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Construyendo resiliencia ante eventos extremos en ciudades: el caso de la ciudad de La Paz, México
No full textLa municipalidad de La Paz (estado de Baja California Sur, México; Figura 1) tiene una población de 292,241 habitantes y recibe anualmente más de 500,000 visitantes por trabajo, negocios, educación, salud y turismo. Del total de la población de La Paz, 93.6% se concentra en áreas de costa, mientras que 4.3% y 2% se en localiza en el valle y las montañas, respectivamente (Ivanova y Gamez, 2012). La ciudad de La Paz es la capital del estado de Baja California Sur por lo que concentra la mayor parte de los servicios de gobierno, educación y salud. El área de la ciudad presenta una tendencia de expansión continua al 2030, tal y como se presenta en la Figura 2.
Este caso de estudio se centra en:
1) Analizar la vulnerabilidad de La Paz ante eventos extremos por medio de una evaluación de riesgos múltiples; 2) Identificar las capacidades institucionales para mejorar la resiliencia y la capacidad de respuesta; 3) Presentar algunos retos futuros
The Evolution of the Antarctic Ice Sheet Over the Plio-Pleistocene Inferred from Scotia Sea Sediments
No full textOur ability to predict future global sea level rise is limited by our understanding of the fundamental ice dynamics that govern ice sheet retreat and collapse. The Antarctic Ice Sheet holds the vast majority of potential sea level rise, and understanding the primary controls of retreat is crucial for understanding the evolution of the ice sheet and identifying key parameters to monitor for the future. Antarctica has extensive marine-based margins, characterized by large, fringing ice shelves. Icebergs calve off the margins of these ice shelves and, with them, they carry and deposit poorly- sorted terrestrial iceberg-rafted debris (IRD) into ocean sediments. Therefore, paleoceanographic records of IRD allow us to quantify the timing and provenance of major iceberg discharge events in the past.
In this dissertation, I employed a range of quantitative, sedimentological, and geochronological techniques to study the history of Antarctic IRD over the late Pliocene and Pleistocene. The key problems that I aim to address in this dissertation are: what are the main controls on the stability of the Antarctic Ice Sheet in the past, and what are the major factors that drove iceberg discharge and inland retreat of the ice sheet margins in the past? To answer these questions, I have focused on deep-sea sediment drill cores collected during the International Ocean Discovery Program (IODP) Expedition 382 in the Scotia Sea, a region in the Southern Ocean, where the vast majority of Antarctic icebergs pass through.
In Chapter 1, I developed a novel artificial intelligence (AI) algorithm that was trained to identify iceberg rafted debris in X-ray images of sediment drill cores. By applying this new AI model to hundreds of meters of cores, I created a 3.3 million-year (Myr) record of Antarctic iceberg discharge. I observe an increase in the flux of IRD just after 1.8 million years ago (Ma), which likely represents an expansion of the Antarctic Ice Sheet from a primarily terrestrial-based to a marine-based ice sheet after this time.
In Chapter 2, I focus on an increase in the flux of IRD after 0.43 Ma, which is aligned with the Mid-Brunhes Event. I suggest that increased iceberg discharge is related to the enhanced retreat of marine-based margins at glacial terminations, which is linked to the southward shift in the Southern Hemisphere Westerlies and the Antarctic Circumpolar Current, driving increased basal melt and iceberg calving. I also suggest that the Northern Hemisphere-triggered thermal bipolar seesaw could be an additional factor in driving Antarctic iceberg discharge during both glacial inception and glacial terminations.
Finally, in Chapter 3, I created a high-resolution 1.2 Myr record of IRD discharge using physical samples spanning the early to mid-Pleistocene, and I considered the provenance and pacing of iceberg discharge throughout this period. I find that after 1.7 Ma, the dominant provenance of IRD is from the West Antarctic Ice Sheet. After this time, iceberg discharge is primarily driven by the glacial-interglacial variability of the Antarctic Circumpolar Current and modulated by the variance in summer insolation. Taken collectively, the chapters of this dissertation suggest that the early Pleistocene expansion of the marine-based margins of the Antarctic Ice Sheet established an inherently unstable system, in which perturbations in ocean and atmospheric circulation could trigger significant iceberg discharge events throughout the Pleistocene
An accurate solar axions ray-tracing response of BabyIAXO
No full textAbstract BabyIAXO is the intermediate stage of the International Axion Observatory (IAXO) to be hosted at DESY. Its primary goal is the detection of solar axions following the axion helioscope technique. Axions are converted into photons in a large magnet that is pointing to the sun. The resulting X-rays are focused by appropriate X-ray optics and detected by sensitive low-background detectors placed at the focal spot.
The aim of this article is to provide an accurate quantitative description of the different components (such as the magnet, optics, and X-ray detectors) involved in the detection of axions. Our efforts have focused on developing robust and integrated software tools to model these helioscope components, enabling future assessments of modifications or upgrades to any part of the IAXO axion helioscope and evaluating the potential impact on the experiment’s sensitivity.
