Mentefactos conceptuales como estrategia para el aprendizaje de Estadística Inferencial en estudiantes universitarios / Conceptual diagrams used with university students as a strategy for learning Inferential Statistics

Introducción: Los mentefactos conceptuales como estrategia para el aprendizaje de la estadística inferencial desarrollan procesos cognitivos mediante diagramas, lo que estructura los temas conceptuales sobre la base de las operaciones intelectuales. Objetivo: Determinar el efecto de los mentefactos conceptuales como estrategia didáctica para el aprendizaje de Estadística Inferencial por estudiantes del IV ciclo de carrera profesional de psicología en la Universidad Peruana Los Andes. Métodos: Se ejecutaron una investigación experimental y un diseño pre experimental longitudinal con pre- y pos prueba. La muestra fue de 16 estudiantes del IV ciclo de la carrera profesional de psicología, matriculados en la asignatura de Estadística Inferencial. Se experimentaron los temas población y muestra y estimación estadística. Se aplicó una prueba objetiva de 10 ítems medidos en escala de razón. Los datos se procesaron mediante la estadística descriptiva y las pruebas de hipótesis. Resultados: En relación con el tema población y muestra, se demostró la significancia de la diferencia de medias en pre-y pos = 4,7 mayor que = 2,04 y α = 0,05; en la segunda fase el tema fue estimación estadística, en el cual la diferencia de medias en pre- y pos- resultaron significativos porque = 8,6 mayor que = 2,04, al aceptar la hipótesis alternativa. Conclusiones: Los mentefactos conceptuales como estrategia de aprendizaje de la Estadística Inferencial generó expectativas en estudiantes, quienes lograron su aprendizaje significativamente. Se reconoció la necesidad de aplicar sistemáticamente y con continuidad el modelo, dado que se obtiene mejor nivel de aprehensión de los conocimientos estadísticos(AU)

Introduction: Conceptual diagrams as a strategy for learning inferential statistics develop cognitive processes, structuring conceptual topics on the basis of intellectual operations. Objective: To determine the effect of conceptual diagrams as a didactic strategy for the learning of inferential statistics by students from the fourth cycle of the professional major of Psychology at Los Andes Peruvian University. Methods: An experimental research was carried out, together with a longitudinal, preexperimental, pre-test/post-test design. The sample consisted of sixteen students from the fourth cycle of the professional major in Psychology, enrolled in the Inferential Statistics subject. The topics about population and sample, as well as statistical estimation, were tested. An objective test of ten items measured on a ratio scale was applied. The data were processed using descriptive statistics and hypothesis testing. Results: Regarding the population and sample item, the significance of the difference in means between pre-test and post-test was demonstrated, being t cal =4.7, a value higher than t crit =2.04, and α=0.05. In the second phase, the topic was statistical estimation, for which the difference in means between pre-test and post-test resulted to be significant, because t cal =8.6, a value higher than t crit =2.04, by accepting the alternative hypothesis. Conclusions: Conceptual diagrams as a strategy for learning inferential statistics created expectations among students, who achieved their learning significantly. The need to apply the model systematically and continuously was recognized, given that a better level of apprehension of statistical knowledge is obtained(AU)

Teamwork to Survive in Hostile Soils: Use of Plant Growth-Promoting Bacteria to Ameliorate Soil Salinity Stress in Crops.

Plants and their microbiomes, including plant growth-promoting bacteria (PGPB), can work as a team to reduce the adverse effects of different types of stress, including drought, heat, cold, and heavy metals stresses, as well as salinity in soils. These abiotic stresses are reviewed here, with an emphasis on salinity and its negative consequences on crops, due to their wide presence in cultivable soils around the world. Likewise, the factors that stimulate the salinity of soils and their impact on microbial diversity and plant physiology were also analyzed. In addition, the saline soils that exist in Mexico were analyzed as a case study. We also made some proposals for a more extensive use of bacterial bioinoculants in agriculture, particularly in developing countries. Finally, PGPB are highly relevant and extremely helpful in counteracting the toxic effects of soil salinity and improving crop growth and production; therefore, their use should be intensively promoted.

