Indagación llevada a cabo con docentes de primaria en formación sobre temas básicos de Astronomía

Trabajamos en el diagnóstico situacional de los docentes de escuela primaria en formación, con el propósito de desarrollar herramientas didácticas que contribuyan a mejorar su educación formal. Presentamos el material con el que llevamos a cabo una indagación sobre los conocimientos generales en temas básicos de astronomía de los futuros docentes. Se trata de un cuestionario escrito y abierto -aunque también se incluyen algunas preguntas cerradas- sobre un grupo selecto pero representativo de nociones básicas de astronomía. En este trabajo se plantean y discuten los resultados de dos pruebas piloto, suministradas a 30 individuos, y se comentan los cambios realizados para el diseño del instrumento final, que fue implementado en otros 51 alumnos normalistas. Un análisis cualitativo de las respuestas reveló varias concepciones alternativas conocidas en la literatura (e.g., la teoría del eclipse, para explicar las fases lunares), y otras nuevas. Los resultados muestran una notoria dificultad en la explicación del movimiento de la Luna y de sus fases. Los individuos encuestados también encontraron serias dificultades para explicar un par de elementos astronómicos que integran el lenguaje cotidiano, como ser a qué se llama una estrella fugaz y cuál es la verdadera identidad del lucero. Entre las respuestas ofrecidas para explicar las estaciones del año, se encontró una causalidad singular (que, creemos, no fue aun suficientemente estudiada en la literatura específica): muchos encuestados en lugar de proponer un modelo explicativo -una causa: por ejemplo, la inclinación del eje terrestre- que justificara un determinado fenómeno -el efecto: las diferentes estaciones del año-, hacían uso de otro fenómeno/efecto, en este caso en relación al clima, fenómeno que, como sabemos, posee una fuerte componente astronómica. Presentamos aquí los resultados completos para las pruebas piloto y para la prueba final, y concluimos elaborando algunas conclusiones.Fil: Gangui, Alejandro. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; ArgentinaFil: Iglesias, Maria C.. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Formación E Investigación En Enseñanza de Las Ciencias; ArgentinaFil: Quinteros, Cynthia Paula. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Formación E Investigación En Enseñanza de Las Ciencias; Argentin

El movimiento de las sombras: Una propuesta de trabajo para la escuela secundaria

Numerosas investigaciones extranjeras y algunas locales ponen de manifiesto las dificultades que encuentran los alumnos de la escuela media para comprender algunos fenómenos astronómicos. Ello nos llevó a reflexionar sobre el estado de la enseñanza y el aprendizaje de esos temas. Entre las dificultades, podemos mencionar la de reconocer los cambios en los aspectos observables del movimiento del Sol: duración del día, lugares y momentos de la salida y puesta del Sol, su altura máxima en el cielo, etcétera.Además, muy pocos estudiantes son capaces de identificar los momentos singulares del año (los equinoccios y los solsticios) y las regularidades que acaecen en torno a ellos, lo cual va asociado con una visión distorsionada de cómo se producen los cambios astronómicos a lo largo del año. Tampoco suelen reconocer la existencia de representaciones o modelos alternativos que puedan dar cuenta de algunas observaciones, ni se hace uso operativo en los colegios de las hipótesis de los modelos para explicar observaciones conocidas. Como regla general, los alumnos no utilizan hipótesis para explicar fenómenos relacionados, aun si se les pregunta explícitamente por un hecho que no pueden justificar.Formadores e investigadores en la didáctica de la astronomía señalan que la recurrencia de las llamadas ideas previas se prolonga más allá de la escuela secundaria y afecta también a estudiantes de magisterio y a profesores en actividad. Frente a estas cuestiones, cabe preguntarse qué podemos hacer los docentes universitarios e investigadores para superar los obstáculos que impiden o dificultan la construcción del conocimiento cientifico. Como plantea, por ejemplo, Martínez Sebastià, la enseñanza de la astronomía no puede limitarse a saber que la Tierra es una esfera que gira sobre sí misma y alrededor del Sol: también debe poder contribuir a explicar los fenómenos astronómicos mediante dichas hipótesis.Creemos que un buen camino para paliar estas deficiencias es la enseñanza-aprendizaje por investigación, que supone enfrentar a los alumnos con diversas preguntas o situaciones problemáticas. De la misma forma que en la ciencia los conocimientos se elaboran en respuesta a preguntas, este enfoque considera que una enseñanza basada en situaciones problemáticas favorece un aprendizaje significativo.A la luz de lo dicho, presentamos aquí una propuesta de trabajo para ser llevada al aula por los docentes. Tiene una pregunta o problema como hilo conductor, a modo de guía, que da sentido a la secuencia presentada. La pregunta es: ¿cómo utilizar las sombras para construir un reloj que marque las horas? Se espera que, al intentar responder, los alumnos aborden algunos temas de astronomía de manera progresiva y secuenciada, partiendo de sus conocimientos previos y contrastando los temas estudiados con ellos. Al finalizar, podrán construir un reloj de Sol y explicar su funcionamiento.Fil: Gangui, Alejandro. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; ArgentinaFil: Iglesias, Maria C.. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Formación E Investigación En Enseñanza de Las Ciencias; ArgentinaFil: Quinteros, Cynthia Paula. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Formación E Investigación En Enseñanza de Las Ciencias; Argentin

