Campesino Participation in Rural Paraguay: Practical and Theoretical Challenges

In 1997, the community of Guayaki-Cua, Paraguay underwent a dramatic political and social transformation allowing campesinos to take a more active role in decisionmaking processes. This change established safety and security for local residents, and brought about the involvement of the Paraguayan government, nongovernmental organizations and residents to begin development work in the form of infrastructure projects. The end of the Stroessner dictatorship in 1989 signaled the end of autocratic rule and ushered in the neoliberal perspective advocating private property, free trade, and other measures to bring about the democratization of Latin America economies to foster growth and participation. In the late 1990s after a series of economic crashes in Brazil and Argentina the neoliberal model of development lost support from local communities. Rural communities such as Guayaki-Cua began confronting the established U.S. supported Colorado party system that changed its tactics after the dictatorship and favored neoliberal development. GuayakiCua is a community in transition where campesinos are making efforts to take part in a true grassroots democratic process, which favors just development while dealing with Colorado rule and neoliberal promotion as campesinos make strides towards increasing participation through grassroots methods

The Charismatic Revolutionary Leadership Trajectories of Fidel Castro and Lázaro Cárdenas: From Guerrillas to Heads of State in the Age of US Imperialism

After attempting to overthrow the government of Fulgencio Batista in 1953, Fidel Castro fled to Mexico where he, his brother, Raul Castro, Ernesto Che Guevara, and other revolutionaries were later jailed by the Mexican government under the orders of the Batista dictatorship to be returned to Cuba. Using his knowledge of the Mexican Revolution, Castro wrote a letter asking for help from former president and revolutionary general, Lázaro Cárdenas, appealing to his sense of revolutionary history and social justice. Cárdenas was impressed by this young revolutionary and worked to obtain political asylum for he and his comrades. This allowed Castro to enter Texas clandestinely in order to collect funds for the Cuban Revolution. This chance encounter of two revolutionaries is not well known in the annals of Mexico and Cuba, yet provides us with an important historical interaction between two dynamic and charismatic leaders who were uniquely loved by their respective publics, and often clashed with attempted international interventions. Moreover, their relationship did not end with the release of Castro in 1956 as they continued to influence each other. Yet, historians have largely ignored the connection between Castro and Cárdenas. I argue that both men were effective revolutionary leaders who followed similar trajectories as they became highly revered for their charismatic leadership based on their combat experience, victory over national and international challenges, leadership of their nations, and the nationalization of petroleum which institutionalized both revolutions

Spitzer Warm Mission Transition and Operations

Following the successful dynamic planning and implementation of IRAC Warm Instrument Characterization activities, transition to Spitzer Warm Mission operations has gone smoothly. Operation teams procedures and processes required minimal adaptation and the overall composition of the Mission Operation System retained the same functionality it had during the Cryogenic Mission. While the warm mission scheduling has been simplified because all observations are now being made with a single instrument, several other differences have increased the complexity. The bulk of the observations executed to date have been from ten large Exploration Science programs that, combined, have more complex constraints, more observing requests, and more exo-planet observations with durations of up to 145 hours. Communication with the observatory is also becoming more challenging as the Spitzer DSN antenna allocations have been reduced from two tracking passes per day to a single pass impacting both uplink and downlink activities. While IRAC is now operating with only two channels, the data collection rate is roughly 60% of the four-channel rate leaving a somewhat higher average volume collected between the less frequent passes. Also, the maximum downlink data rate is decreasing as the distance to Spitzer increases requiring longer passes. Nevertheless, with well over 90% of the time spent on science observations, efficiency has equaled or exceeded that achieved during the cryogenic mission

Order N photonic band structures for metals and other dispersive materials

We show, for the first time, how to calculate photonic band structures for metals and other dispersive systems using an efficient Order N scheme. The method is applied to two simple periodic metallic systems where it gives results in close agreement with calculations made with other techniques. Further, the approach demonstrates excellent numerical stablity within the limits we give. Our new method opens the way for efficient calculations on complex structures containing a whole new class of material.Comment: Four pages, plus seven postscript figures. Submitted to Physical Review Letter