Casi nula publicación científica de los médicos especialistas peruanos: Análisis de resultados en Google Académico y Scopus / Precarious scientific publication amongst Peruvian medical specialists: Analysis of results in Google Academics and Scopus

RESUMEN Introducción: Los médicos especialistas tienen un alto grado de preparación académica en su formación. Sin embargo, su producción científica no corresponde con su grado de preparación. Objetivo: Determinar la frecuencia de publicaciones científicas encontradas en Google Académico y Scopus de los médicos especialistas peruanos. Metodología: Estudio transversal analítico donde se hizo un muestreo aleatorio de los especialistas médicos registrados en el Colegio Médico del Perú durante el año 2017. A los seleccionados se los clasificó según si habían publicado en revistas que podían ser encontradas por el buscador Google Académico o que estuviesen indexadas a Scopus. Se reportó las cantidades totales de publicaciones y sus asociaciones estadísticas. Resultados: De los 2108 especialistas, 1810 (85,9 %) y 2027 (96,2 %) nunca han publicado en revistas científicas que pueda ser encontradas por Google Académico o indizadas a Scopus, respectivamente. Las especialidades que más resultados tuvieron en Google Académico fueron gastroenterología (46,3 %), dermatología (44,4 %) y neurología (42,5 %); en cambio, en Scopus fue neurología (15,0 %), gastroenterología y dermatología (ambas con 11,1 %), así como, patología (10,9 %). Lo máximo que un autor tuvo en revistas extranjeras de Scopus fue 4 artículos originales como corresponsal. Hubo asociaciones estadísticamente significativas según la menor cantidad de publicaciones de Scopus que tuvieron quince especialidades (todos los valores p<0,042), de las cuales, trece no tuvieron publicación alguna. Conclusiones: Los médicos especialistas no tienen una abundante producción científica. De manera que, es importante incentivar el desarrollo científico de los especialistas.

ABSTRACT Introduction: In industrialized countries there is large production of publications from specialized physicians on specific topics regarding their working areas. Reality is quite different in Peru. Objective: To determine the rates of scientific paper production found in Google Academics and Scopus, as well as their association with medical specialties. Methodology: This is an analytical cross-section study. Randomized sampling of medical specialists registered in the Peruvian College of Physicians was performed. Those who were selected were searched aiming to determine whether they had produced papers in publications that would be found in Google Academics or that would be indexed in the Scopus database. Their lifetime production was reported, together with statistical associations. Results: Out of 2108 specialized physicians, 1810 (85.9%) and 2027 (96.2%) had never produced any scientific publication that could have been found in Google Academics or in Scopus indexed journals, respectively. Specialties most frequently found in Google Academics were as follows: gastroenterology (46.3%), dermatology (44.4%), and neurology (42.5%). In Scopus, most frequently found specialties were neurology (15.0%), gastroenterology and dermatology (11.1%, both), and pathology (10.9%). The highest number of production in foreign Scopusindexed publications was 4 original papers for a corresponding author. There were statistically significant associations with respect to the lowest numbers of Scopus-indexed publications for 15 specialties (p<0.042 for all), and thirteen of them featured no scientific production at all. Conclusions: The low number of authors who published scientific papers was surprising, and this may serve as an alert about the low resources available for generating and publishing their research, so strategies for helping in this purpose should be established.

Concussion Pathophysiology and Injury Biomechanics.

PURPOSE OF REVIEW: The concussion public health burden has increased alongside our knowledge of the pathophysiology of mild traumatic brain injury (mTBI). The purpose of this review is to summarize our current understanding of mTBI pathophysiology and biomechanics and how these underlying principles correlate with clinical manifestations of mTBI. RECENT FINDINGS: Changes in post-mTBI glutamate and GABA concentrations seem to be region-specific and time-dependent. Genetic variability may predict recovery and symptom severity while gender differences appear to be associated with the neuroinflammatory response and neuroplasticity. Ongoing biomechanical research has shown a growing body of evidence in support of an "individual-specific threshold" for mTBI that varies based on individual intrinsic factors. The literature demonstrates a well-characterized timeframe for mTBI pathophysiologic changes in animal models while work in this area continues to grow in humans. Current human research shows that these underlying post-mTBI effects are multifactorial and may correlate with symptomatology and recovery. While wearable sensor technology has advanced biomechanical impact research, a definitive concussion threshold remains elusive.