Impact of CYP2C:TG Haplotype on CYP2C19 substrates clearance in vivo, protein content, and in vitro activity

A novel haplotype composed of two non-coding variants, CYP2C18 NM_000772.3:c.*31T (rs2860840) and NM_000772.2:c.819+2182G (rs11188059), referred to as “CYP2C:TG,” was recently associated with ultrarapid metabolism of various CYP2C19 substrates. As the underlying mechanism and clinical relevance of this effect remain uncertain, we analyzed existing in vivo and in vitro data to determine the magnitude of the CYP2C:TG haplotype effect. We assessed variability in pharmacokinetics of CYP2C19 substrates, including citalopram, sertraline, voriconazole, omeprazole, pantoprazole, and rabeprazole in 222 healthy volunteers receiving one of these six drugs. We also determined its impact on CYP2C8, CYP2C9, CYP2C18, and CYP2C19 protein abundance in 135 human liver tissue samples, and on CYP2C18/CYP2C19 activity in vitro using N-desmethyl atomoxetine formation. No effects were observed according to CYP2C:TG haplotype or to CYP2C19*1+TG alleles (i.e., CYP2C19 alleles containing the CYP2C:TG haplotype). In contrast, CYP2C19 intermediate (e.g., CYP2C19*1/*2) and poor metabolizers (e.g., CYP2C19*2/*2) showed significantly higher exposure in vivo, lower CYP2C19 protein abundance in human liver microsomes, and lower activity in vitro compared with normal, rapid (i.e., CYP2C19*1/*17), and ultrarapid metabolizers (i.e., CYP2C19*17/*17). Moreover, a tendency toward lower exposure was observed in ultrarapid metabolizers compared with rapid metabolizers and normal metabolizers. Furthermore, when the CYP2C19*17 allele was present, CYP2C18 protein abundance was increased suggesting that genetic variation in CYP2C19 may be relevant to the overall metabolism of certain drugs by regulating not only its expression levels, but also those of CYP2C18. Considering all available data, we conclude that there is insufficient evidence supporting clinical CYP2C:TG testing to inform drug therapyP.S.-C. is financed by Universidad Autónoma de Madrid (FPIUAM, 2021). P.Z. is financed by Universidad Autónoma de Madrid, Margarita Salas contract, grants for the requalification of the Spanish university system. A.R.-L. and E.G.-I. contracts are financed by Programa Investigo (NextGenerationEU funds of the Recovery and Resilience Facility), fellowship numbers 2022-C23.I01.P03. S0020–0000031 and 09-PIN1-00015.6/2022. Human liver tissue samples were obtained through the Liver Tissue Cell Distribution System, Minneapolis, MN, and Pittsburgh, PA, which was funded by NIH Contract #HHSN276201200017C. The proteomics part of the work was supported by Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH) Grant R01.HD08129

Desing and Validation of a Light Inference System to Support Embedded Context Reasoning

