Impact of Metabolomics in Symbiosis Research

In symbiotic associations, there is a constant molecular complexity that allows establishment and maintenance of the relationship. Metabolomic profiles have enabled researchers to explain symbiotic associations in terms of their underlying molecules and interactions between the symbiotic partners. In this review, we have selected studies on symbioses as examples that have helped to explain the metabolic integration of bacterial symbionts and their hosts in an effort to understand the molecular fingerprint of animal-microbial symbioses

Effect of moisture on leaf litter decomposition and its contribution to soil respiration in a temperate forest

The degree to which increased soil respiration rates following wetting is caused by plant (autotrophic) versus microbial (heterotrophic) processes, is still largely uninvestigated. Incubation studies suggest microbial processes play a role but it remains unclear whether there is a stimulation of the microbial population as a whole or an increase in the importance of specific substrates that become available with wetting of the soil. We took advantage of an ongoing manipulation of leaf litter <sup>14</sup>C contents at the Oak Ridge Reservation, Oak Ridge, Tennessee, to (1) determine the degree to which an increase in soil respiration rates that accompanied wetting of litter and soil, following a short period of drought, could be explained by heterotrophic contributions; and (2) investigate the potential causes of increased heterotrophic respiration in incubated litter and 0–5 cm mineral soil. The contribution of leaf litter decomposition increased from 6 ± 3 mg C m<sup>−2</sup> hr<sup>−1</sup> during a transient drought, to 63 ± 18 mg C m<sup>−2</sup> hr<sup>−1</sup> immediately after water addition, corresponding to an increase in the contribution to soil respiration from 5 ± 2% to 37 ± 8%. The increased relative contribution was sufficient to explain all of the observed increase in soil respiration for this one wetting event in the late growing season. Temperature (13°C versus 25°C) and moisture (dry versus field capacity) conditions did not change the relative contributions of different decomposition substrates in incubations, suggesting that more slowly cycling C has at least the same sensitivity to decomposition as faster cycling organic C at the temperature and moisture conditions studied

Temporal evolution of a driven optomechanical system in the strong coupling regime

We obtain a time-evolution operator for a forced optomechanical quantum system using Lie algebraic methods when the normalized coupling between the electromagnetic field and a mechanical oscillator, $G/\omega_m$, is not negligible compared to one. Due to the forcing term, the interaction picture Hamiltonian contains the number operator in the exponents, and in order to deal with it, we approximate these exponentials by their average values taken between initial coherent states. Our approximation is justified when we compare our results with the numerical solution of the number of photons, phonons, Mandel parameter, and the Wigner function, showing an excellent agreement.Comment: 21 pages, 11 figure

Expression of AdipoR1 and AdipoR2 Receptors as Leptin-Breast Cancer regulation mechanisms

: La obesidad es considerada como uno de los principales factores de riesgo implicados en el desarrollo del cáncer de mama y se ha documentado el papel que juega el tejido adiposo a través de Leptina y Adiponectina. El estudio de estas proteínas ha determinado su importancia en el desarrollo y progreso del cáncer de mama, pero muy pocos son los que han estudiado a AdipoR1 y AdipoR2 y la influencia de la Leptina sobre ellos. Se planteó el analizó la expresión de AdipoR1 y AdipoR2 modulada por concentraciones diferenciales de Leptina en un modelo de obesidad asociado a cáncer de mama en líneas celulares, utilizando sondas TaqMan®, mediado por concentraciones diferenciales de Leptina en líneas celulares. Seguido se llevó a cabo la extracción de RNA, obtención de cDNA (Retrotranscripción) y PCR en tiempo real. Se caracterizó cada línea celular por medio de Inmunohistoquímica. Concluyendo con base en los resultados que la concentración de normo-peso (10ng/mL) de leptina generó un incremento de la expresión de ambos receptores de adiponectina.The development of breast cancer is influenced by the adipose tissue through the proteins leptin and adiponectin. However, there is little research concerning AdipoR1 and AdipoR2 receptors and the influence of leptin over them. The objective of this work was to analyze the expression of AdipoR1 and AdipoR2, modulated by differential concentrations of leptin in an obesity model (10ng/mL, 100ng/mL, and 1000ng/mL) associated with breast cancer in MCF-7 and HCC1937 cell lines. Each cell was characterized through immunohistochemistry, and the expression of AdipoR1 and AdipoR2 was analyzed by PCR in real time using TaqMan® probes. Leptin induced an increase in cell population of MCF-7 (23.8%, 10ng/m, 48 h) and HCC1937 (17.24%, 1000ng/mL, 72 h). In MCF-7, the expression of AdipoR1 decreased (3.81%, 1000ng/Ml) and the expression of AdipoR2 increased by 13.74 times (10ng/mL) with regard to the control. In HCC1937, the expression of AdipoR1 decreases by 86.28% (10ng/mL), as well as the expression of AdipoR1 and AdipoR2 mRNA

An 1800-year oxygen-isotope record of short- and long-term hydroclimate variability in the northern neotropics from a Jamaican marl lake

