Higher-order interactions and emergent properties of microbial communities: The power of synthetic ecology.

Humans have long relied on microbial communities to create products, produce energy, and treat waste. The microbiota residing within our bodies directly impacts our health, while the soil and rhizosphere microbiomes influence the productivity of our crops. However, the complexity and diversity of microbial communities make them challenging to study and difficult to develop into applications, as they often exhibit the emergence of unpredictable higher-order phenomena. Synthetic ecology aims at simplifying complexity by constituting synthetic or semi-natural microbial communities with reduced diversity that become easier to study and analyze. This strategy combines methodologies that simplify existing complex systems (top-down approach) or build the system from its constituent components (bottom-up approach). Simplified communities are studied to understand how interactions among populations shape the behavior of the community and to model and predict their response to external stimuli. By harnessing the potential of synthetic microbial communities through a multidisciplinary approach, we can advance knowledge of ecological concepts and address critical public health, agricultural, and environmental issues more effectively.

Sexual behavior and seminal characteristics of Brahman bulls in the Colombian tropical flooded savanna: effects of reproductive management systems and climatic periods.

The objective of this study was to evaluate the seminal traits and sexual behaviors of mature Brahman bulls in a multi-sire system during mating or resting seasons and different climatic periods of the year at the Colombian flooded savannas. Thirty-two Brahman bulls, suitable for reproduction, were used, which were subjected to breeding soundness evaluation, as well as the libido and service capacity tests. Such evaluations were compared among different seasons of the year in relation to the rainfall. Libido and service capacity tests were carried out in paddock for 12 continuous hours. Scrotal circumference and all seminal traits were not influenced by the mating or rest seasons, neither by the different climatic periods. However, libido and service capacity were significantly affected by the climatic periods, decreasing their expression during the intense rainfall season, and increasing during the transition period from summer to the onset of rains, which could be considered the appropriate time to establish mating seasons in this region. Furthermore, a high positive correlation was observed between libido and service capacity confirmed by a logistic model that animals with low libido have low probability of having high service capacity. In conclusion, although Brahman bulls are physiologically adapted to tropical regions, their expression of sexual behavior is markedly influenced by the weather. Hence, the use of libido test may serve as a good predictor of the service capacity, and a useful tool to improve the selection of sires.

Validation of a brief version of the Difficulties in Emotion Regulation Scale with a Spanish speaking population (DERS-S SF) / Validación de una versión breve de la Escala de Dificultades en la Regulación Emocional con población hispanohablante (DERS-S SF)

Abstract Emotion regulation refers to all the processes involved in adapting to relatively strong emotional episodes, and specifically to identifying, differentiating and monitoring intense emotional states in order to cope with stressful situations. Difficulties in regulating emotions are associated with problems such as depression, anxiety and maladaptive behaviors. The DERS (Difficulties in Emotion Regulation Scale) is the most complete tool for measuring difficulties with emotion regulation. Several brief versions of this scale in English are described in the literature, but no a brief Spanish version has been found. The purpose of this study is to validate a brief version of the DERS in Spanish. The DERS tool was used with a Spanish speaking population (n=351, inhabitants of Cartagena, Colombia, 56% were woman, Mage 39 years, SD = 14.98) who responded the 5-point Likert scale. The brief version (18 items) was validated using confirmatory factor analysis (X2 / df = 1.19, CFI= .99, TLI = .99, RMSEA=.02). However, neither the reliability nor the stability of the awareness dimension was confirmed. This point and other results are examined on the light of extant literature.

Resumen La regulación de las emociones se refiere a todos los procesos involucrados en la adaptación a episodios emocionales relativamente fuertes y, específicamente, en la identificación, diferenciación y seguimiento de estados emocionales intensos para hacer frente a situaciones estresantes. Las dificultades para regular las emociones están asociadas con problemas como la depresión, la ansiedad y los comportamientos desadaptativos. La Escala de Dificultades en la Regulación de las Emociones (DERS) es la herramienta más completa para medir las dificultades con la regulación de las emociones. En la literatura se describen varias versiones breves de esta escala en inglés, pero no se ha encontrado una versión breve en español. El propósito de este estudio es validar una versión breve del DERS en español. Se utilizó la herramienta DERS con una población hispanohablante (n = 351, habitantes de Cartagena, Colombia, 56% eran mujeres, Medad 39 años, DE = 14,98) que respondió la escala Likert de 5 puntos. La versión breve (18 ítems) se validó mediante análisis factorial confirmatorio (X2 / df = 1.19, CFI= .99, TLI = .99, RMSEA=.02). Sin embargo, no se confirmó ni la fiabilidad ni la estabilidad de la dimensión de conciencia. Este punto y otros resultados se examinan a la luz de la literatura existente.