In this manuscript, we demonstrate the application of these tools by presenting a precise signal calculation and response analysis of BabyIAXO’s sensitivity to the axion-photon coupling. Though focusing on the Primakoff solar flux component, our virtual helioscope model can be used to test different production mechanisms, allowing for direct comparisons within a unified framework
Girls’ Mathematical Mindsets And Gendered Mathematical Beliefs In An All-girls Classroom
Get PDFOver recent decades, education stakeholders have raised significant concerns regarding theunderrepresentation of females in science-related professions and academic programs, particularly in mathematics. Existing research in this domain highlights that the social transmission of unfavorable beliefs about mathematics —such as mathematical anxiety, gendered mathematical beliefs, and beliefs about mathematical intelligence — may contribute to gender inequality and a gender gap in mathematics-related majors and occupations.
This study was undertaken to investigate the variables influencing the mathematical mindsets and gendered mathematical beliefs of female students within an all-girls educational setting. The research questions were formulated by the researcher with the purpose of examining and exploring the variables that influence the mathematical mindsets and gendered mathematical beliefs of female students in an all-girls environment. By doing so, further insights can be gained into the means of encouraging and enhancing the mathematical mindsets and gendered mathematical beliefs of female students.
The conceptual framework for this study is grounded in growth mindset theory. Data were collected through a combination of interviews, surveys, and classroom observations, and analyzed using a mixed-methods approach, incorporating both quantitative and qualitative methodologies. The specific methodologies employed include (a) qualitative descriptive analysis, (b) Chi-Squared tests, (c) the Mann-Whitney U test, and (d) thematic analysis.
Based on the results of this study, the suggested recommendations aim to foster collaboration among students, educators, and policymakers to build supportive environments that nurture growth-oriented mathematical mindsets and challenge pervasive gendered mathematical beliefs. By addressing these constructs, suggested strategies can be used to empower students, particularly girls, to excel in mathematics and confidently pursue STEM-related careers. Implementing the study's findings and recommendations can promote gender equity in education, ensuring that all learners, particularly females, have the opportunity to achieve their full potential in mathematics and beyond
Food Systems Countdown Initiative: Asia Baseline Report
No full textFood system transformation is central to meeting the Sustainable Development Goals (SDGs) by their 2030 deadline as well as to meeting the targets and commitments established in the three Rio Conventions on climate change (UNFCCC), the Convention on Biological Diversity (UNCBD), and the UN Convention to Combat Desertification (UNCCD). Meeting these goals is possible, but decisive and deliberate decisions are required to set countries, companies, and consumers on a more sustainable, healthy, equitable, and resilient path. Choosing those right actions requires rigorous evidence. This policy brief provides the Asia region with a snapshot of the current state of their food system, establishing a baseline understanding of key challenges and strengths across different food system dimensions
(Un)Homely Encounters The Poetics and Politics of Heimat Between 19th Century Orientalism and Contemporary Literatures of Migration
No full textThe dissertation engages the concept of Heimat, home(land), from new angles. Over its long and fraught history, this (to many scholars) “quintessentially German” concept has prominently acquired autochthonous, politically regressive significations. The present study, however, traces how these static and exclusionary implications shift in the deployments of Heimat by German Orientalists, German-Jewish émigrés in Istanbul, and contemporary writers of migration.
Its scope, therefore, cuts across periods, locales, and genres. In comparative and interdisciplinary configurations, the dissertation investigates new articulations of Heimat in Friedrich Schlegel, Goethe, Leo Spitzer, Meral Kureyshi, Mehrnousch Zaeri-Esfahani, and Fatih Akın. In its reformulation of Heimat from these readings, it demonstrates the indispensable role of cross-cultural engagements and the integral function of the so-called East in constructing Heimat and German identities.
In this way, the project at hand re-envisions the lingual and cultural heritages of the field to flesh out a complex nexus of multilingual, transcultural, and intergenre literary engagements while rethinking paradigms from postcolonial, trauma, and diaspora studies, among others
Estimating the cost of and willingness to pay for providing the dapivirine ring for HIV prevention in Kenya
Get PDFBackground
As Kenya prepared to introduce the PrEP ring (a long-acting product used by women for HIV prevention), the need to understand the resources required became increasingly important. The aim of this study was to determine the costs and preferences of potential ring clients by conducting a normative cost analysis and a contingent valuation study (In the context of willingness to pay literature, “preference” is used to refer to an interest in a service or product with specified benefits).
Methods
The study incorporates two parts: 1) a normative costing to estimate potential costs of providing the PrEP ring and 2) a willingness to use/pay assessment to evaluate client preference for the PrEP ring. Oral PrEP program managers from 12 facilities were interviewed to assess the direct and indirect resources required to deliver PrEP ring services. 539 women were interviewed (including both younger and older women, as well as female sex workers) using a questionnaire to assess the strength of the expressed interest in PrEP ring use, as reflected by their contingent valuation of the product. Women were presented with payment cards from which they selected the most they would be willing to pay. The primary outcomes of the study were: 1) the annual cost of PrEP ring use and 2) the average willingness to pay for the PrEP ring. Women in the willingness to pay component were selected, using a convenience sample, with approximately equal numbers of oral PrEP users and clients from other health services.
