Over the past 500 years, North America has been the site of ongoing mixing of Native Americans, European settlers, and Africans (brought largely by the trans-Atlantic slave trade), shaping the early history of what became the United States. We studied the genetic ancestry of 5,269 self-described African Americans, 8,663 Latinos, and 148,789 European Americans who are 23andMe customers and show that the legacy of these historical interactions is visible in the genetic ancestry of present-day Americans. We document pervasive mixed ancestry and asymmetrical male and female ancestry contributions in all groups studied. We show that regional ancestry differences reflect historical events, such as early Spanish colonization, waves of immigration from many regions of Europe, and forced relocation of Native Americans within the US. This study sheds light on the fine-scale differences in ancestry within and across the United States and informs our understanding of the relationship between racial and ethnic identities and genetic ancestry.
Akshit R. Suthar, Alan R. Biggs, James T. Anderson
Despite increasing conservation efforts for shorebirds, there are widespread declines in many shorebird species in North America. Climate change is causing significant shorebird range shifts and population declines. This study investigates the relationship between meteorological variability and shorebird population dynamics over ten years (2014–2023) at Fish Haul Beach, Hilton Head Island, South Carolina, USA. Shorebirds, reliant on specific habitats for breeding and foraging, are increasingly vulnerable to climate-driven changes, including shifts in temperature, precipitation, and wind speed. Using Generalized Additive Models with Poisson distribution, we analyzed species-specific count data for 12 shorebird species in relation to annual meteorological variables. Additionally, the Mann–Kendall test and Sen’s slope were employed to assess decadal trends in population counts. The results reveal significant declines in Black-bellied Plover (<i>Pluvialis squatarola</i>), Marbled Godwit (<i>Limosa fedoa</i>), and Willet (<i>Tringa semipalmata</i>). In contrast, Semipalmated Plover (<i>Charadrius semipalmatus</i>) and Piping Plover (<i>Charadrius melodus</i>) showed increasing trends, indicating potential habitat benefits or conservation success. Temperature emerged as a key driver affecting the abundance of several species, while precipitation and wind speed also played crucial roles in shaping population dynamics. Our findings underscore the sensitivity of shorebird populations to weather fluctuations, emphasizing the need for integrating meteorological variability into management strategies to ensure shorebird conservation. This study provides critical insights into the impacts of meteorological variables on migratory shorebird populations along the Atlantic Flyway. It highlights the importance of maintaining healthy coastal ecosystems in South Carolina.
L. W. Cavalheiro, A. Antunes de Souza Santos, C. Bernhardt Fialho
Cambios longitudinales y ontogénicos en las pautas de alimentación de una especie insectívora de la familia Crenuchidae en arroyos del sur del Brasil
El género Characidium es el más rico en especies de la familia Crenuchidae y la subfamilia Characidiinae. Characidium pterostictum reviste una inmensa importancia debido a su amplia distribución en América del Sur, en especial en los sistemas hidrográficos del río Uruguay. El objetivo del presente estudio es describir la biología alimentaria de Characidium pterostictum en los arroyos de la cuenca del río Ijuí (sistema del río Uruguay) en el sur del Brasil, así como determinar las posibles variaciones espaciales y ontogénicas de su dieta. Se recogieron muestras en tres afluentes del río Ijuí. Se identificaron y cuantificaron los alimentos utilizando el método volumétrico y la frecuencia de presencia. Characidium pterostictum se caracterizó como un pez insectívoro, una especialización que ya se había observado en la subfamilia Characidiinae. Existe una ligera diferencia en las pautas de alimentación en función de las variaciones en la longitud estándar de los individuos y los sitios de muestreo. El análisis ontogenético demostró que Characidium pterostictum amplía el espectro alimentario a medida que se va desarrollando. El consumo de alimentos autóctonos (restos de insectos, efemerópteros, tricópteros y quironómidos) como principal componente de la dieta indica que esta especie de pez necesita la conservación intensiva de los cursos de agua en los que vive.
Reka Borka Balas, Lorena Elena Meliț, Cristina Oana Mărginean
<i>Helicobacter pylori</i> is usually acquired during childhood. The reports from the last two decades pointed out a decrease in <i>H. pylori</i> prevalence across geographical areas worldwide compared to previously reported data. Most of the studies performed in America found an overall <i>H. pylori</i> infection prevalence of approximately 50%. The most important risk factors in America include being male, poor adherence or difficult access to treatment, and the lack of in-home water service. Despite the descending trend in prevalence worldwide, the overall prevalence in Africa remains very high (70%). Nevertheless, the prevalence of <i>H. pylori</i> in children without gastrointestinal who underwent screening was reported to be only 14.2%. The main risk factors in Africa are having a traditional pit or no toilet, poverty, birth order, source of drinking water, or being a farmer. Asia seems to have the widest variations in terms of <i>H. pylori</i> prevalence. Several risk factors were reported in Asia to be associated with this infection, such as lower income and educational level, house crowding, rural residence, ethnicity, the use of tanks as water supplies, alcohol drinking, active smoking, eating spicy food or raw uncooked vegetables, poor living conditions and sanitation. The overall prevalence of <i>H. pylori</i> infection in European children is almost 25%. Portugal has the highest prevalence of all European countries at 66.2% in children 13 years of age. The risk factors in European individuals consist of living in rural areas, eating unwashed fruits and vegetables, not washing hands after school, low parental education and unemployment, and short education duration. Further studies are required to identify the precise mechanisms involved in the discrepancies of <i>H. pylori</i> prevalence worldwide.