Robotics and Dynamic Image Analysis for Studies of Gene Expression in Plant Tissues

Gene expression in plant tissues is typically studied by destructive extraction of compounds from plant tissues for in vitro analyses. The methods presented here utilize the green fluorescent protein (gfp) gene for continual monitoring of gene expression in the same pieces of tissues, over time. The gfp gene was placed under regulatory control of different promoters and introduced into lima bean cotyledonary tissues via particle bombardment. Cotyledons were then placed on a robotic image collection system, which consisted of a fluorescence dissecting microscope with a digital camera and a 2-dimensional robotics platform custom-designed to allow secure attachment of culture dishes. Images were collected from cotyledonary tissues every hour for 100 hours to generate expression profiles for each promoter. Each collected series of 100 images was first subjected to manual image alignment using ImageReady to make certain that GFP-expressing foci were consistently retained within selected fields of analysis. Specific regions of the series measuring 300 x 400 pixels, were then selected for further analysis to provide GFP Intensity measurements using ImageJ software. Batch images were separated into the red, green and blue channels and GFP-expressing areas were identified using the threshold feature of ImageJ. After subtracting the background fluorescence (subtraction of gray values of non-expressing pixels from every pixel) in the respective red and green channels, GFP intensity was calculated by multiplying the mean grayscale value per pixel by the total number of GFP-expressing pixels in each channel, and then adding those values for both the red and green channels. GFP Intensity values were collected for all 100 time points to yield expression profiles. Variations in GFP expression profiles resulted from differences in factors such as promoter strength, presence of a silencing suppressor, or nature of the promoter. In addition to quantification of GFP intensity, the image series were also used to generate time-lapse animations using ImageReady. Time-lapse animations revealed that the clear majority of cells displayed a relatively rapid increase in GFP expression, followed by a slow decline. Some cells occasionally displayed a sudden loss of fluorescence, which may be associated with rapid cell death. Apparent transport of GFP across the membrane and cell wall to adjacent cells was also observed. Time lapse animations provided additional information that could not otherwise be obtained using GFP Intensity profiles or single time point image collections

Effectiveness of Cabs for Dust and Silica Control on Mobile Mining Equipment

The Mine Safety and Health Administration (MSHA) has conducted a study to evaluate the effectiveness of cabs for controlling silica dust exposure during operation of mobile mining equipment. This study focused on bulldozers, front -end loaders and haul trucks, was conducted at surface coal mining operations and underground metal and nonmetal mining operations. Each piece of equipment tested was equipped with a cab. The vehicles sampled were from a range of manufacturers having different types of filter media and air intake configurations. The purpose of this study was to determine the reduction of dust and silica exposure that could be achieved through the use of a well-maintained cab. For each piece of equipment, dust and silica concentrations inside and outside the cab were determined and compared. In some cases, filtration efficiencies could be calculated. A properly designed environmental cab is sealed, has an intake air filtration system, and a heating and cooling system. Cabs should have good seals around the doors and windows. Factors such as cab pressurization filtration systems, filter media, and maintenance practices were also examined. In some cases, dust and silica reduction of 90 to 95% were observed