Results
The cost to provide a full year of PrEP ring was US156) of that cost was attributed to the PrEP rings. Of the respondents, 78% indicated some interest in using the PrEP ring; among those interested, 83% indicated some willingness to pay for it. Single women and women currently using oral PrEP expressed more interest in using the ring than women who were married or were not currently oral PrEP users. The median willingness to pay per visit was US2 per month for the PrEP ring. Since the demand for the PrEP ring appears to be higher among current oral PrEP users compared to non-users, women who have initiated oral PrEP but who are unable or unwilling to continue may be good candidates for PrEP ring use. The annual willingness to pay for the PrEP ring (US206 per year), which suggests that attempts to fully recover costs would present a significant barrier for Kenyan women and would minimize societal benefits
A National Cinema in Search of a Nation: Media Culture, Spectatorship, and Colonial (After)Lives of Manchuria, 1900s-1940s
No full textThis dissertation investigates the media and cultural history of cinema in Manchuria (today’s northeast China) from the 1900s through the 1940s. Situated where China, Russia, Korea, and Mongolia meet, Manchuria was a region marked by ethnic diversity and political conflict throughout during the first half of the twentieth century.
Between 1932 and 1945, Manchuria was also known as Manchukuo, Japan’s multi-ethnic client state. Existing literature that has directed attention to Manchuria has been preoccupied with the Manchukuo period, with a focus on the Manchuria Film Association (Chinese: Manying; Japanese: Man’ei, 1937-1945) and its efforts to construct a national cinema for this artificially engineered nation. Building on previous scholarship while moving beyond the timeframe of Manchukuo and the bounded region of East Asia, this dissertation argues for a rewriting of the history of cinema in Manchuria from translocal, transcolonial, and media archaeological perspectives.
By situating cinema in Manchuria within a broader regional and global media environment, this dissertation explores what cinema really meant to Manchuria as a locality, and how cinema was transformed by, and in turn shaped, the everyday lives of Manchuria’s multi-ethnic populations beyond its role as a vehicle for imperial propaganda.Drawing on multi-lingual archival research conducted in Japan and China, the dissertation unfolds in three parts. Starting with the uneasy relationship between cinema and ethno-nationality in Manchuria and opening onto global questions of race and imperialism, the dissertation situates the filmic practices in Manchuria not only within the colonial encounter between China and Japan but also in the broader histories of empire and modernity.
The first portion explores the construction of local film culture in early twentieth-century Dalian and Harbin, highlighting the dynamic interplay of Chinese, Japanese, and Russian cultural encounters. It then moves on to the Manchukuo period and examines how melodrama films produced by Man’ei played into transregional knowledge production about race, ethnicity, and nation among Japan, China, and the United States. Viewing Manchuria as a locality while reconsidering film as event and encounter, the second portion uncovers cinema’s embeddedness in the everyday cultural life of the region through case studies of colonial expositions, public health campaigns, and mobile screenings.
By probing cinema’s symbiosis with other media technologies of visualization and nation-building, I further highlight the shifting cultural logics and technological dynamics underlying the mutual constitution of Manchuria as a locality and the medium itself. The final portion critically reflects on the aporia of Manchuria’s film historiography and its contested legacy in postwar Communist China. Centering on Sakane Tazuko, Japan’s first female director with a career spanning prewar Japan, colonial Manchuria, and communist China, the portion offers a lens for rewriting film history through feminist and queer perspectives.
The dissertation unfolds across five chapters, each examining cinema in Manchuria from a distinct angle—as a translocal practice, a carrier of global racial discourses, a nodal point in a cross-media network, a site-specific and embodied experience, and gendered articulation. By challenging the East/West and imperial/national dichotomies, the dissertation not only works towards a more expansive reflection on the cinematic (de)construction of nation and race and ethnicity in a global context, but also offers a deeper understanding of cinema’s cross-cultural and cross-media articulation of colonial modernity in the larger transformation of this contested region
A Case for Libraries' Survival in the Internet Age: Mass Digitization of Literary Works and the Legality of Controlled Digital Lending
No full textIn the United States, copyright law rests upon a delicate balancing act. Our system aims to maximize both incentives for right holders to create and public access to creative works under a constitutional mandate to “[p]romote the Progress of Science and useful Arts.” Forces of technology and globalization have compounded the complexities of striking that balance, making it far easier for a physical literary work to be scanned, digitized, and shared around the world—often without the author’s express permission. In turn, the digitization of creative works offers widespread benefits for the maximization of public accessibility: A work can reach the hands of countless students and scholars who would not otherwise have the funds, resources, or accommodations to read it
