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Finding communities in gene co-expression networks is a common first step toward extracting biological insight from these complex datasets. Most community detection algorithms expect genes to be organized into assortative modules, that is, groups of genes that are more associated with each other than with genes in other groups. While it is reasonable to expect that these modules exist, using methods that assume they exist a priori is risky, as it guarantees that alternative organizations of gene interactions will be ignored. Here, we ask: can we find meaningful communities without imposing a modular organization on gene co-expression networks, and how modular are these communities? For this, we use a recently developed community detection method, the weighted degree corrected stochastic block model (SBM), that does not assume that assortative modules exist. Instead, the SBM attempts to efficiently use all information contained in the co-expression network to separate the genes into hierarchically organized blocks of genes. Using RNAseq gene expression data measured in two tissues derived from an outbred population of Drosophila melanogaster, we show that (a) the SBM is able to find ten times as many groups as competing methods, that (b) several of those gene groups are not modular, and that (c) the functional enrichment for non-modular groups is as strong as for modular communities. These results show that the transcriptome is structured in more complex ways than traditionally thought and that we should revisit the long-standing assumption that modularity is the main driver of the structuring of gene co-expression networks.

El propósito de este estudio fue evaluar la asociación de las larvas de odonatos con las raíces de Eichhornia crassipes en la ciénaga La Larga. Para el muestreo de las larvas de odonatos se utilizaron técnicas estandarizadas para macroinvertebrados acuáticos. Se realizaron seis muestreos, y en cada uno se colectaron 100 individuos de E. crassipes, de los cuales se midieron la longitud y el volumen de las raíces. Se colectaron un total de 738 individuos y 10 especies de odonatos. Entre ellos, Miathyria marcella presentó la mayor abundancia, con el 83 % del total muestreado. El porcentaje de ocupación de las raíces de E. crassipes por las larvas de Odonata fue del 58 % (346 de las 600 raíces recolectadas). Las raíces recolectadas presentaron medidas entre 5-58 cm de largo y volúmenes entre 5-450 mL. Se encontraron diferencias significativas en la composición y la estructura de las larvas respecto al volumen de las raíces. Las longitudes de las larvas variaron entre 2,4-24,3 mm, y la mayoría de los individuos colectados se encontró en el rango de longitud entre 5,1-10 mm. En conclusión, el tamaño de la raíz no es un determinante para la distribución de los odonatos en las raíces de E. crassipes, mientras que el volumen de las raíces de E. crassipes sí influyó en la composición de larvas.

Based on the available literature and a review of collections of organisms, a checklist of 69 myriapod species was made for the Colombian Caribbean region; two symphyls, 15 Chilopods, and 52 Diplopods. In total, 20 families (one from Symphyla, five from Chilopoda, and 14 from Diplopoda), from 11 orders (one from Symphyla, three from Chilopoda, and seven from Diplopoda). Each species's geographical range by department, altitud, reference collection, and bibliographic source were included. The presence in Colombian collections of diplopod specimens that are new records of their taxonomic group for the region, such as Chondrodesmus cf. riparius (Chelodesmidae), two species of Fuhrmannodesmidae, three of Paradoxosomatidae and one of Lophoproctidae. Likewise, two species of Scolopendrellidae of the class Symphyla. This demonstrates the urgent need to complete the essential diversity inventories of the main groups of organisms in the face of the alarming environmental deterioration to which the Colombian Caribbean region is subjected.