Heterogeneous Liver on Research Ultrasound Identifies Children with Cystic Fibrosis at High Risk of Advanced Liver Disease: Interim Results of a Prospective Observational Case-Controlled Study.

OBJECTIVE: To assess if a heterogeneous pattern on research liver ultrasound examination can identify children at risk for advanced cystic fibrosis (CF) liver disease. STUDY DESIGN: Planned 4-year interim analysis of a 9-year multicenter, case-controlled cohort study (Prospective Study of Ultrasound to Predict Hepatic Cirrhosis in CF). Children with pancreatic insufficient CF aged 3-12 years without known cirrhosis, Burkholderia species infection, or short bowel syndrome underwent a screening research ultrasound examination. Participants with a heterogeneous liver ultrasound pattern were matched (by age, Pseudomonas infection status, and center) 1:2 with participants with a normal pattern. Clinical status and laboratory data were obtained annually and research ultrasound examinations biannually. The primary end point was the development of a nodular research ultrasound pattern, a surrogate for advanced CF liver disease. RESULTS: There were 722 participants who underwent screening research ultrasound examination, of which 65 were heterogeneous liver ultrasound pattern and 592 normal liver ultrasound pattern. The final cohort included 55 participants with a heterogeneous liver ultrasound pattern and 116 participants with a normal liver ultrasound pattern. All participants with at least 1 follow-up research ultrasound were included. There were no differences in age or sex between groups at entry. Alanine aminotransferase (42 ± 22 U/L vs 32 ± 19 U/L; P = .0033), gamma glutamyl transpeptidase (36 ± 34 U/L vs 15 ± 8 U/L; P < .001), and aspartate aminotransferase to platelet ratio index (0.7 ± 0.5 vs 0.4 ± 0.2; P < .0001) were higher in participants with a heterogeneous liver ultrasound pattern compared with participants with a normal liver ultrasound pattern. Participants with a heterogeneous liver ultrasound pattern had a 9.1-fold increased incidence (95% CI, 2.7-30.8; P = .0004) of nodular pattern vs a normal liver ultrasound pattern (23% in heterogeneous liver ultrasound pattern vs 2.6% in normal liver ultrasound pattern). CONCLUSIONS: Research liver ultrasound examinations can identify children with CF at increased risk for developing advanced CF liver disease.

Three-Way Interactions in an Artificial Community of Bacterial Strains Directly Isolated From the Environment and Their Effect on the System Population Dynamics.

This work is motivated by previous studies that have analyzed the population ecology of a collection of culturable thermoresistant bacteria, isolated from the Churince lagoon in Cuatro Cienegas, Mexico. In particular, it is aimed at testing a hypothesis from a modeling study, which states that antagonistic and sensitive bacteria co-exist thanks to resistant bacteria that protect sensitive ones by forming physical barriers. We selected three different bacterial strains from the referred collection: one antagonistic, one sensitive, and one resistant, and studied the population dynamics of mixed colonies. Our results show that, although the proposed protective mechanism does not work in this case, the resistant strain confers some kind of protection to sensitive bacteria. Further modeling and experimental results suggest that the presence of resistant bacteria indirectly improves the probability that patches of sensitive bacteria grow in a mixed colony. More precisely, our results suggest that by making antagonistic bacteria produce and secrete an antagonistic substance (with the concomitant metabolic cost and growth rate reduction), resistant bacteria increase the likelihood that sensitive bacteria locally outcompete antagonistic ones.

Bistable behaviour and medium-dependent post-translational regulation of the tryptophanase operon regulatory pathway in Echerichia coli.

