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Do myths ever die? Social-cultural changes and mythical transformations in Indigenous Amazonia: a dialogue with Peter Gow
Full text linkThis is the first Peter Gow Memorial Lecture, given at the University of St Andrews in February 2024. Based on the analysis of different versions of Wari’ myths (Rondônia, Brazil) collected over forty years, the paper has two central objectives. The first is to engage with Peter Gow’s analysis of the mythical transformations resulting from the historical changes experienced by the Piro/Yine Indigenous people of Peru. The second is to discuss Lévi-Strauss’s suggestion that a myth can “die” after successive transformations, exhausting itself, taking the form of romantic tale or legendary tradition
Final Project Reprot: Electrospinners
Full text linkThis report provides a comprehensive overview of the development of the Electrospinning Machine Year 2 project. In the year 1 iteration of the project, the previous team successfully produced nanofibers, but in an unaligned, random orientation due to the usage of a flat plate collector. Building upon the foundation laid by the previous team, this year\u27s effort focuses on enhancing the functionality of the existing electrospinning machine by improving the alignment of nanofibers and enabling the simultaneous projection of multiple polymer solutions. Key objectives include the design of a cylindrical collector subsystem, the development of a high-precision motor system, the integration of a dual-barrel syringe for modular solution ejection, and the establishment of metrics for evaluating fiber alignment.
At the core of the design is an in-house manufactured cylindrical collector made of aluminum, chosen for its conductivity, durability, and cost-effectiveness. Driven by a high-speed servo motor capable of reaching speeds between 2000-6000 rpm, this subsystem is designed to optimize nanofiber alignment while adhering to OSHA mechanical and electrical safety standards. The motor system includes a DC power supply, a PWM motor controller with adjustable speed settings, and a modular stand mechanism designed for future scalability and improved alignment precision.
The syringe pump subsystem features a dual-barrel syringe mechanism, allowing for the simultaneous ejection of multiple polymer solutions at controlled flow rates. This modular solution avoids significant modifications to the existing syringe pump system, reducing cost and complexity while meeting the objective of projecting multiple solutions. Needle tips and flow rates are optimized to achieve fiber diameters of approximately 200 nm, enhancing the system\u27s adaptability to various electrospinning applications.
Fiber alignment is quantified using MATLAB and ImageJ to evaluate and compare nanofiber orientation against the fiber alignment of the previous team’s sample. The goal is to achieve more aligned nanofibers by producing samples with a lower interquartile range for the angle distribution. A lower interquartile range (IQR) will show that the fibers are oriented within a smaller range of angles whereas a larger IQR will show that fibers are oriented across a wide range of angles. The color maps and histograms provided by ImageJ and the IQR provided by MATLAB will provide an analysis of the fiber alignment. Additionally, ImageJ will provide a measurement of the fiber diameters to ensure that fibers are produced with diameters of 200 nm ±20%.
Testing confirmed that the completed prototype met all project objectives and working criteria. The system is capable of producing aligned nanofibers with diameters of 200 nm ±20%, which has been successfully proven using image processing to quantify fiber alignment
Final Project Report: Plastic Wall-E Year 3
Full text linkRicardo Gonzalez Jurado visualizes a better future for the planet, one where plastic waste is not a pressing issue to the environment and the human race. As the sponsor, he set in motion the task to repurpose plastic to minimize damage from microplastics. Furthermore, he requested for this solution to be functional, leading to the idea of a plastic block that can be placed within a standard cement brick and be used in construction. This year’s design and solution builds upon the work of two past years. The design aims to produce plastic bricks that fit in the cell of a standard concrete block, maximize the plastic content while containing more than 0.5 kg of plastic, encapsulate the plastic from any outside elements, have no effect on the structural integrity of the cement bricks, and is within the allotted budget.