La viabilidad del polen es un parámetro fundamental en la formación de la semilla, existen diferentes técnicas para su evaluación, de las cuales la germinación in vitro, presenta resultados confiables. El polen de maíz tiene dificultad para germinar en medios de cultivo debido a la morfología y fisiología. Este estudio, tuvo como objetivo evaluar cinco formulaciones de germinación in vitro sobre polen de maíz del híbrido Synko sembrada bajo las condiciones climáticas de la ciudad de Santa Marta-Colombia. El periodo de antesis se dio 50 días después de la siembra; los granos de polen recolectados fueron puestos de inmediato, sobre cinco medios de cultivo ya referenciados en maíz, los cuales están constituidos por diferentes formulaciones de agar - agar, sacarosa, nitrato de calcio y ácido bórico. El arreglo estadístico fue un diseño completo al azar, ocho repeticiones por tratamiento y dos replicas en el tiempo. El conteo de granos de polen viables se hizo sobre cuatro campos por caja de petri, sobre 50 granos por campo, para el conteo, se empleó un estéreo microscopio Leica M205, y en un microscopio compuesto de luz a 40X. Se utilizó como referencia de viabilidad la tinción con acetocarmin al 2 %, en 10 portaobjetos por réplica, 100 granos de polen por portaobjetos. El medio constituido por 0,6 % de agar-agar, 17 % de sacarosa, y 0,03 % de nitrato de calcio, registró los valores más alto de germinación de granos de polen; este fue de 70,13 %. La tinción del polen con acetocarmin superó los porcentajes de viabilidad in vitro.

Abstract Objective To evaluate the sensitivity and specificity of the Allplex™ Entero-DR, a quantitative PCR-based method, for the detection of β-lactamase-encoding genes and vancomycin-resistance determinants in 156 previously characterized Gram-negative bacilli and Enterococcus spp. from bacterial cultures. Result The method had 100% sensitivity and between 92 and 100% of specificity for identifying bla KPC, bla VIM, bla IMP, bla NDM, bla OXA-48-like, bla CTX-M and vanA. In nine isolates, unspecific amplifications were detected. The Ct of these false positives was above 33. The Ct of the correctly identified bla and van genes did not surpass 28 and 30, respectively. None of the clinical isolates included as negative controls yielded any amplification. Therefore, the Allplex™ Entero-DR assay is a highly accurate test for the detection of important antibiotic resistance determinants. With this assay, reliable results can be obtained within 3 h. However, according to our data, samples with Ct values greater than 33 should be considered with caution.

Individual animals vary in their behaviors. This is true even when they share the same genotype and were reared in the same environment. Clusters of covarying behaviors constitute behavioral syndromes, and an individual’s position along such axes of covariation is a representation of their personality. Despite these conceptual frameworks, the structure of behavioral covariation within a genotype is essentially uncharacterized and its mechanistic origins unknown. Passing hundreds of inbred Drosophila individuals through an experimental pipeline that captured hundreds of behavioral measures, we found sparse but significant correlations among small sets of behaviors. Thus, the space of behavioral variation has many independent dimensions. Manipulating the physiology of the brain, and specific neural populations, altered specific correlations. We also observed that variation in gene expression can predict an individual’s position on some behavioral axes. This work represents the first steps in understanding the biological mechanisms determining the structure of behavioral variation within a genotype.

Rare genetic variants in yeast explain a large amount of phenotypic variation in a complex trait like growth.

One of the main challenges in ecology, biogeography and evolution is to understand and predict how species may respond to environmental changes. Here we focus on the deep subterranean environment, a system that minimizes most of the typical uncertainties of studies on epigean (surface) environments. Caves are relatively homogeneous habitats with nearly constant environmental conditions and simplified biological communities, allowing to control for biotic interactions. Thus, this particular system could be considered a natural habitat whose environmental conditions are similar to what can be reproduced in a laboratory, being an ideal model system for ecological, biogeographical and evolutionary studies. Subterranean species may potentially be used to assess the capability to persist in situ in a global change scenario, as they cannot accommodate to drastic changing conditions by behavioural plasticity, microhabitat use or by migrating to distant, more suitable areas, something frequent in epigean environments. In order to provide accurate predictions of the response of the subterranean biodiversity to climate change, we encourage evolutionary biologist, biogeographers and conservation biologist to work in this interesting ecosystem.