The present work is aimed at studying the dynamic behaviour of the tryptopnanase (tna) operon, which encodes the proteins necessary to uptake and metabolise tryptophan to use it as a carbon source in the absence of glucose. To this end, we designed a micro-bioreactor capable of driving a bacterial culture to a stationary state. This allowed us to explore (at the single cell level) the tna operon steady-state dynamics under multiple culture conditions. Our experimental results suggest that the tna operon is bistable for a specific range of environmental tryptophan and glucose concentrations, and evidence that both reagents play a role on the activation of the enzyme in charge of metabolising tryptophan: tryptophanase (TnaA). Based on our experimental data and the already known regulatory mechanisms, we developed a mathematical model for the tna operon regulatory pathway. Our modelling results reinforce the claim that the tna operon is bistable, and further suggest that the activity of enzyme TnaA is regulated by the environmental levels of glucose and tryptophan via a common signalling pathway. Possible biological implications of our findings are further discussed.

Theoretical study on selectivity trends in (N-heterocyclic carbene)-Pd catalyzed mizoroki-heck reactions: Exploring density functionals methods and molecular models.

The regioselectivity of the NHC-Pd catalyzed Heck coupling reaction between phenyl bromide and styrene has been investigated using the density functional theory, wave-function (WF)-based methods and two different sizes of model ligands. In addition to the WF methods, the TPSS-D3, ω B97X-D, BP86-D3, and M06-L density functionals were reliable approaches to be applied, independently of the basis set. Moreover, the NCI analysis showed that weak interactions are important forces to be taken into account when exploring the regioselectivity of this reaction, mainly when a crowded NHC ligand is present. © 2017 Wiley Periodicals, Inc.

Variation in developmental patterns among elite wheat lines and relationships with yield, yield components and spike fertility.

Developmental patterns strongly influence spike fertility and grain number, which are primarily determined during the stem elongation period (i.e. time between terminal spikelet phase and anthesis). It has been proposed that the length of the stem elongation phase may, to an extent, affect grain number; thus it would be beneficial to identify genetic variation for the duration of this phase in elite germplasm. Variation in these developmental patterns was studied using 27 elite wheat lines in four experiments across three growing seasons. The results showed that the length of the stem elongation phase was (i) only slightly related to the period from seedling emergence to terminal spikelet, and (ii) more relevant than it for determining time to anthesis. Thus, phenological phases were largely independent and any particular time to anthesis may be reached with different combinations of component phases. Yield components were largely explained by fruiting efficiency of the elite lines used: the relationships were strongly positive and strongly negative with grain number and with grain weight, respectively. Although fruiting efficiency showed a positive trend with the duration of stem elongation that was not significant, a boundary function (which was highly significant) suggests that the length of this phase may impose an upper threshold for fruiting efficiency and grain number, and that maximum values of fruiting efficiency may require a relatively long stem elongation phase.

Análisis preliminar de un cuestionario de evaluación de la percepción social de la contaminación atmosférica / Preliminary analysis of a questionnaire for assessing the social perception of air pollution

Objetivo Analizar las propiedades psicométricas y la organización estructural de un cuestionario diseñado para evaluar la percepción social de la contaminación del aire y de sus riesgos para la salud en el Valle de Aburrá, área geográfica donde se ha identificado una problemática ambiental asociada a la polución. Métodos Estudio descriptivo en el que se diseñó y validó un cuestionario que recogía tres dimensiones de la percepción social de la contaminación del aire (socio-territorial, socio-cognitiva y comportamental) y algunas variables sociodemográficas. Tras el estudio piloto, las dimensiones de análisis fueron organizadas en 12 categorías, conformadas por 111 ítems con escalas tipo Likert de cuatro o cinco opciones de respuesta. El instrumento fue aplicado a una muestra no probabilística de 318 participantes, los cuales eran residentes de Medellín y del municipio de Girardota. Resultados Tras el análisis factorial exploratorio (rotación varimax), el cuestionario se redujo a 68 ítems que evalúan siete dimensiones de la percepción social de la contaminación atmosférica y de sus riesgos para la salud. La varianza total explicada es del 75 % y la confiabilidad alpha de Cronbach de la prueba fue 0,9. Discusión Las dimensiones encontradas permiten aproximarse a la organización estructural de la percepción social de la polución y de sus riesgos sanitarios en el contexto de estudio. Aunque algunas dimensiones socio-cognitivas y comportamentales fueron confirmadas, la dimensión socio-territorial y la implicación personal no se configuraron como componentes estructurales y requieren ser reelaboradas conceptualmente. Resulta necesario realizar un análisis estructural confirmatorio de las dimensiones del cuestionario.