There are two main components to the design created this past year. The first component is the plastic brick design. The brick refers to the container that will hold the plastic and be placed into the cinder-blocks. This container uses compressed shredded plastic, a milk carton, and a waterproof sealant to encapsulate the plastic and ensure it protects the environment from the byproducts of plastic waste. A working prototype of this component was completed. The second aspect of the design is the machine that will output the brick. In this component, the process of making the brick is split up into subsystems that ensure the outcome is up to standard and efficient. It also needed to be usable in Guatemala, where Ricardo Gonzalez Jurado aims to further this work. The subsystems for the design consist of the compression mechanism and chamber, the securement, the sealant and removal from sealant, the drying process, and lastly the material preparation within the machine. Due to time constraints and the focus on the brick design last semester, the product for the machine design is a blueprint and details about the specifics of the design.
Six tests were performed to determine the success of each of the subsystems. Three tests determined the success of the brick design and the following three helped to shape the machine design. During the first semester, testing was performed on the compression method and the container for the plastic with an additional restraint test to support the container. Testing the compression ratio of the milk carton with wires for support resulted in a ratio of 2.25:1, the highest of the compression tests. It was also recorded that the wires did not experience any displacement, rendering them useless. The sealant was tested to ensure that it is water resistant. The brick parameters all passed their tests. Moving to the tests that determined the decisions around the machine, the primary test measured the clearance the final output brick had in two types of standard cinder blocks. The resulting brick passed this test with a range of clearance in the cells. The last two tests measured the same parameter: securement. The fifth test used our initial design and using a pass fail method measured if the brick could be within force after being secured. After brainstorming, the team re-designed the securement method to have less overall waste. After this, the brick went through the same test with the new method and passed.
The machine design assesses all criteria, both essential and optional, to meet the sponsor’s needs. Using subsystems that output the pre-designed brick, plastic waste can be repurposed and kept out of harm\u27s way. Future work will consist of building a machine prototype to test the designed subsystems. In addition, aspects of the design such as dimensions and efficiency will be further scrutinized to further enhance the machine
El sistema nainu de agricultura familiar: semillas de la memoria social y de la autonomía alimentaria en Gunayala (Panamá)
No full textLa presente investigación examina el sistema agroforestal familiar (nainu) del pueblo gunadule como un tejido de resistencia social, espiritual y ecológica frente a los procesos históricos y actuales de desposesión territorial y colapso climático. A partir de un enfoque etnográfico basado en métodos participativos y epistemologías indígenas, se analizan las prácticas, conocimientos y relaciones que sostienen la autonomía alimentaria y la regeneración del territorio en Gunayala. El estudio documenta los impactos de la transferencia tecnológica, la expansión de semillas híbridas y transgénicas, identificados como amenazas centrales para la continuidad de los cultivos tradicionales y la salvaguardia de semillas nativas. Frente a estos desafíos, los esfuerzos comunitarios por proteger semillas ancestrales in situ, revitalizar el sistema nainu y revalorizar sus usos alimentarios y medicinales destacan como estrategias de resiliencia y re-existencia. En diálogo con el “giro vegetal” en antropología se argumenta que las formas de vida indígenas no son vestigios del pasado, sino horizontes éticos y políticos que ofrecen claves para enfrentar el Antropoceno. El sistema agroforestal nainu, entendido como cosmotécnica y ecología del cuidado, constituye una vía concreta de re-existencia indígena y transición socioambiental desde los trópicos, aportando perspectivas críticas a los debates globales sobre justicia ambiental y seguridad alimentaria
The matter of production and forms of sharing: transformations of food economies in Lowland South America