Embedded context management in resource-constrained devices (e.g. mobile phones, autonomous sensors or smart objects) imposes special requirements in terms of lightness for data modelling and reasoning. In this paper, we explore the state-of-the-art on data representation and reasoning tools for embedded mobile reasoning and propose a light inference system (LIS) aiming at simplifying embedded inference processes offering a set of functionalities to avoid redundancy in context management operations. The system is part of a service-oriented mobile software framework, conceived to facilitate the creation of context-aware applications—it decouples sensor data acquisition and context processing from the application logic. LIS, composed of several modules, encapsulates existing lightweight tools for ontology data management and rule-based reasoning, and it is ready to run on Java-enabled handheld devices. Data management and reasoning processes are designed to handle a general ontology that enables communication among framework components. Both the applications running on top of the framework and the framework components themselves can configure the rule and query sets in order to retrieve the information they need from LIS. In order to test LIS features in a real application scenario, an ‘Activity Monitor’ has been designed and implemented: a personal health-persuasive application that provides feedback on the user’s lifestyle, combining data from physical and virtual sensors. In this case of use, LIS is used to timely evaluate the user’s activity level, to decide on the convenience of triggering notifications and to determine the best interface or channel to deliver these context-aware alerts.

Evaluation of Nutritional Practices in the Critical Care Patient (The ENPIC Study): Does Nutrition Really Affect ICU Mortality?

Background & aims: The importance of artificial nutritional therapy is underrecognized, typically being considered an adjunctive rather than a primary therapy. We aimed to evaluate the influence of nutritional therapy on mortality in critically ill patients. Methods: This multicenter prospective observational study included adult patients needing artificial nutritional therapy for >48 h if they stayed in one of 38 participating intensive care units for >= 72 h between April and July 2018. Demographic data, comorbidities, diagnoses, nutritional status and therapy (type and details for <= 14 days), and outcomes were registered in a database. Confounders such as disease severity, patient type (e.g., medical, surgical or trauma), and type and duration of nutritional therapy were also included in a multivariate analysis, and hazard ratios (HRs) and 95% confidence intervals (95% CIs) were reported. Results: We included 639 patients among whom 448 (70.1%) and 191 (29.9%) received enteral and parenteral nutrition, respectively. Mortality was 25.6%, with non-survivors having the following char-acteristics: older age; more comorbidities; higher Sequential Organ Failure Assessment (SOFA) scores (6.6 +/- 3.3 vs 8.4 +/- 3.7; P < 0.001); greater nutritional risk (Nutrition Risk in the Critically Ill [NUTRIC] score: 3.8 +/- 2.1 vs 5.2 +/- 1.7; P < 0.001); more vasopressor requirements (70.4% vs 83.5%; P=0.001); and more renal replacement therapy (12.2% vs 23.2%; P=0.001). Multivariate analysis showed that older age (HR: 1.023; 95% CI: 1.008-1.038; P=0.003), higher SOFA score (HR: 1.096; 95% CI: 1.036-1.160; P=0.001), higher NUTRIC score (HR: 1.136; 95% CI: 1.025-1.259; P=0.015), requiring parenteral nutrition after starting enteral nutrition (HR: 2.368; 95% CI: 1.168-4.798; P=0.017), and a higher mean Kcal/Kg/day intake (HR: 1.057; 95% CI: 1.015-1.101; P=0.008) were associated with mortality. By contrast, a higher mean protein intake protected against mortality (HR: 0.507; 95% CI: 0.263-0.977; P=0.042). Conclusions: Old age, higher organ failure scores, and greater nutritional risk appear to be associated with higher mortality. Patients who need parenteral nutrition after starting enteral nutrition may represent a high-risk subgroup for mortality due to illness severity and problems receiving appropriate nutritional therapy. Mean calorie and protein delivery also appeared to influence outcomes. (C) 2021 The Author(s). Published by Elsevier Ltd on behalf of European Society for Clinical Nutrition and Metabolism