El viaje de la homeopatía en México. Apuntes sobre una historia extraordinaria / The Journey of Homeopathy in Mexico. Notes about an Extraordinary Story

En este ensayo-reportaje se hace un recorrido a través de algunos de los momentos más significativos en la historia de la Homeopatía en México, desde sus orígenes hasta las primeras décadas del siglo XXI. Además de recordar la fundación de las instituciones más significativas para el gremio médico homeopático y su relación con el trabajo de algunos médicos connotados, se mencionan algunas investigaciones científicas de relevancia, las aportaciones reales y potenciales de la medicina hahnemanniana a la salud pública y la influencia que la Homeopatía mexicana ha tenido, principalmente en países hispanohablantes. (AU)

This essay-report presents a review of the most significant moments of homeopathy in Mexico, from its origins to the first decades of the 21st century. He recalls the founding of the most significant institutions for the homeopathic profession and its relationship with the work of some connoted doctors; also mentioned are relevant scientific researchs, the contributions of the hahnemannian medicine to public health and the influence of the Mexican homeopathy, mainly in Ibero-America. (AU)

Guatteria gaumeri, Malmea depressa o Yumel, una revisión sobre su historia, sus propiedades y su uso en la homeopatía / Guatteria gaumeri, Malmea depressa or yumel, a review of its history, its properties and its use in homeopathy

El elemuy, Guatteria gaumeri o Malmea depressa es un árbol que habita en México y Centroamérica, y que debido a las propiedades medicinales de su corteza y su raíz ha sido aprovechado desde la época prehispánica para atender afecciones renales, diabetes mellitus tipo II e hipercolesterolemia, entre otras enfermedades. A principios del siglo XX llamó la atención del médico homeópata mexicano Manuel A. Lizama, quien probó su uso durante una década y registró sus observaciones en el Prontuario de materia médica, publicado en 1913. Desde entonces se han realizado diversas investigaciones dentro y fuera del ámbito homeopático que han confirmado y precisado cuál es la acción medicamentosa de la alfa-asarona y otros componentes del elemuy, pero también han sugerido nuevos atributos que sería conveniente comprobar o descartar a través de estudios científicos. El presente texto hace un recorrido por algunos de los artículos representativos que se han generado sobre la Guatteria gaumeri o Malmea depressa, con la finali ad de que médicos, estudiantes e investigadores actualicen o mejoren sus conocimientos. (AU)

The Elemuy, Guatteria gaumeri or Malmea depressa is a tree that grows in Mexico and Central America, and because of the medicinal properties of his bark and roots, it has been used since pre-hispanic times to treat kidney disease, type II diabetes mellitus and hypercholesterolemia, among other diseases. In the early twentieth century it drew the attention of Dr. Manuel A. López a Mexican homeopath, who proved it´s use for a decade and recorded his observations at the Prontuario de Materia Medica, published in 1913. Since then there have been performed several research works into, and out of the homeopathic field that have confirmed and specified the pharmacological action of the alpha-asarone among other components of the Elemuy, but also, new pharmacological properties have been suggested that it would be important to test through scientific works. This text takes us through some representative articles that have been generated on the Guatteria gaumeri or Malmea depressa, in order that doctors, students and researchers update or improve their knowledge about this theme. (AU)

Guatteria gaumeri, Malmea depressa o Yumel, una revisión sobre su historia, sus propiedades y su uso en la homeopatía / Guatteria gaumeri, Malmea depressa or yumel, a review of its history, its properties and its use in homeopathy