No full textThis special issue of Tipití presents a critical examination of ‘food economies’ and their transformations within Indigenous communities in Lowland South America. Stemming from seminal ideas in its Anthropology that directly or indirectly discuss ‘food’ (and much of what goes along with it), this edited volume focuses on the materiality of relations as a strategic lens for understanding contemporary Indigenous lives and their transformations, according to how they are perceived by Indigenous peoples themselves and others such as health care professionals and the state. The articles explore how Indigenous foodways—from acquisition to consumption, including sharing and distribution—reveal key aspects of transformations that are deeply intertwined with kinship networks and relational logics, such as co-residence, commensality, and consubstantiality. The volume critically discusses technical constructs such as \u27food security,\u27 which does not adequately render nuanced Indigenous understandings of well-being that often prioritize joy, beauty, and vitality, as well as material conditions of the land, over technical nutritional intake measurements. Using rigorous ethnographic approaches and a variety of case studies, the contributors analyze the interplay of Indigenous sociocosmologies, kinship systems, and relatedness, as well as external forces—whether peaceful or disruptive—such as public policies, market dynamics, and the monetarization of exchange and relations of mutuality. The articles reveal Indigenous resilience, paths of changes, and strategies to maintain autonomy in a context of profound social transformations. They highlight how food systems are inextricably linked to broader sociopolitical and ecological alterations. The volume addresses methodological challenges, emphasizing the mandate to prioritize indigenous demands in their own perspectives. It advances a model for understanding traditional food systems and their interaction with international legislation and programs that define appropriate ways to eat, to perceive and address hunger, and related matters. These have an impact at the national level and are often at odds with local laws that protect Indigenous people’s ways of life. Thus, the edited volume underscores the multidimensional nature of food as a nexus that ties together sociality, care, communion, and conflict, as well as political agency. It offers profound insights into Indigenous knowledge systems and the vital role of native epistemologies for the production of contemporary communal living in Lowland South America
Age, provenance, and geochemical relationships amongst the Great Valley Group, Coast Range Ophiolite, and Franciscan subduction complex at Del Puerto Canyon, central California
No full textThe Great Valley Forearc (GVF) basin of California, USA, preserves an extensive rock record of the Jurassic–Paleogene tectonic development of the California segment of the North American Cordillera. We present new U-Pb geochronology, zircon and whole-rock geochemistry, and petrographic analyses from the Great Valley Group (GVG), Franciscan subduction complex, and Coast Range Ophiolite (CRO) in the northern San Joaquin Valley to better understand the timing and location of initial forearc sedimentation, and how sediment routing systems may have evolved during Cretaceous time. Basal GVG strata of the Knoxville Formation were deposited ca. 145–140 Ma and are separated by an ~40 m.y. unconformity with overlying strata of the Upper Cretaceous Panoche Formation. Pre-Mesozoic zircon grains are present in both the Knoxville and Panoche formations, but are sparse (0%–7%) compared to other GVG sandstones. Zircon geochemistry records felsic igneous sources (Th/U 0.9–0.2) during both periods of deposition, and epsilon Hf signatures reveal a shift from juvenile to more evolved sources between Knoxville and Panoche deposition. Whole-rock geochemistry shows increasing compositional maturity from latest Jurassic crystallization of the CRO to Early and Late Cretaceous deposition of the GVG. Integrating these data, we present a tectonic model for the northern San Joaquin portion of the GVF basin from ca. 145 Ma to 80 Ma that documents the onset of basin deposition and details sediment pathways during the Early to earliest Late Cretaceous. In addition, we discuss potential drivers for the ~40 m.y. unconformity within the San Joaquin Valley and implications of this work for global forearc basin processes
Fermentative processes of the agricultural food system in the Upper Rio Negro: ethnographic notes on feminine knowledge, intention, and agency in the production of fermented beverages