Objective To analyze the psychometric properties and the structural organization of a questionnaire designed to assess the social perception of air pollution and its health risks in the Valle de Aburrá (Colombia), a geographical area where environmental problems associated with air pollution have been identified. Methods A descriptive study was carried out, in which a questionnaire was designed and validated to determine three dimensions of social perception of air pollution: the socio-territorial dimension, the socio-cognitive dimension and the behavioral dimension. Some socio-demographical variables were also included. After the pilot study, the dimensions of the analysis were organized into 12 categories, made up of 111 items with Likert scales of four or five response options. The instrument was applied to a non-random sample of 318 participants, who were residents of Medellin city and Girardota town. Results After exploratory factor analysis (varimax rotation), the questionnaire was reduced to 68 items assessing seven dimensions of social perception of air pollution and its health risks. The total variance explained is 75 %, and the overall Cronbach's alpha reliability was 0.9. Discussion The dimensions found allow us to develop an approach to the structural organization of the social perception of air pollution in the context of study. Although some socio-cognitive and behavioral dimensions were confirmed, the socio-territorial dimension and the personal involvement variable were not configured as structural components and, conceptually, they need to be reworked. Confirmatory structural analysis of the dimensions of the questionnaire is required.

[Preliminary analysis of a questionnaire for assessing the social perception of air pollution]. / Análisis preliminar de un cuestionario de evaluación de la percepción social de la contaminación atmosférica.

Objective To analyze the psychometric properties and the structural organization of a questionnaire designed to assess the social perception of air pollution and its health risks in the Valle de Aburrá (Colombia), a geographical area where environmental problems associated with air pollution have been identified. Methods A descriptive study was carried out, in which a questionnaire was designed and validated to determine three dimensions of social perception of air pollution: the socio-territorial dimension, the socio-cognitive dimension and the behavioral dimension. Some socio-demographical variables were also included. After the pilot study, the dimensions of the analysis were organized into 12 categories, made up of 111 items with Likert scales of four or five response options. The instrument was applied to a non-random sample of 318 participants, who were residents of Medellin city and Girardota town. Results After exploratory factor analysis (varimax rotation), the questionnaire was reduced to 68 items assessing seven dimensions of social perception of air pollution and its health risks. The total variance explained is 75 %, and the overall Cronbach's alpha reliability was 0.9. Discussion The dimensions found allow us to develop an approach to the structural organization of the social perception of air pollution in the context of study. Although some socio-cognitive and behavioral dimensions were confirmed, the socio-territorial dimension and the personal involvement variable were not configured as structural components and, conceptually, they need to be reworked. Confirmatory structural analysis of the dimensions of the questionnaire is required.

Characterization of guinea pig antibody responses to salivary proteins of Triatoma infestans for the development of a triatomine exposure marker.