El elemuy, Guatteria gaumeri o Malmea depressa es un árbol que habita en México y Centroamérica, y que debido a las propiedades medicinales de su corteza y su raíz ha sido aprovechado desde la época prehispánica para atender afecciones renales, diabetes mellitus tipo II e hipercolesterolemia, entre otras enfermedades. A principios del siglo XX llamó la atención del médico homeópata mexicano Manuel A. Lizama, quien probó su uso durante una década y registró sus observaciones en el Prontuario de materia médica, publicado en 1913. Desde entonces se han realizado diversas investigaciones dentro y fuera del ámbito homeopático que han confirmado y precisado cuál es la acción medicamentosa de la alfa-asarona y otros componentes del elemuy, pero también han sugerido nuevos atributos que sería conveniente comprobar o descartar a través de estudios científicos. El presente texto hace un recorrido por algunos de los artículos representativos que se han generado sobre la Guatteria gaumeri o Malmea depressa, con la finali ad de que médicos, estudiantes e investigadores actualicen o mejoren sus conocimientos...

The Elemuy, Guatteria gaumeri or Malmea depressa is a tree that grows in Mexico and Central America, and because of the medicinal properties of his bark and roots, it has been used since pre-hispanic times to treat kidney disease, type II diabetes mellitus and hypercholesterolemia, among other diseases. In the early twentieth century it drew the attention of Dr. Manuel A. López a Mexican homeopath, who proved it´s use for a decade and recorded his observations at the Prontuario de Materia Medica, published in 1913. Since then there have been performed several research works into, and out of the homeopathic field that have confirmed and specified the pharmacological action of the alpha-asarone among other components of the Elemuy, but also, new pharmacological properties have been suggested that it would be important to test through scientific works. This text takes us through some representative articles that have been generated on the Guatteria gaumeri or Malmea depressa, in order that doctors, students and researchers update or improve their knowledge about this theme...

An Lrp-type transcriptional regulator controls expression of the Bacillus subtilis chromate transporter.

The Bacillus subtilis strain 168 genome contains the chr3N-chr3C genes encoding the Chr3N/Chr3C protein pair of the chromate ion transporter (CHR) superfamily. Chr3N/Chr3C confers chromate resistance in Escherichia coli only when both proteins are expressed. Upstream of chr3N is the chrS gene encoding ChrS, a protein with homology to the Lrp/AsnC family of transcriptional regulators. When the chrS-chr3N-chr3C gene cluster was transferred to E. coli, a diminished level of chromate resistance was observed, as compared with E. coli transformants bearing only the chromate resistance genes, which displayed full resistance. These data suggested that the chrS gene product acts as negative regulator. RT-PCR assays demonstrated that expression of chrS diminishes transcription of the chromate resistance genes in E. coli, and that this repression was overcome by chromate. Electrophoretic mobility shift assays showed that purified ChrS protein specifically binds to the 5' region of chrS. These results indicate that the chr gene cluster forms an operon regulated negatively by ChrS binding to its own gene's regulatory region, and positively by chromate ions. Sequence analysis revealed similar operons in many Bacillales strains, suggesting some adaptive advantage. This is the first example of a bacterial heavy-metal resistance system controlled by an Lrp-type transcriptional regulator.

Membrane topology of the chromate transporter ChrA of Pseudomonas aeruginosa.

The membrane topology of the plasmid-encoded Pseudomonas aeruginosa ChrA protein, which effluxes chromate ions, was determined by the analysis of translational fusions with reporter enzymes alkaline phosphatase and beta-galactosidase. A novel 13-TMS (transmembrane segments) topology, with the N-terminus located in the cytoplasm and the C-terminus in the periplasmic space, was consistent with the enzyme activities determined in both Escherichia coli and P. aeruginosa. Alignment of the two halves of ChrA showed significant sequence homology, with TMS I, II, III, IV, V and VI displaying similarity to TMS VIII, IX, X, XI, XII and XIII, respectively, although with opposite membrane orientations. This suggests that ChrA arose from the duplication of a gene encoding a 6-TMS ancestral protein, followed by the insertion of extra TMS VII. These data also suggest that the two halves of ChrA may carry out distinct functions for the transport of chromate.

Inestabilidad anterolateral del tobillo / Anterolateral ankle inestability

Se presenta una tecnica personal en el tratamiento quirurgico de la inestabilidad anterior del tobillo con 36 cirugias en 34 pacientes, los cuales se han seguido durante 8 meses. Los resultados finales son discutidos en comparacion con otras tecnicas quirurgicas