what conditions could influence the technological interpretation and the meaning these practices had for both users and social configuration of Internet as media in Bulgaria. An ethnographic approach has been used simultaneously in different online and offline contexts. On the one hand, this study is based on exploration of the Bulgarian Internet Space through online participant observation in forums and websites reviews and on the other hand, on semi-structured interviews with different types of users of the virtual platforms found, made both face to face and online and finally online participant observation at the same platforms. It is based on some contributions of the ethnographic work of Christine Hine in virtual environments and the notions of time and space of Barbara Czarniawska contextualized in the modern form of organization that occurs in a network of multiple and fragmented contexts across many movements.

High prevalence of occult hepatitis B virus genotype H infection among children with clinical hepatitis in west Mexico

Studies on the prevalence of infection with hepatitis B virus (HBV) among children are scarce in Latin American countries, especially in Mexico. This study was aimed to investigate the prevalence of HBV infection, occult hepatitis B infection (OBI) and HBV genotypes among children with clinical hepatitis. In total, 215 children with clinical hepatitis were evaluated for HBV infection. HBV serological markers and HBV DNA were analysed. OBI diagnosis and HBV genotyping was performed. HBV infection was found in 11.2% of children with clinical hepatitis. Among these HBV DNA positive-infected children, OBI was identified in 87.5% (n = 21/24) of the cases and 12.5% (n = 3/24) were positive for both HBV DNA and hepatitis B surface antigen. OBI was more frequent among children who had not been vaccinated against hepatitis B (p < 0.05) than in those who had been vaccinated. HBV genotype H was prevalent in 71% of the children followed by genotype G (8%) and genotype A (4%). In conclusion, OBI is common among Mexican children with clinical hepatitis and is associated with HBV genotype H. The results show the importance of the molecular diagnosis of HBV infection in Mexican paediatric patients with clinical hepatitis and emphasise the necessity of reinforcing hepatitis B vaccination in children.

The combination of social and personal contexts affects dominance hierarchy development in shore crabs, Carcinus maenas

Many animals that live in groups maintain competitive relationships, yet avoid continual fighting, by forming dominance hierarchies. We compare predictions of stochastic, individual-based models with empirical experimental evidence using shore crabs to test competing hypotheses regarding hierarchy development. The models test (1) what information individuals use when deciding to fight or retreat, (2) how past experience affects current resource-holding potential, and (3) how individuals deal with changes to the social environment. First, we conclude that crabs assess only their own state and not their opponent's when deciding to fight or retreat. Second, willingness to enter, and performance in, aggressive contests are influenced by previous contest outcomes. Winning increases the likelihood of both fighting and winning future interactions, while losing has the opposite effect. Third, when groups with established dominance hierarchies dissolve and new groups form, individuals reassess their ranks, showing no memory of previous rank or group affiliation. With every change in group composition, individuals fight for their new ranks. This iterative process carries over as groups dissolve and form, which has important implications for the relationship between ability and hierarchy rank. We conclude that dominance hierarchies emerge through an interaction of individual and social factors, and discuss these findings in terms of an underlying mechanism. Overall, our results are consistent with crabs using a cumulative assessment strategy iterated across changes in group composition, in which aggression is constrained by an absolute threshold in energy spent and damage received while fighting.

Highly variable social organisation of colonies in the ant Formica cinerea.

Social organisation of colonies was examined in the ant Formica cinerea by estimating the coefficient of genetic relatedness among worker nest mates. The estimates based on microsatellite genotypes at three loci ranged from values close to zero to 0.61 across the populations studied in Finland. These results showed that a fundamental feature of colonies, the number of reproductive queens, varied greatly among the populations. Colonies in some populations had a single queen, whereas the nests could have a high number number of queens in other populations. There was a weak but non-significant correlation between the genetic and metric distance of nests within two populations with intermediate level of relatedness. Differentiation among nearby populations (within the dispersal distance of individuals) in one locality indicated limited dispersal or founder effects. This could occur when females are philopatric and stay in the natal polygynous colony which expands by building a network of nest galleries within a single habitat patch.