Since the redemocratization of much of Latin America in the 1980s and a regional wave of anti-austerity protests in the 1990s, social movement studies has become an important part of sociological, ...political, and anthropological scholarship on the region. The subdiscipline has framed debates about formal and informal politics, spatial and relational processes, as well as economic changes in Latin America. While there is an abundant literature on particular movements in different countries across the region, there is limited coverage of the approaches, debates, and theoretical understandings of social movement studies applied to Latin America. In The Oxford Handbook of Latin American Social Movements, Federico M. Rossi presents a survey of the broad range of theoretical perspectives on social movements in Latin America. Bringing together a wide variety of viewpoints, the Handbook includes five sections: theoretical approaches to social movements, as applied to Latin America; processes and dynamics of social movements; major social movements in the region; ideational and strategic dimensions of social movements; and the relationship between political institutions and social movements. Covering key social movements and social dynamics in Latin America from the late nineteenth century to the twenty-first century, The Oxford Handbook of Latin American Social Movements is an indispensable reference for any scholar interested in social movements, protest, contentious politics, and Latin American studies.
Exopolysaccharides (EPSs) are an important class of biopolymers with great ecological importance. In natural environments, they are a common feature of microbial biofilms, where they play key ...protective and structural roles. As the primary colonizers of constrained environments, such as desert soils and lithic and exposed substrates, cyanobacteria are the first contributors to the synthesis of the EPSs constituting the extracellular polymeric matrix that favors the formation of microbial associations with varying levels of complexity called biofilms. Cyanobacterial colonization represents the first step for the formation of biofilms with different levels of complexity. In all of the possible systems in which cyanobacteria are involved, the synthesis of EPSs contributes a structurally-stable and hydrated microenvironment, as well as chemical/physical protection against biotic and abiotic stress factors. Notwithstanding the important roles of cyanobacterial EPSs, many aspects related to their roles and the relative elicited biotic and abiotic factors have still to be clarified. The aim of this survey is to outline the state-of-the-art of the importance of the cyanobacterial EPS excretion, both for the producing cells and for the microbial associations in which cyanobacteria are a key component.
The selectivity of neuronal responses arises from the architecture of excitatory and inhibitory connections. In the primary visual cortex, the selectivity of a neuron in layer 2/3 for stimulus ...orientation and direction is thought to arise from intracortical inputs that are similarly selective
. However, the excitatory inputs of a neuron can have diverse stimulus preferences
, and inhibitory inputs can be promiscuous
and unselective
. Here we show that the excitatory and inhibitory intracortical connections to a layer 2/3 neuron accord with its selectivity by obeying precise spatial patterns. We used rabies tracing
to label and functionally image the excitatory and inhibitory inputs to individual pyramidal neurons of layer 2/3 of the mouse visual cortex. Presynaptic excitatory neurons spanned layers 2/3 and 4 and were distributed coaxial to the preferred orientation of the postsynaptic neuron, favouring the region opposite to its preferred direction. By contrast, presynaptic inhibitory neurons resided within layer 2/3 and favoured locations near the postsynaptic neuron and ahead of its preferred direction. The direction selectivity of a postsynaptic neuron was unrelated to the selectivity of presynaptic neurons, but correlated with the spatial displacement between excitatory and inhibitory presynaptic ensembles. Similar asymmetric connectivity establishes direction selectivity in the retina
. This suggests that this circuit motif might be canonical in sensory processing.
This paper considers the problem of routing and rebalancing a shared fleet of autonomous (i.e., self-driving) vehicles providing on-demand mobility within a
capacitated
transportation network, where ...congestion might disrupt throughput. We model the problem within a network flow framework and show that under relatively mild assumptions the rebalancing vehicles, if properly coordinated, do not lead to an increase in congestion (in stark contrast to common belief). From an algorithmic standpoint, such theoretical insight suggests that the problems of routing customers and rebalancing vehicles can be
decoupled
, which leads to a computationally-efficient routing and rebalancing algorithm for the autonomous vehicles. Numerical experiments and case studies corroborate our theoretical insights and show that the proposed algorithm outperforms state-of-the-art point-to-point methods by avoiding excess congestion on the road. Collectively, this paper provides a rigorous approach to the problem of congestion-aware, system-wide coordination of autonomously driving vehicles, and to the characterization of the sustainability of such robotic systems.
Combining agonistic pluralism and social movements literature with trust studies, I propose a conceptualization for how the organizational dilemma is tackled in social movements. Defined as a ...trust-building organizational learning process, I show the role-played by social trust—meaning, the construction of the relational boundaries of a shared goal without diluting the heterogeneity of self-identities and interests—as an organizational prerequisite for democratic organization of a political group. Empirically, I identify four alternative pathways to the (democratic) organizational dilemma: innovation through new organizational models; repetition of past experiences; reformulation of practices; and emulation of previous organizational models.