First observation of Bs -> D_{s2}^{*+} X mu nu decays

Using data collected with the LHCb detector in proton-proton collisions at a centre-of-mass energy of 7 TeV, the semileptonic decays Bs -> Ds+ X mu nu and Bs -> D0 K+ X mu nu are detected. Two structures are observed in the D0 K+ mass spectrum at masses consistent with the known D^+_{s1}(2536) and $D^{*+}_{s2}(2573) mesons. The measured branching fractions relative to the total Bs semileptonic rate are B(Bs -> D_{s2}^{*+} X mu nu)/B(Bs -> X mu nu)= (3.3\pm 1.0\pm 0.4)%, and B(Bs -> D_{s1}^+ X munu)/B(Bs -> X mu nu)= (5.4\pm 1.2\pm 0.5)%, where the first uncertainty is statistical and the second is systematic. This is the first observation of the D_{s2}^{*+} state in Bs decays; we also measure its mass and width.Comment: 8 pages 2 figures. Published in Physics Letters

Host adaptive immunity deficiency in severe pandemic influenza

INTRODUCTION: Pandemic A/H1N1/2009 influenza causes severe lower respiratory complications in rare cases. The association between host immune responses and clinical outcome in severe cases is unknown. METHODS: We utilized gene expression, cytokine profiles and generation of antibody responses following hospitalization in 19 critically ill patients with primary pandemic A/H1N1/2009 influenza pneumonia for identifying host immune responses associated with clinical outcome. Ingenuity pathway analysis 8.5 (IPA) (Ingenuity Systems, Redwood City, CA) was used to select, annotate and visualize genes by function and pathway (gene ontology). IPA analysis identified those canonical pathways differentially expressed (P < 0.05) between comparison groups. Hierarchical clustering of those genes differentially expressed between groups by IPA analysis was performed using BRB-Array Tools v.3.8.1. RESULTS: The majority of patients were characterized by the presence of comorbidities and the absence of immunosuppressive conditions. pH1N1 specific antibody production was observed around day 9 from disease onset and defined an early period of innate immune response and a late period of adaptive immune response to the virus. The most severe patients (n = 12) showed persistence of viral secretion. Seven of the most severe patients died. During the late phase, the most severe patient group had impaired expression of a number of genes participating in adaptive immune responses when compared to less severe patients. These genes were involved in antigen presentation, B-cell development, T-helper cell differentiation, CD28, granzyme B signaling, apoptosis and protein ubiquitination. Patients with the poorest outcomes were characterized by proinflammatory hypercytokinemia, along with elevated levels of immunosuppressory cytokines (interleukin (IL)-10 and IL-1ra) in serum. CONCLUSIONS: Our findings suggest an impaired development of adaptive immunity in the most severe cases of pandemic influenza, leading to an unremitting cycle of viral replication and innate cytokine-chemokine release. Interruption of this deleterious cycle may improve disease outcome.The study was scientifically sponsored by the Spanish Society for Critical Care Medicine (SEMICYUC). Funding: MICCIN-FIS/JCYL-IECSCYL-SACYL (Spain): Programa de Investigación Comisionada en Gripe, GR09/0021-EMER07/050- PI081236-RD07/0067. CIHR-NIH-Sardinia Recherché-LKSF Canada support DJK.S

Multicentre observational study on multisystem inflammatory syndrome related to COVID-19 in Argentina