Impact of extracellular folic acid levels on oviductal gene expression

Folate plays a specific role as methyl donor for nucleotide synthesis and genomic methylation patterns, which in turn are important epigenetic determinants in gene expression. Previous studies have revealed the presence of folate in bovine oviductal fluid as well as the existence of a fine-tuned regulation of the gene expression of folate receptors and transporters in bovine oviduct epithelial cells (BOECs). However, the functional implications of folate in the oviduct remain unknown. The present study aimed to assess the effect of folic acid (FA) on expression levels of selected genes that potentially respond to the folate status in in vitro BOECs. To obtain an insight into the optimization of a culture system for assays, gene expression of folate receptors and transporters was compared between BOECs grown in monolayers and in suspension. The results showed that BOECs from isthmus and ampulla in suspension culture better preserved the region-dependent gene expression profile than in monolayers. Subsequently, BOECs from both anatomical regions were separately cultured in suspension for 24 h assaying different FA concentrations: I) TCM-199 (control); II) TCM-199 + 1 μM FA (similar to the oviduct concentration); III) TCM-199 + 10 μM FA and IV) TCM-199 + 100 μM FA. Expression analysis of genes related to important cellular processes including folate transport, DNA methylation, cell-cell interaction, antioxidant activity and signaling pathways was performed in BOECs using RT-qPCR. Our data demonstrated that addition of 1 μM FA did not affect mRNA levels of most genes analyzed. In contrast, BOECs cultured with 10 μM FA exhibited increased mRNA expression levels of genes involved in folate intake, DNA methylation and antioxidant protection. It is worth noting that at 100 μM FA, transcriptional response in BOECs mainly resulted in decreased mRNA levels of the majority of the genes assayed. Interestingly, cytotoxicity analysis showed a similar LDH activity in the culture media of the experimental groups, indicating that cell integrity was not affected by the FA concentrations assayed. In conclusion, our findings suggest that folate can affect BOECs, promoting changes in gene activity in a framework of functional readjustments in response to environmental conditions.Fil: Garcia, Elina Vanesa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet Noa Sur. Instituto Superior de Investigaciones Biológicas. Grupo de Investigación y Desarrollo del Noroeste Argentino | Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas. Grupo de Investigación y Desarrollo del Noroeste Argentino; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Biología; ArgentinaFil: Mansilla, Mariano J.. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Biología; ArgentinaFil: Leblanc, Jean Guy Joseph. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Barrera, Antonio Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet Noa Sur. Instituto Superior de Investigaciones Biológicas. Grupo de Investigación y Desarrollo del Noroeste Argentino | Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas. Grupo de Investigación y Desarrollo del Noroeste Argentino; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Biología; Argentin

Potential for Integrating Entry Guidance into the Multi-Disciplinary Entry Vehicle Optimization Environment

The state-of-the-art in vehicle design decouples flight feasible trajectory generation from the optimization process of an entry spacecraft shape. The disadvantage to this decoupled process is seen when a particular aeroshell does not meet in-flight requirements when integrated into Guidance, Navigation, and Control simulations. It is postulated that the integration of a guidance algorithm into the design process will provide a real-time, rapid trajectory generation technique to enhance the robustness of vehicle design solutions. The potential benefit of this integration is a reduction in design cycles (possible cost savings) and increased accuracy in the aerothermal environment (possible mass savings). This work examines two aspects: 1) the performance of a reference tracking guidance algorithm for five different geometries with the same reference trajectory and 2) the potential of mass savings from improved aerothermal predictions. An Apollo Derived Guidance (ADG) algorithm is used in this study. The baseline geometry and five test case geometries were flown using the same baseline trajectory. The guided trajectory results are compared to separate trajectories determined in a vehicle optimization study conducted for NASA's Mars Entry, Descent, and Landing System Analysis. This study revealed several aspects regarding the potential gains and required developments for integrating a guidance algorithm into the vehicle optimization environment. First, the generation of flight feasible trajectories is only as good as the robustness of the guidance algorithm. The set of dispersed geometries modelled aerodynamic dispersions that ranged from +/-1% to +/-17% and a single extreme case was modelled where the aerodynamics were approximately 80% less than the baseline geometry. The ADG, as expected, was able to guide the vehicle into the aeroshell separation box at the target location for dispersions up to 17%, but failed for the 80% dispersion cases. Finally, the results revealed that including flight feasible trajectories for a set of dispersed geometries has the potential to save mass up to 430 kg