•Renewable hydrogen reacts with flue gas for ammonia and methane synthesis.•Experimental activities show a carbon dioxide conversion to methane equal to 95.55%.•Carbon and energy footprint of ammonia ...and methane synthesis were calculated.•For 1 kg of flue gas the carbon footprint is 0.7819 kgCO2eq and the energy footprint is 50.73 MJ.•The process is a viable carbon recycling path in case of renewable energy excess use.
The present paper aims at assessing the carbon and energy footprint of an innovative process for carbon dioxide recycling, with flue gas as feedstock of nitrogen and carbon dioxide. Nitrogen is converted into ammonia through the Haber-Bosch process and carbon dioxide into methane via Sabatier reaction using hydrogen produced by renewable electricity excess. Carbon and energy footprint analysis of the process was assessed based on experimental data related to hydrogen production by electrolysis, methane synthesis via Sabatier reaction, energy consumption and energy output of the process units for flue gas separation, carbon dioxide methanation and ammonia synthesis. A Life Cycle Assessment method is applied, based on the experimental and computational data, both in case of renewable electricity excess and electricity from the grid. Results show that in case of renewable electricity excess, for a functional unit of 1 kg of treated flue gas, the specific carbon footprint is 0.7819 kgCO2eq and energy footprint is 50.73 MJ, which correspond to 4.012 kg and 260.3 MJ per 1 kg of produced hydrogen. In case of electricity from the grid, the specific carbon footprint is 1.550 kgCO2eq and energy footprint is 59.12 MJ per flue gas mass unit. If the carbon footprint is positive, the process indirectly leads to avoided emissions, ranging from 0.673 to 0.844 kgCO2eq kg−1fluegas, thus proving the sustainability of the proposed pathway.
This review article aims to describe the main applications of gas hydrates in industrial processes and the related advantages and limitations. In particular, gas storage, energy storage, gas ...transportation, final disposal of greenhouse gases, desalination, wastewater treatments, food concentration, and other technologies are described in detail. Similarly, the benefits and disadvantages of the solutions, currently adopted to improve the process efficiency, are discussed in the text. A particular focus on the use of additives and their capability to intervene during the formation of hydrates and on the replacement process is provided. The second part of the article deals with the use of small-chain hydrocarbons as aid gases during formation, to improve the efficiency and the competitivity of hydrate-based processes. First, the thermodynamic properties of hydrates, containing only these compounds, are described. Then, based on a collection of experimental data available elsewhere in the literature, their effect on the hydrate formation process, when present in the mixture, is shown and detailed. Finally, direct and experimental applications of these gases during hydrate-based processes are described to definitively prove the possibility of solving, partially or completely, most of the main limiting problems for the diffusion of hydrate-based technologies.
The use of carbon dioxide, originated from industrial processes, for gas hydrates production, is currently gaining the interest of researchers, due to the opportunity to increase the rate of methane ...recovery and, furthermore, to permanently store this greenhouse gas in solid form. However, the production of CO2 hydrates requires relatively high pressures and low temperatures and energy costs are often too elevated to make these applications feasible. The use of chemical promoters often allows to get around this problem and innumerable researches describe equilibrium condition for CO2 hydrates in the presence of the available and competitive promoter. This work deals with the consistent lack of information about the molecular and crystalline properties of these compounds, which play a crucial function in improving the efficiency of the process. In this research, CO2 hydrates were formed in the presence of THF and TBAB in the high-pressure optical cell. The Raman spectra and hydrates crystalline characteristics were observed in situ. The phase equilibrium results indicated that THF extended the temperature range for the stable presence of hydrates, and the optimal promoting concentration was 4.22 mol%. The same mass fraction of THF with NaCl solution still performed as a promoting effect with a narrow equilibrium temperature range. The structure of crystals was described with accuracy and the variation in crystals’ morphology associated with the presence of each specific additive, was characterized. The CO2-THF sII hydrate tended to form prismatic shaped crystals, and during the decomposition, the THF molecule separated from the clathrate cage, showing an internal collapse on the crystal scale. The CO2-TBAB semi-clathrate hydrate is columnar in shape and had a similar decomposition process. This work might help comprehend CO2 hydrate storage technology and could give theoretical basis for subsequent applications in the sector.
Neoliberalism changed the face of Latin America and left average citizens struggling to cope in many ways. Popular sectors were especially hard hit as wages declined and unemployment increased. The ...backlash to neoliberalism in the form of popular protest and electoral mobilization opened space for leftist governments to emerge. The turn to left governments raised popular expectations for a second wave of incorporation. Although a growing literature has analyzed many aspects of left governments, there is no study of how the redefinition of the organized popular sectors, their allies, and their struggles have reshaped the political arena to include their interests-until now. This volume examines the role played in the second wave of incorporation by political parties, trade unions, and social movements in five cases: Argentina, Bolivia, Brazil, Ecuador, and Venezuela. The cases shed new light on a subject critical to understanding the change in the distribution of political power related to popular sectors and their interests-a key issue in the study of postneoliberalism.
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