Abandono y permanencia estudiantil en universidades de Latinoamérica y el Caribe: Una revisión sistemática mixta

La educación superior es un derecho humano clave para el desarrollo de las personas y las sociedades. América Latina y el Caribe presentan tasas de abandono superiores a otras regiones. Este artículo muestra una revisión exhaustiva de la evidencia sobre abandono y permanencia de estudiantes en universidades latinoamericanas y caribeñas entre 1992 y 2022. Se desarrolló una revisión sistemática mixta que siguió las directrices del protocolo PRISMA. Se identificaron 217 estudios que cumplieron con los criterios definidos. En consideración con la naturaleza compleja del fenómeno, se adoptó un enfoque ecológico mediante la agrupación de la evidencia en 67 variables y cuatro niveles: sujeto, institución, sistema educativo y contexto macrosocial. La mayoría de los estudios se enfocan en el nivel sujeto, seguido del nivel institucional. Predominan investigaciones vinculadas al abandono (76 %) respecto a aquellas enfocadas en la permanencia (24 %). Prevalecieron estudios con metodología cuantitativa (76 %) sobre los cualitativos (10 %) y mixtos (14 %). Un 25 % de los trabajos tuvieron un alcance explicativo, donde predominan estudios de tipo descriptivo y correlacional, lo cual evidencia la necesidad de incrementar la complejidad de los diseños metodológicos. Los hallazgos brindan un mapa de evidencia actualizado sobre el abandono y la permanencia en la educación superior para la región. Asimismo, se presentan aportes para contribuir al desarrollo de futuras investigaciones, lineamientos útiles para la construcción de sistemas de alerta temprana orientados a la prevención del abandono y claves para el diseño de intervenciones institucionales que favorezcan la permanencia estudiantil a nivel universitario

The Genome of Anopheles darlingi, the main neotropical malaria vector

Anopheles darlingi is the principal neotropical malaria vector, responsible for more than a million cases of malaria per year on the American continent. Anopheles darlingi diverged from the African and Asian malaria vectors ∼100 million years ago (mya) and successfully adapted to the New World environment. Here we present an annotated reference A. darlingi genome, sequenced from a wild population of males and females collected in the Brazilian Amazon. A total of 10 481 predicted protein-coding genes were annotated, 72% of which have their closest counterpart in Anopheles gambiae and 21% have highest similarity with other mosquito species. In spite of a long period of divergent evolution, conserved gene synteny was observed between A. darlingi and A. gambiae. More than 10 million single nucleotide polymorphisms and short indels with potential use as genetic markers were identified. Transposable elements correspond to 2.3% of the A. darlingi genome. Genes associated with hematophagy, immunity and insecticide resistance, directly involved in vectorhuman and vectorparasite interactions, were identified and discussed. This study represents the first effort to sequence the genome of a neotropical malaria vector, and opens a new window through which we can contemplate the evolutionary history of anopheline mosquitoes. It also provides valuable information that may lead to novel strategies to reduce malaria transmission on the South American continent. The A. darlingi genome is accessible at www.labinfo.lncc.br/index.php/anopheles- darlingi. © 2013 The Author(s)

¿Se reproduce la segregación urbana de la Región Metropolitana a nivel comunal? Un análisis educacional y territorial de la comuna de Puente Alto.

El presente artículo analiza el fenómeno de la segregaciónurbana en sus manifestaciones socioeconómicay educacional. Se explora las definicionesy diversas manifestaciones de la segregaciónen la Región Metropolitana de Santiago – Chile(RM), centrando el análisis en la realidad educativade la comuna de Puente Alto. En particular, seaborda en profundidad los fenómenos de la segregaciónresidencial y segregación educacional,dando a conocer cómo se comportan ambos fenó-menos en Puente Alto, la comuna que concentramayor cantidad de viviendas sociales a nivel nacional.Los establecimientos educacionales de lacomuna fueron georreferenciados vinculando suubicación con el Nivel Socioeconómico (NSE) delas familias que acogen, el copago de las escuelasy su rendimiento en SIMCE y PSU. Se demuestraque la segregación en la RM también se reproduceen la comuna analizada, la cual además de estarsegregada territorialmente en la RM mantienepatrones de segregación educacional entre sushabitantes.This article analyzes the socioeconomic and educationalexpressions of urban segregation. It exploresdefinitions and diverse manifestations ofsegregation in Región Metropolitana of Santiago- Chile, and focuses on the educational reality ofPuente Alto. It deals mainly with urban residentialand educational segregation, showing howboth phenomena occur in Puente Alto, the areathat concentrates most social housing in Chile.Educational institutions in Puente Alto were georeferencedand their location was matched withthe socioeconomic status of families they host,payment for education and its results in SIMCEand PSU. The study shows that the segregationin RM is also reproduced in Puente Alto, an areathat, besides being segregated in terms of territory,keeps educational segregation patterns betweenits population