We recently provided evidence that an intrinsic reward-related signal—triggered by successful learning in absence of any external feedback—modulated the entrance of new information into long-term memory via the activation of the dopaminergic midbrain, hippocampus, and ventral striatum (the SN/VTA-Hippocampal loop; Ripollés et al., 2016). Here, we used a double-blind, within-subject randomized pharmacological intervention to test whether this learning process is indeed dopamine-dependent. A group of healthy individuals completed three behavioral sessions of a language-learning task after the intake of different pharmacological treatments: a dopaminergic precursor, a dopamine receptor antagonist or a placebo. Results show that the pharmacological intervention modulated behavioral measures of both learning and pleasantness, inducing memory benefits after 24 hr only for those participants with a high sensitivity to reward. These results provide causal evidence for a dopamine-dependent mechanism instrumental in intrinsically regulated learning and further suggest that subject-specific reward sensitivity drastically alters learning success.

Numerous loci of large effect have been shown to underlie phenotypic variation between species. However, loci with subtle effects are presumably more frequently involved in microevolutionary processes but have rarely been discovered. We explore the genetic basis of shape variation in the first upper molar of hybrid mice between Mus musculus musculus and M. m. domesticus. We performed the first genome-wide association study for molar shape and used 3D surface morphometrics to quantify subtle variation between individuals. We show that many loci of small effect underlie phenotypic variation, and identify five genomic regions associated with tooth shape; one region contained the gene microphthalmia-associated transcription factor Mitf that has previously been associated with tooth malformations. Using a panel of five mutant laboratory strains, we show the effect of the Mitf gene on tooth shape. This is the first report of a gene causing subtle but consistent variation in tooth shape resembling variation in nature.

In Colombia, detailed knowledge of the geographic distribution of gymnophthalmid lizards is scarce. This paper presents the first confirmed records of Leposoma rugiceps and provides additional records of Gymnophthalmus speciosus from Department of La Guajira, in the Colombian Caribbean Region. These records extend the geographical distribution of both species and support their wide distribution in the lowlands of north of Colombia. Furthermore, we provide an updated distribution map with known occurrences of these species in Colombia.

Background. The Barcelona Music Reward Questionnaire (BMRQ) questionnaire investigates the main facets of music experience that could explain the variance observed in how people experience reward associated with music. Currently, only English and Spanish versions of this questionnaire are available. The objective of this study is to validate a French version of the BMRQ. Methods. The original BMRQ was translated and adapted into an international French version. The questionnaire was then administered through an online survey aimed at adults aged over 18 years who were fluent in French. Statistical analyses were performed and compared to the original English and Spanish version for validation purposes. Results. A total of 1,027 participants completed the questionnaire. Most responses were obtained from France (89.4%). Analyses revealed that congruence values between the rotated loading matrix and the ideal loading matrix ranged between 0.88 and 0.96. Factor reliabilities of subscales (i.e., Musical Seeking, Emotion Evocation, Mood Regulation, Social Reward and Sensory-Motor) also ranged between 0.88 and 0.96. In addition, reliability of the overall factor score (i.e., Music reward) was 0.91. Finally, the internal consistency of the overall scale was 0.85. The factorial structure obtained in the French translation was similar to that of the original Spanish and English samples. Conclusion. The French version of the BMRQ appears valid and reliable. Potential applications of the BMRQ include its use as a valuable tool in music reward and emotion research, whether in healthy individuals or in patients suffering from a wide variety of cognitive, neurologic and auditory disorders.