No full textThis article examines the fermentative processes at the core of the agricultural food system of the Upper Rio Negro, northwestern Amazon, highlighting women’s technical and social agency in the production of fermented beverages such as caxiri. Based on ethnographic fieldwork conducted among Baniwa and Tukano families between 2018 and 2019, the study explores how fermentation constitutes not merely a biochemical transformation of matter but a sociotechnical language through which women express intention, alliance, and distinction. The paper analyzes in detail two cases of caxiri preparation, showing how women’s manipulation of manioc, tubers, saliva, and utensils configures embodied knowledge transmitted primarily through uterine lines. In addition, it shows other modes of fermentative beverage production, of which caxiri is one. The mastery of fermentation illuminates female knowledge transmission, emphasizing women’s role in food preparation as a vital locus of symbolic power and social reproduction, within (and beyond) a patrilineal kinship system
Ädeeja: origem dos alimentos cultivados e práticas alimentares ye’kwana
No full textO artigo explora a ligação entre a cosmologia do povo Ye’kwana e suas práticas alimentares tradicionais, com base no conceito central de ädeeja, que representa os alimentos cultivados. Esse termo abrange mais do que a ideia de comida — ele carrega uma dimensão cosmológica e relacional, conectando humanos, espíritos, plantas e o território. Está ligado a uma rede de relações entre humanos, espíritos vegetais e saberes ancestrais. Representa a comida como elo com o cosmos, reforçando a interdependência entre os seres. Minha análise mostra que, para os Ye’kwana, alimentar-se é um ato cósmico, enraizado em narrativas, cantos e relações com seres não humanos. O conceito de ädeeja sintetiza essa visão: o alimento cultivado é sagrado, ancestral e relacional, dando significado complexo, amplo e relacional ao ato de “cultivar”. Ao cultivar a terra, os Ye’kwana cultivam também suas histórias, sua cosmologia e sua identidade como povo
As donas do fogo: parentesco, práticas alimentares e luta pela terra entre os Kaiowa e Guarani
No full textOs Guarani e Kaiowa apresentam uma relação sofisticada entre as práticas alimentares e a recuperação de territórios tradicionais em Mato Grosso do Sul (Brasil), protagonizada cotidianamente por mulheres indígenas. As mulheres guarani e kaiowa consideram o fogo como uma referência da casa de residência de um núcleo familiar e a palavra se apresenta como potência em seu fazer político. Elas são as “donas do fogo”. Compartilhando suas próprias substâncias corporais e acumulando aprendizados adquiridos no cuidado com pessoas mais velhas da parentela, as mulheres reúnem um conjunto próprio de conhecimentos e ocupam posição de reconhecido destaque no parentesco guarani, habilitando-as para levantar pessoas e levantar terras no contexto de recuperação de territórios, em curso desde os anos 1970, e conhecido entre os Guarani e Kaiowa por “retomadas”. Empreendidas como um fazer político guarani e kaiowa, as retomadas exprimem o sentido de uma promessa quanto ao retorno de seres e divindades ao território (tekoha), em consequência direta da recuperação da terra, restaurando os saberes guardados e as sementes armazenadas por mulheres durante o processo histórico de retirada forçada dos territórios tradicionais e confinamento socioespacial vivenciado por esses indígenas
Polymerization Kinetics and Polymer Characterization by Fluorogenic Atom Transfer Radical Polymerization (ATRP)
No full textControlling reaction kinetics with precision is vital for tailoring polymer properties such as molecular weight and dispersity; thus, reactions which are able to control and optimize for these characteristics are becoming increasingly important. Current methods that are able to reliably and carefully monitor polymerizations involve highly specialized, costly, and low-throughput instrumentation which all sacrifice the ability to monitor reaction kinetics in real-time. As an alternative to these complex and expensive setups, fluorogenic atom transfer radical polymerization (fluorogenic ATRP) is explored as a simple and accessible method for the direct, in situ, monitoring of polymerization kinetics and for the purposes of polymer molecular weight characterization.
The Cooley Group has previously demonstrated that a fluorogenic monomer probe, anthracene methacrylamide (AnMA), will yield a fluorescent polymer upon co-polymerization, even at low concentrations of this monomer. The trace incorporation of anthracene methacrylamide into a variety of preexisting reactions allows for simple fluorescence measurements to act as a non-invasive technique to monitor the degree of polymerization and polymer molecular weight. This work details the testing and efficacy of this approach through reactions which copolymerize anthracene methacrylamide (and other fluorogenic monomers) into a variety of both established and emerging ATRP reactions to understand and define parameters for the relationship between observed polymer fluorescence and polymer characteristics. Additional work is also being done to characterize the polymers formed from these reactions, and a proof-of-concept surface-initiated polymerization application has been developed and is currently the subject of ongoing experimentation