¿Se reproduce la segregación urbana de la Región Metropolitana a nivel comunal? Un análisis educacional y territorial de la comuna de Puente Alto.

El presente artículo analiza el fenómeno de la segregación urbana en sus manifestaciones socioeconómica y educacional. Se explora las definiciones y diversas manifestaciones de la segregación en la Región Metropolitana de Santiago – Chile (RM), centrando el análisis en la realidad educativa de la comuna de Puente Alto. En particular, se aborda en profundidad los fenómenos de la segregación residencial y segregación educacional, dando a conocer cómo se comportan ambos fenó- menos en Puente Alto, la comuna que concentra mayor cantidad de viviendas sociales a nivel nacional. Los establecimientos educacionales de la comuna fueron georreferenciados vinculando su ubicación con el Nivel Socioeconómico (NSE) de las familias que acogen, el copago de las escuelas y su rendimiento en SIMCE y PSU. Se demuestra que la segregación en la RM también se reproduce en la comuna analizada, la cual además de estar segregada territorialmente en la RM mantiene patrones de segregación educacional entre sus habitantes

Dry needling technique decreases spasticity and improves general functioning in incomplete spinal cord injury: a case report

Context: Spasticity in neurological disorders (i.e. stroke patients and cerebral palsy) is positively improved by dry needling. However, reports are scarce regarding the potential effects of dry needling in reducing spasticity and improving functionality in patients with an incomplete spinal cord injury. The aim of this case report was to study the immediate, short-term effects of dry needling treatment (10 weeks) on spasticity, dynamic stability, walking velocity, self-independence, and pain in a single patient with an incomplete spinal cord injury. Findings: The dry needling treatment resulted in immediate, short-time effects on basal spasticity in the upper (reduction from 2 to 0 point median) and lower (reduction from 2 to 0 point median) limbs, as measured by the modified Ashworth Scale. Dynamic-stability, assessed by trunk accelerometry, improved more than 50% (Root Mean Squared of acceleration, Root Mean Squared of Jerk and step variability), and gait speed improved by 24.7 s (i.e. time to walk 20 m). Self-independence and pain were respectively scored by the Spinal Cord Independence Measure (21 points improvement) and visual analog scale (4 points improvement). Conclusions: This case report demonstrates that dry needling treatment can have positive effects on spasticity, dynamic stability, walking velocity, self-independence, and pain in patients with incomplete spinal cord injury. Further research is needed in a larger patient population to deeply understand the mechanism(s) associated with the obtained results and regarding the clinical significances of dry needling treatment for incomplete spinal cord injury

Synthesis and Characterization of Magnetite/Gold Core Shell Nanoparticles Stabilized with a β-Cyclodextrin Nanosponge to Develop a Magneto-Plasmonic System

Magnetite/gold core-shell nanoparticles (magnetite/gold NPs) have important optical and magnetic properties that provide potential for applications, especially biomedical ones. However, their preparation is not exempt from difficulties that might lead to unexpected or undesired structures. This work reports the synthesis and characterization of magnetite/gold NPs using tetramethylammonium hydroxide (TMAH) to promote the formation of a continuous interface between the magnetite core and the thin gold shell. The synthesized magnetite/gold NPs were characterized using transmission electron microscopy (TEM), energy-dispersive spectroscopy (EDS), field emission scanning electron microscope (FE-SEM), ζ-potential, vibrating sample magnetometer (VSM), selected area electron diffraction (SAED), UV-Visible spectroscopy, and dynamic light scattering (DLS), confirming the core-shell structure of the NPs with narrow size distribution while evidencing its plasmonic and superparamagnetic properties as well. Further, the magnetite/gold NPs were associated and stabilized with a β-cyclodextrin nanosponge (β-CDNSs), obtaining a versatile magneto-plasmonic system for potential applications in the encapsulation and controlled release of drugs