La conferencia de Medellín es el fruto maduro del Concilio Vaticano II en la iglesia de América Latina. Centrado en la confesión de fe en Jesucristo. Señor de la Historia, ha sido uno de los mejores análisis de la realidad latinoamericana a la luz de la fe, de la esperanza y con miras a la caridad operante. Quienes fueron protagonistas de esta asamblea no lo hicieron encerrados en su ego de líderes religiosos de la iglesia, sino que se dejaron permear de la acción de Espíritu al abrir sus ojos a la realidad de los pobres y a la voz de los laicos y personas que. También movidos por la fe, dieron sus aportes. Este artículo nos introduce en el significado de la Conferencia Episcopal de Medellín 1968, por uno de sus testigos históricos, dado que ella nos puso la cara a la necesidad de reafirmar los principios vinculados a la salvación histórica, confirmar valores, comprometernos con la dignidad del hombre, con la búsqueda del bien común, con la lucha contra la pobreza en el incondicional amor al prójimo que nos lleva a desechar la violencia porque “ni el oído ni la violencia son la fuerza de nuestra caridad” (Pablo VI) para que la paz reine y circule libremente la vida como señal de esperanza.
Las infecciones del sistema nervioso central por amebas son una entidad poco frecuente, sin embargo, se caracterizan por una extrema virulencia y un pronóstico devastador. Naegleria fowleri es la ameba responsable de producir meningoencefalitis amebiana primaria. Los géneros Acanthamoeba y Balamuthia, otro tipo de amebas, son los agentes etiológicos de la encefalitis granulomatosa amebiana, que pese a tener un curso más lento y una menor virulencia presentan una letalidad casi tan elevada como la Naegleria fowleri.Debido a los síntomas inespecíficos, estas infecciones suelen ser simular cuadros bacterianos, virales u otros no infecciosos. La alta sospecha diagnóstica sobre todo en pacientes con antecedente de exposición reciente con aguas contaminadas, resulta fundamental a la hora de abordar estos casos. Se han utilizado diferentes esquemas de tratamiento; no obstante, no se ha establecido una terapia eficaz y el desenlace sigue siendo fatal en la gran mayoría de los casos.
”The Miss Austen of Sweden”. Fredrika Bremer in the 1840s America and Historiographical Revaluation
How did Fredrika Bremer’s (1801–1865) depictions of Scandinavian family life become so immensely popular in the United States in the 1840s, and what did this transatlantic success have to do with gender, translation, media history, and nation building? In an attempt to trace the prerequisites for the intense yet rather short lived American ”Bremer-mania”, this article focuses on the period 1842 to 1844 – a task greatly facilitated by the last decades’ substantial
digitizing of book collections and historical press material. The investigation shows that Bremer’s breakthrough occurred in a very specific situation in American social-, cultural-, and media history, and that her novels filled certain needs in the ongoing postcolonial struggle to foil British cultural hegemony. In this process, Bremer’s depictions of young women fighting for freedom offered a transfer identity, a position that for obvious reasons was provisional and temporary. As publishers started to invest in local writers, the boom for Scandinavian fiction soon decreased, and has left few traces in the history of the 19th century American novel. Fredrika Bremer’s American career is yet another example of how translated literature and international dissemination is inadequately reflected in national literary historiography. However, considering the last decades’ growing focus on transcultural dissemination, it is eligible that future research pays more attention to the diversity of literary flows and circulations.
Katrina Sinclair, Andrea Rawluk, Saideepa Kumar
et al.
Resilience thinking appears to offer a holistic approach that can be used by social researchers to interpret past and contemporary conditions and identify possible futures for social-ecological systems (SES). Resilience thinking is shaping contemporary environmental policy and its implementation in Australia, Europe, and North America. At the same time, social researchers have raised concerns about the limitations of resilience thinking, particularly in its handling of human agency, power relationships, social thresholds, and the social construction of SES definitions. We argue for a reflexive turn in resilience thinking as a way to address these concerns. We draw on lessons from three Australian case studies where a reflexive application of resilience thinking generated insights for research and practice. We propose six areas for reflexive inquiry: (1) focal scale and level, (2) SES definition, (3) narratives of change, (4) processes of knowledge production, (5) social transition trajectories, and ( 6) social thresholds. In so doing, the assumptions of resilience thinking are politicized and problematized, which improves its theoretical analytical utility, and in practice generates new insights into social processes. Reflexivity offers opportunity for greater cross-disciplinary dialogue between resilience thinking and the social sciences, while allowing methodologies with differing ontologies and epistemologies to be applied in a complementary manner.