RESUMEN Para este estudio, se aplicó una encuesta a veinte ganaderos de un grupo de gestión empresarial de ganaderos del Valle de Ubaté y Chiquinquirá (Colombia), que incluyó variables relacionadas con prácticas de prevención y de control de la mastitis bovina, para la obtención de leche de alta calidad. Para el análisis de todas las respuestas, se utilizó estadística descriptiva. Las prácticas ganaderas presentaron diferentes porcentajes de implementación, donde el 10% realizó el peluqueado de las ubres, el 75% de los ganaderos evaluados ordenaron correctamente la secuencia de la rutina del ordeño, el 90% practicó el despunte y alguna práctica de higienización de la ubre, como el lavado o el presellado y segregaron vacas, en casos de mastitis clínica, en el 70%. El sellado de los pezones, se efectuó en el 95% de los casos, como también una correcta cobertura del sellador; la identificación de vacas tratadas con antibióticos, se efectuó en el 75% de las fincas. El 90% de los ganaderos conocen el concepto de inhibidores en la leche y la terapia de la vaca seca fue implementada por el 30% de los productores. Las buenas prácticas de ordeño son aspectos de manejo que todos los productores deben utilizar rutinariamente, con el fin de generar beneficios para la obtención de leche de mejor calidad y es la forma inicial para competir en mercados externos altamente competitivos.SUMMARY For this study, an inquiry was applied to 20 milk producers, pertaining to an enterprise group of management from the Valleys of Ubaté and Chiquinquirá (Colombia), which included variables related to the prevention practice and the control of bovine mastitis with the aim of obtaining an excellent milk quality. For the analysis of all answers a descriptive statistic was used. The cattle management practices, applied by the cattlemen, presented different percentages regarding the implementation: 10% accomplished the blunting, 75% of the evaluated cattleman ordered properly the sequence of the milking routine, 90% practiced the washings or the predipping of the udders, a 70% segregated cows if a clinic mastitis case was detected; the sealing of the nipples took place in a 95% of the cases, also a correct cover of the sealant was presented. The identification of the treated cows with antibiotic was achieved in a 75% of the farms, the 90% of the cattlemen know the concept of milk inhibitors and the dry cow therapy was implemented by the 30% of the producers. Good milking practices are relevant aspects which should be known and applied routinely by the producers, since they generate benefits for obtaining an excellent milk quality and it conforms also the initial path to compete with highly competitive foreign markets.

Se evaluó la variación espacial y temporal de las comunidades de náyades de odonatos y su asociación al estado de rehabilitación de hábitat en los humedales La Vaca y Santa María del Lago. Se realizaron cuatro muestreos en cada humedal a lo largo de un año; utilizando técnicas estandarizadas de colecta de macroinvertebrados en puntos a la entrada, salida y espejos de agua de los humedales. Se encontró un gradiente en la distribución de la abundancia de las náyades observado en ambos humedales, donde la comunidad de náyades presenta mayor número de ejemplares en los puntos de muestreos que espacialmente se ubican a mayores distancias de los sitios de vertimientos. Al comparar la composición entre los humedales La Vaca y Santa María del Lago se encontró heterogeneidad de las comunidades de ambos humedales mediante la evaluación de la diversidad beta. El gradiente en la distribución de la abundancia de las náyades observado en ambos humedales, se ajusta más a una respuesta de las especies en términos de tolerancia a las variables ambientales.

Para este estudio, se aplicó una encuesta a veinte ganaderos de un grupo de gestión empresarial de ganaderos del Valle de Ubaté y Chiquinquirá (Colombia), que incluyó variables relacionadas con prácticas de prevención y de control de la mastitis bovina, para la obtención de leche de alta calidad. Para el análisis de todas las respuestas, se utilizó estadística descriptiva. Las prácticas ganaderas presentaron diferentes porcentajes de implementación, donde el 10% realizó el peluqueado de las ubres, el 75% de los ganaderos evaluados ordenaron correctamente la secuencia de la rutina del ordeño, el 90% practicó el despunte y alguna práctica de higienización de la ubre, como el lavado o el presellado y segregaron vacas, en casos de mastitis clínica, en el 70%. El sellado de los pezones, se efectuó en el 95% de los casos, como también una correcta cobertura del sellador; la identificación de vacas tratadas con antibióticos, se efectuó en el 75% de las fincas. El 90% de los ganaderos conocen el concepto de inhibidores en la leche y la terapia de la vaca seca fue implementada por el 30% de los productores. Las buenas prácticas de ordeño son aspectos de manejo que todos los productores deben utilizar rutinariamente, con el fin de generar beneficios para la obtención de leche de mejor calidad y es la forma inicial para competir en mercados externos altamente competitivos.