Background: The impact of the pediatric inflammatory multisystem syndrome temporally associated with SARS-CoV-2 (PIMS-TS) in low- and middle-income countries remains poorly understood. Our aim was to understand the characteristics and outcomes of PIMS-TS in Argentina. Methods: This observational, prospective, and retrospective multicenter study enrolled patients younger than 18 years-old manifesting PIMS-TS, Kawasaki disease (KD) or Kawasaki shock syndrome (KSS) between March 2020 and May 2021. Patients were followed-up until hospital discharge or death (one case). The primary outcome was pediatric intensive care unit (PICU) admission. Multiple logistic regression was used to identify variables predicting PICU admission. Results: Eighty-one percent, 82%, and 14% of the 176 enrolled patients fulfilled the suspect case criteria for PIMS-TS, KD, and KSS, respectively. Temporal association with SARS-CoV-2 was confirmed in 85% of the patients and 38% were admitted to the PICU. The more common clinical manifestations were fever, abdominal pain, rash, and conjunctival injection. Lymphopenia was more common among PICU-admitted patients (87% vs. 51%, p < 0.0001), who also showed a lower platelet count and higher plasmatic levels of inflammatory and cardiac markers. Mitral valve insufficiency, left ventricular wall motion alterations, pericardial effusion, and coronary artery alterations were observed in 30%, 30%, 19.8%, and 18.6% of the patients, respectively. Days to initiation of treatment, rash, lymphopenia, and low platelet count were significant independent contributions to PICU admission. Conclusion: Rates of severe outcomes of PIMS-TS in the present study agreed with those observed in high-income countries. Together with other published studies, this work helps clinicians to better understand this novel clinical entity.Fil: Vainstein, Eduardo. Gobierno de la Ciudad de Buenos Aires. Hospital General de Niños "Ricardo Gutiérrez"; ArgentinaFil: Baleani, Silvia. Gobierno de la Ciudad de Buenos Aires. Hospital General de Niños "Ricardo Gutiérrez"; ArgentinaFil: Urrutia, Luis. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; ArgentinaFil: Affranchino, Nicolás. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; ArgentinaFil: Ackerman, Judith. Gobierno de la Ciudad de Buenos Aires. Hospital General de Niños Pedro Elizalde (ex Casa Cuna); ArgentinaFil: Cazalas, Mariana. Gobierno de la Ciudad de Buenos Aires. Hospital General de Niños "Ricardo Gutiérrez"; ArgentinaFil: Goldsman, Alejandro. Gobierno de la Ciudad de Buenos Aires. Hospital General de Niños "Ricardo Gutiérrez"; ArgentinaFil: Sardella, Angela. Gobierno de la Ciudad de Buenos Aires. Hospital General de Niños "Ricardo Gutiérrez"; ArgentinaFil: Tolin, Ana Laura. Gobierno de la Provincia de Mendoza. Hospital Pediátrico Humberto Notti; ArgentinaFil: Goldaracena, Pablo. Provincia de Buenos Aires. Ministerio de Salud. Hospital de Niños "Sor María Ludovica" de La Plata; ArgentinaFil: Fabi, Mariana. Provincia de Buenos Aires. Ministerio de Salud. Hospital de Niños "Sor María Ludovica" de La Plata; ArgentinaFil: Cosentino, Mariana. Hospital Británico de Buenos Aires; ArgentinaFil: Magliola, Ricardo. Hospital Británico de Buenos Aires; ArgentinaFil: Roggiero, Gustavo. Provincia de Buenos Aires. Ministerio de Salud. Hospital Alta Complejidad en Red El Cruce Dr. Néstor Carlos Kirchner Samic; ArgentinaFil: Manso, Paula. Provincia de Buenos Aires. Ministerio de Salud. Hospital Alta Complejidad en Red El Cruce Dr. Néstor Carlos Kirchner Samic; ArgentinaFil: Triguy, Jésica. Gobierno de la Provincia de Mendoza. Hospital Pediátrico Humberto Notti; ArgentinaFil: Ballester, Celeste. Gobierno de la Provincia de Mendoza. Hospital Pediátrico Humberto Notti; ArgentinaFil: Cervetto, Vanesa. Gobierno de la Ciudad de Buenos Aires. Hospital General de Niños Pedro Elizalde (ex Casa Cuna); ArgentinaFil: Vaccarello, María. Sanatorio de la Trinidad; ArgentinaFil: De Carli, Domingo Norberto. Clínica del Niño de Quilmes; ArgentinaFil: De Carli, Maria Estela. Clínica del Niño de Quilmes; ArgentinaFil: Ciotti, Ana Laura. Hospital Nacional Profesor Alejandro Posadas; ArgentinaFil: Sicurello, María Irene. Gobierno de la Ciudad de Buenos Aires. Hospital General de Niños "Ricardo Gutiérrez"; ArgentinaFil: Rios Leiva, Cecilia. Provincia de Buenos Aires. Ministerio de Salud. Hospital Interzonal de Agudos "Eva Perón"; ArgentinaFil: Villalba, Claudia. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; ArgentinaFil: Hortas, María. Sanatorio de la Trinidad; ArgentinaFil: Peña, Sonia. Gobierno de la Provincia de Mendoza. Hospital Pediátrico Humberto Notti; ArgentinaFil: González, Gabriela. Gobierno de la Provincia de Mendoza. Hospital Pediátrico Humberto Notti; ArgentinaFil: Zold, Camila Lidia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Fisiología y Biofísica Bernardo Houssay. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Fisiología y Biofísica Bernardo Houssay; ArgentinaFil: Murer, Mario Gustavo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Fisiología y Biofísica Bernardo Houssay. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Fisiología y Biofísica Bernardo Houssay; ArgentinaFil: Grippo, M.. No especifíca;Fil: Vázquez, H.. No especifíca;Fil: Morós, C.. No especifíca;Fil: Di Santo, M.. No especifíca;Fil: Villa, A.. No especifíca;Fil: Lazota, P.. No especifíca;Fil: Foti, M.. No especifíca;Fil: Napoli, N.. No especifíca;Fil: Katsikas, M. M.. No especifíca;Fil: Tonello, L.. No especifíca;Fil: Peña, J.. No especifíca;Fil: Etcheverry, M.. No especifíca;Fil: Iglesias, D.. No especifíca;Fil: Alcalde, A. L.. No especifíca;Fil: Bruera, M.J.. No especifíca;Fil: Bruzzo, V.. No especifíca;Fil: Giordano, P.. No especifíca;Fil: Pena Acero, F.. No especifíca;Fil: Netri Pelandi, G.. No especifíca;Fil: Pastaro, D.. No especifíca;Fil: Bleiz, J.. No especifíca;Fil: Rodríguez, M. F.. No especifíca;Fil: Laghezza, L.. No especifíca;Fil: Molina, M. B.. No especifíca;Fil: Patynok, N.. No especifíca;Fil: Chatelain, M. S.. No especifíca;Fil: Aguilar, M. J.. No especifíca;Fil: Gamboa, J.. No especifíca;Fil: Cervan, M.. No especifíca;Fil: Ruggeri, A.. No especifíca;Fil: Marinelli, I.. No especifíca;Fil: Checcacci, E.. No especifíca;Fil: Meregalli, C.. No especifíca;Fil: Damksy Barbosa, J.. No especifíca;Fil: Fernie, L.. No especifíca;Fil: Fernández, M. J.. No especifíca;Fil: Saenz Tejeira, M.M.. No especifíca;Fil: Cereigido, C.. No especifíca;Fil: Nunell, A.. No especifíca;Fil: Villar, D.. No especifíca;Fil: Mansilla, A. D.. No especifíca;Fil: Darduin, M. D.. No especifíca