BACKGROUND: Salivary proteins of Triatoma infestans elicit humoral immune responses in their vertebrate hosts. These immune responses indicate exposure to triatomines and thus can be a useful epidemiological tool to estimate triatomine infestation. In the present study, we analyzed antibody responses of guinea pigs to salivary antigens of different developmental stages of four T. infestans strains originating from domestic and/or peridomestic habitats in Argentina, Bolivia, Chile and Peru. We aimed to identify developmental stage- and strain-specific salivary antigens as potential markers of T. infestans exposure. METHODOLOGY AND PRINCIPAL FINDINGS: In SDS-PAGE analysis of salivary proteins of T. infestans the banding pattern differed between developmental stages and strains of triatomines. Phenograms constructed from the salivary profiles separated nymphal instars, especially the 5th instar, from adults. To analyze the influence of stage- and strain-specific differences in T. infestans saliva on the antibody response of guinea pigs, twenty-one guinea pigs were exposed to 5th instar nymphs and/or adults of different T. infestans strains. Western blot analyses using sera of exposed guinea pigs revealed stage- and strain-specific variations in the humoral response of animals. In total, 27 and 17 different salivary proteins reacted with guinea pig sera using IgG and IgM antibodies, respectively. Despite all variations of recognized salivary antigens, an antigen of 35 kDa reacted with sera of almost all challenged guinea pigs. CONCLUSION: Salivary antigens are increasingly considered as an epidemiological tool to measure exposure to hematophagous arthropods, but developmental stage- and strain-specific variations in the saliva composition and the respective differences of immunogenicity are often neglected. Thus, the development of a triatomine exposure marker for surveillance studies after triatomine control campaigns requires detailed investigations. Our study resulted in the identification of a potential antigen as useful marker of T. infestans exposure.

Representación social del medio ambiente y de la contaminación del aire: efecto de imbricación de dos objetos / Social representation of the environment and air pollution: effect of overlap of two objects

Las representaciones sociales son formas de pensamiento social, socialmente construidas y, en consecuencia, con una utilidad práctica. En el campo ambiental esta teoría ha demostrado un interés mayor en la comprensión de la base sociocognitiva subyacente a diferentes comportamientos y tomas de posición frente a este objeto de interés social. Este estudio parte de la hipótesis de que los diferentes objetos ambientales (agua, aire, riesgos ambientales, desarrollo sostenible), funcionan como una red de representaciones por el hecho de estar imbricados o anclados en la representación social del medio ambiente como marco normativo. 305 personas participaron al estudio, la mitad habitantes de una zona urbana expuesta a altos índices de polución (Medellín centro=expuestos) del aire y la otra mitad habitantes de una zona con índices negativos de polución (Municipio de Girardota=no expuestos). A través de diferentes análisis que buscan hacer hipótesis sobre la organización interna de las representaciones sociales del medio ambiente y de la contaminación del aire, se muestra empíricamente el rol central del componente "riesgo" en la primera. Un efecto de exposición a fuentes de polución del aire se evidencia para el segundo objeto (contaminación del aire), específicamente en la atribución de causas de la misma.

Social representations are forms of social thought, socially built and therefore with a practical use. In the environmental field, this theory has shown a greater interest in understanding the sociocognitive basis underlying to different behaviors and positions of that object of social interest. This study starts from the hypothesis that different environmental objects (water, air, environmental risks, sustainable development), work as a network of representations for being overlapped or anchored in the environment social representation as a policy framework. 305 people participated in the study, half of an urban population exposed to high levels of of the air pollution (Medellin center = exposed) and the other half living in an area with negative indices of the air pollution (Municipality Girardota= unexposed). Through various analyzes that identify the internal organization of environment and air pollution social representations, we try to empirically show the central role of the "risk" factor in the first one. An effect of exposure to air pollution sources is evidence for the second object (air pollution), specifically in the attribution of causes of pollution.

Evaluación de cinco protectores para la crioconservación de semen de Cachama Blanca (Piaractus brachypomus / Evaluation of five cryoprotectant for cryopreservation of Cachama Blanca (Piaractus brachypomus) milt