Maureen Laroche, Jean-Michel Berenger, Oleg Mediannikov
et al.
BACKGROUND:Among the Reduviidae family, triatomines are giant blood-sucking bugs. They are well known in Central and South America where they transmit Trypanosoma cruzi to mammals, including humans, through their feces. This parasitic protozoan is the causative agent of Chagas disease, a major public health issue in endemic areas. Because of the medical and economic impact of Chagas disease, the presence of other arthropod-borne pathogens in triatomines was rarely investigated. METHODOLOGY/PRINCIPAL FINDINGS:In this study, seven triatomines species involved in the transmission of T. cruzi were molecularly screened for the presence of known pathogens generally associated with arthropods, such as Rickettsia, Bartonella, Anaplasmataceae, Borrelia species and Coxiella burnetii. Of all included triatomine species, only Eratyrus mucronatus specimens tested positive for Bartonella species for 56% of tested samples. A new genotype of Bartonella spp. was detected in 13/23 Eratyrus mucronatus specimens, an important vector of T. cruzi to humans. This bacterium was further characterized by sequencing fragments of the ftsZ, gltA and rpoB genes. Depending on the targeted gene, this agent shares 84% to 91% of identity with B. bacilliformis, the agent of Carrion's disease, a deadly sandfly-borne infectious disease endemic in South America. It is also closely related to animal pathogens such as B. bovis and B. chomelii. CONCLUSIONS:As E. mucronatus is an invasive species that occasionally feeds on humans, the presence of potentially pathogenic Bartonella-infected bugs could present another risk for human health, along with the T. cruzi issue.
Arctic medicine. Tropical medicine, Public aspects of medicine
In 1764, the Bourbon State initiated the reform to the overseas mail system between Spain and America that tried to generate a regularity in the service, to diversify the routes and to promote the incorporation of the overland mail into the State. This resulted in a series of institutional changes to take control of the written communication channels within the empire. This, the new postal regulations fell on several colonial officials (“administradores, subalternos y tenientes de correo”) who had the duty to dispatch of letters at regional, vice royal and imperial levels. The present article seeks to understand the experience and practices generated by the expansion of the absolutist state illustrated on the communicative dimension of the empire in the Colonial Chilean government. From the analysis of the files of the Administradora General de Correos de Chile – both in the Archivo Nacional Histórico de Chile and in Archivo de Indias in Seville – we understand that these subordinates allowed, through negotiations and conflicts, the integration and political communication of the territory from Santiago to the internal provinces, and from these to Madrid. What, in short, installed them as agents of change within the colonial government.
Frances C Moore, Uris Lantz C Baldos, Thomas Hertel
A large number of studies have been published examining the implications of climate change for agricultural productivity that, broadly speaking, can be divided into process-based modeling and statistical approaches. Despite a general perception that results from these methods differ substantially, there have been few direct comparisons. Here we use a data-base of yield impact studies compiled for the IPCC Fifth Assessment Report (Porter et al 2014 ) to systematically compare results from process-based and empirical studies. Controlling for differences in representation of CO _2 fertilization between the two methods, we find little evidence for differences in the yield response to warming. The magnitude of CO _2 fertilization is instead a much larger source of uncertainty. Based on this set of impact results, we find a very limited potential for on-farm adaptation to reduce yield impacts. We use the Global Trade Analysis Project (GTAP) global economic model to estimate welfare consequences of yield changes and find negligible welfare changes for warming of 1 °C–2 °C if CO _2 fertilization is included and large negative effects on welfare without CO _2 . Uncertainty bounds on welfare changes are highly asymmetric, showing substantial probability of large declines in welfare for warming of 2 °C–3 °C even including the CO _2 fertilization effect.
Yoshimitsu Chikamoto, Axel Timmermann, Matthew J. Widlansky
et al.
Abstract Past severe droughts over North America have led to massive water shortages and increases in wildfire frequency. Triggering sources for multi-year droughts in this region include randomly occurring atmospheric blocking patterns, ocean impacts on atmospheric circulation, and climate’s response to anthropogenic radiative forcings. A combination of these sources translates into a difficulty to predict the onset and length of such droughts on multi-year timescales. Here we present results from a new multi-year dynamical prediction system that exhibits a high degree of skill in forecasting wildfire probabilities and drought for 10–23 and 10–45 months lead time, which extends far beyond the current seasonal prediction activities for southwestern North America. Using a state-of-the-art earth system model along with 3-dimensional ocean data assimilation and by prescribing the external radiative forcings, this system simulates the observed low-frequency variability of precipitation, soil water, and wildfire probabilities in close agreement with observational records and reanalysis data. The underlying source of multi-year predictability can be traced back to variations of the Atlantic/Pacific sea surface temperature gradient, external radiative forcings, and the low-pass filtering characteristics of soils.