Mosaic maternal ancestry in the Great Lakes region of East Africa

The Great Lakes lie within a region of East Africa with very high human genetic diversity, home of many ethno-linguistic groups usually assumed to be the product of a small number of major dispersals. However, our knowledge of these dispersals relies primarily on the inferences of historical, linguistics and oral traditions, with attempts to match up the archaeological evidence where possible. This is an obvious area to which archaeogenetics can contribute, yet Uganda, at the heart of these developments, has not been studied for mitochondrial DNA (mtDNA) variation. Here, we compare mtDNA lineages at this putative genetic crossroads across 409 representatives of the major language groups: Bantu speakers and Eastern and Western Nilotic speakers. We show that Uganda harbours one of the highest mtDNA diversities within and between linguistic groups, with the various groups significantly differentiated from each other. Despite an inferred linguistic origin in South Sudan, the data from the two Nilotic-speaking groups point to a much more complex history, involving not only possible dispersals from Sudan and the Horn but also large-scale assimilation of autochthonous lineages within East Africa and even Uganda itself. The Eastern Nilotic group also carries signals characteristic of West-Central Africa, primarily due to Bantu influence, whereas a much stronger signal in the Western Nilotic group suggests direct West-Central African ancestry. Bantu speakers share lineages with both Nilotic groups, and also harbour East African lineages not found in Western Nilotic speakers, likely due to assimilating indigenous populations since arriving in the region ~3000 years ago