Arsenic and cadmium bioremediation by antarctic bacteria capable of biosynthesizing CdS fluorescent nanoparticles

Use of microorganisms in contaminated water remediation is one of the most studied processes of recent years. The recovery of metal contaminants by converting them into high-value nanomaterials represents a scarcely explored topic with high potential economic impact. In this work, the authors determine the capacity to remove As and Cd from aqueous solutions by Antarctic bacteria previously reported as capable of biosynthesizing CdS fluorescent nanoparticles (NPs) at low temperatures. Bacterial characteristics favoring metal bioremediation, such as As and Cd resistance as well as high biofilm formation and metal removal (kinetic/sorption tests), were determined in Antarctic strains. In addition, the effect of As on the biosynthesis of CdS fluorescent NPs [quantum dots (QDs)] was evaluated. The presence of As inhibits the biosynthesis of CdS QDs by Antarctic bacteria. Arsenic inhibition does not involve the disruption of the Cd nanostructure or a decrease in H2S levels produced by cells, suggesting that As inhibits CdS biosynthesis by avoiding the interaction of Cd2+ with S2- required to produce the nanocrystal. Obtained results have significant consequences for the development of metal bioremediation strategies aimed at removing environmental heavy metals through the generation of NPs.Fil: Glatstein, Daniel Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Estudios Avanzados en Ingeniería y Tecnología. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto de Estudios Avanzados en Ingeniería y Tecnología; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales; ArgentinaFil: Bruna, Nicolás. Universidad Andres Bello. Centro de Bioinformatica y Biología Integrativa; ChileFil: Gallardo-Benavente, Carla. Universidad Andres Bello. Centro de Bioinformatica y Biología Integrativa; ChileFil: Bravo, Denisse. Universidad de Chile; ChileFil: Carro Pérez, Magalí Evelín. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Estudios Avanzados en Ingeniería y Tecnología. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto de Estudios Avanzados en Ingeniería y Tecnología; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales; ArgentinaFil: Francisca, Franco Matias. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Estudios Avanzados en Ingeniería y Tecnología. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto de Estudios Avanzados en Ingeniería y Tecnología; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales; ArgentinaFil: Pérez Donoso, José M.. Universidad Andres Bello. Centro de Bioinformatica y Biología Integrativa; Chil

A surface functionalized with per-(6-amino-6-deoxy)-β-cyclodextrin for potential organic pollutant removal from water

In this work, we present a solid silicon substrate functionalized with modified beta-cyclodextrin monolayers as an optimal surface for organic contaminant uptake. The inclusion and capture of three potential pollutants, 4-chlorophenoxyacetic acid, 4-aminobenzoic acid and phenylethylamine, were studied. H-1-NMR and ROESY studies revealed the complete inclusion and details of the conformational orientation of the three guests in the per-(6-amino-6-deoxy)-beta-cyclodextrin matrix, forming three new inclusion complexes that have not yet been reported. Capture assays for the guests were carried out by immersing the substrates in an aqueous pollutant solution and by measuring the UV-vis spectra. This substrate showed a high sorption capacity at equilibrium, between 2.5x10(-5) and 6.0x10(-5) mmol/substrate, for the studied pollutants. In addition, this surface can be reused four times with an efficiency equal to the initial use. Therefore, it could be a versatile platform that could be applied for the capture of other organic pollutants from water.Comisión Nacional de Investigación Científica y Tecnológica (CONICYT) CONICYT FONDECYT Projects PIA Anillo Millennium Nucleus Multifunctional Material for Surface Science Applications Comisión Nacional de Investigación Científica y Tecnológica (CONICYT