La Cachama Blanca (Piaractus brachypomus) es un pez de escama de los Llanos Orientales colombianos, considerada la especie íctica nativa más importante de la acuicultura colombiana. La utilización de semen criopreservado para la reproducción de esta especie puede traer grandes posibilidades de mejoramiento genético; sin embargo, a pesar que han sido realizados esfuerzos para lograr la crioconservación de semen, los índices de fertilidad aún son inferiores a los observadosutilizando semen fresco. El objetivo del presente trabajo fue evaluar la calidad y fertilidad de semende cachama blanca, crioconservado con cinco diferentes sustancias crioprotectoras: glicerol (GLY), dimetil sulfóxido (DMSO), metanol (MET), propilen glicol (PPG) y etilen glicol (ETG). Se utilizó semen de 15 reproductores adultos, 4.8 ± 1.1 kg de peso corporal, tratados con 4.0 mg/kg de extracto de hipófisis de carpa (EPC) vía IM. El semen fue recolectado mediante estrujamiento, recibido en tubos graduados y mantenido a temperatura ambiente (26°C) hasta su evaluación. Los resultados están expresados en promedio ± error estándar. Antes de la dilución la movilidad masal fue de 92 ± 1 por ciento y la concentración de 17.7 x 109 ± 1.8 x109 espermatozoides por mL. Se utilizaron dos diluyentes: D1 (glucosa [C6H12O6] 5,5 g; yema de huevo 7.0 mL y agua destilada c.s.p. 100 mL) y D2 (leche enteraen polvo 15 g, agua destilada c.s.p. 100 mL). Para D1 se utilizó como crioprotector 5 por ciento (D1-DMSO 5o D1-GLY 5), 10 por ciento (D1-DMSO 10 o D1-GLY 10) o 15 por ciento (D1-DMSO 15 o D1-GLY 15) de dimetil sulfóxido o de glicerol, respectivamente. Para el D2, 5 por ciento (D2-MET 5, D2-PPG 5 o D2-ETG 5), 10 por ciento (D2-MET 10, D2-PPG 10 o D2-ETG 10) o 15 por ciento (D2-MET 15, D2-PPG 15 o D2-ETG 15) de metanol, propilen glicol o etilen glicol, respectivamente. Los mayores porcentajes de movilidad masal posdescongelación fueron observados cuando se utilizó D2-PPG 5 (64±2.4 por ciento) y D2-MET 10....

Evaluación de la eficacia y seguridad entre el parto vaginal asistido con fórceps y el extractor de vacío / Efficay and security evaluation between the vaginal assisted delivery with vacuum extractor and forceps

Se realizó estudio comparativo, prospectivo, aleatorizado para valorar eficacia y seguridad entre parto vaginal asistido con fórceps y parto asistido con extracto de vacío. Se designó un grupo control de pacientes primigestas con parto vaginal normal. Los criterios de aplicación de ambos instrumentos fueron aceptados por el Colegio Americano de Ginecólogos y Obstetras para el parto operatorio. Se valoró diferencia en cuanto a indicación de instrumentación, trauma obstétrico (cefalohematomas, hematomas subgaleales, hemorragias intraventriculares, hemorragias retinianas, etcétera) y características generales de pacientes. Se incluyeron un total de 210 pacientes, las cuales fueron distribuidas en 3 grupos de 70 pacientes cada uno. El primero, sometido a aplicación de extractor de vacío, el segundo a fórceps y tercero como grupo control. Entre los resultados encontramos que las principales indicaciones para parto operatorio fueron cesárea previa (29 por ciento), segundo periodo prolongado (22 por ciento), embarazo postérmino (17 por ciento) y trastornos hipertensivos del embarazo (16 por ciento). No hubo diferencia estadísticamente significativa cuando se compararon características generales de pacientes de los 3 grupos. En cuanto las complicaciones encontramos que en el grupo de extractor de vacío se presentaron 6 cefalohematomas (8.5 por ciento), dos productos con laceración en piel cabelluda (2.8 por ciento) y edema cerebral en cuatro productos (5.7 por ciento). En el grupo de fórceps se observaron dos recién nacidos con cefalohematomas (2.8 por ciento), siete productos con edema cerebral (10 por ciento) y laceraciones en piel cabelluda en cuatro productos (6 por ciento). En el grupo control se encontró un producto con cefalohematoma (1.4 por ciento), edema cerebral en cuatro productos (5.7 por ciento) no hubo laceraciones en piel cabelluda. En ninguno de los 3 grupos se encontraron hemorragias intraventriculares o retinianas. Tampoco existió diferencia estadísticamente significativa al comparar grupo de fórceps con el extractor de vacío referente a complicaciones. Conclusiones. Encontramos que ambos instrumentos son seguros y eficaces en manejo operatorio del segundo periodo del trabajo de parto, esto siempre y cuando se utilicen con apego estricto a criterios de aplicación en manos experimentadas. El parto instrumentado se asocia a un incremento en lesiones del canal del parto y abrasiones en el producto, sin aumento significativo en la mortalidad.