Hydroclimate variability on multi-decadal timescales has been a prominent feature of the circum-Caribbean region over the common era, with marked dry intervals noted in particular for the period 800–950 CE coinciding with the Terminal Classic Period (the so-called Terminal Classic Drought: TCD) in Mesoamerica, and with the Little Ice Age from about 1500 to 1800 CE, linked to complex ocean-atmosphere interactions. Previous compilations of palaeoclimate reconstructions have revealed a clear precipitation dipole between northern and southern Mesoamerica over the common era, which is consistent with meteorological data and modelling experiments. However, patterns of variability elsewhere within the region are less well understood, although palaeoclimate records do point to spatial complexity. Here, we present a ∼sub-decadal-scale lake-sediment hydroclimate reconstruction based on ostracod-shell stable isotopes from Wallywash Great Pond, Jamaica, covering the past ∼1800 years, which fills a spatial gap in records for the region. Variations in δ18O values at this site are a proxy for changes in effective moisture and they reveal a marked wet phase over the Terminal Classic Period (TCP), suggesting that the precipitation dipole over northern and southern Mesoamerica may have an east to west component. This is supported by some previous studies, although additional sites are required from strategic localities within the region to confirm this. The Little Ice Age interval at Wallywash is drier than the TCP, although the signal is less clear than at some sites within the wider region, suggesting that regional complexity in hydroclimate has characterised this interval as well

Speciation in Behavioral Space for Evolutionary Robotics

International audienceIn Evolutionary Robotics, population-based evolutionary computation is used to design robot neurocontrollers that produce behaviors which allow the robot to fulfill a user-defined task. However, the standard approach is to use canonical evolutionary algorithms, where the search tends to make the evolving population converge towards a single behavioral solution, even if the high-level task could be accomplished by structurally different behaviors. In this work, we present an approach that preserves behavioral diversity within the population in order to produce a diverse set of structurally different behaviors that the robot can use. In order to achieve this, we employ the concept of speciation, where the population is dynamically subdivided into sub-groups, or species, each one characterized by a particular behavioral structure that all individuals within that species share. Speciation is achieved by describing each neurocontroller using a representations that we call a behavior signature, these are descriptors that characterize the traversed path of the robot within the environment. Behavior signatures are coded using character strings, this allows us to compare them using a string similarity measure, and three measures are tested. The proposed behavior-based speciation is compared with canonical evolution and a method that speciates based on network topology. Experimental tests were carried out using two robot tasks (navigation and homing behavior), several training environments, and two different robots (Khepera and Pioneer), both real and simulated. Results indicate that behavior-based speciation increases the diversity of the behaviors based on their structure, without sacrificing performance. Moreover, the evolved controllers exhibit good robustness when the robot is placed within environments that were not used during training. In conclusion, the speciation method presented in this work allows an evolutionary algorithm to produce several robot behaviors that are structurally different but all are able to solve the same robot task

Antibacterial activity of mexican oregano essential oil (Lippia berlandieri) against the phytopathogenic bacterium Xanthomonas euvesicatoria

Xanthomonas euvesicatoria causes bacterial spot disease in leaves, roots, fruits and stems of pepper plants. Identification of this phytopathogen in jalapeno seeds from Delicias, Chihuahua, Mexico and diseased plants from New Mexico, USA, was carried out by isolation on semiselective media, pathogenicity assays and biochemical tests. Mexican oregano (Lippia berlandieri) essential oil was tested in vitro against Xanthomonas euvesicatoria. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were performed and the oil showed an inhibition of bacterial growth in concentrations of 0.01 mg/ml and a bactericidal effect in concentrations of 0.05 mg/ml. Oregano essential oil is reported to have antimicrobial activities due to the effect of high content of carvacrol. Oregano oil had an MIC that was 10 times lower compared to pure carvacrol, since carvacrol content, measured by gas chromatography/mass spectrometry (GC/ MS) was only 30%. The antimicrobial effect in vivo was tested using a randomized complete block design model in a greenhouse. Disease severity, xanthomonad incidence as well as chlorophyll indices were calculated showing a strong inhibition of the disease, when seeds or foliage were treated with oregano oil. These results demonstrate the current commonality of xanthomonad pathogens on both sides of the Mexican-American border, and that oregano oil has potent antibacterial activity. Resumen Xanthomonas euvesicatoria es la bacteria agente causal de la marchitez bacteriana en hojas, raíces y frutos de chile jalapeño. Se realizó la identificación de este patógeno en las semillas de chile jalapeño provenientes de Delicias, Chihuahua, México y plantas enfermas provenientes del estado de Nuevo Mexico, EUA; a través de cultivo en medios semi-selectivos, ensayos de patogenicidad y pruebas bioquímicas. El aceite esencial del orégano mexicano (Lippia berlandieri) fue probado in vitro contra Xanthomonas euvesicatoria. Pruebas de concentración mínima inhibitoria (CMI) y concentración mínima bactericida (CMB) fueron determinadas y el aceite mostró una inhibición de crecimiento a concentraciones de 0.01 mg/ml y un efecto bactericida a concentraciones de 0.05 mg/ ml. El aceite esencial de orégano muestra actividades antibacterianas gracias al efecto de la alta concentración de carvacrol. El aceite de orégano mostró una CMI que fue 10 veces menor en comparación con el efecto de carvacrol puro, ya que la concentración determinada en el aceite por medio de cromatografía de gases/espectrometría de masas (GC/MS) fue de 30% de carvacrol. El efecto antibacteriano in vivo fue probado utilizando un diseño de bloques completos al azar en un invernadero. La severidad e incidencia de la enfermedad, así como los índices de clorofila, fueron calculados mostrando una inhibición de la enfermedad cuando las semillas u hojas de las plantas de chile se trataron con el aceite de orégano. Estos resultados demuestran la problemática de la bacteria Xanthomonas en las fronteras México-Americanas y que el aceite esencial de orégano ejerce una acción antibacteriana. Palabras clave: marchitez bacteriana, concentración mínima inhibitoria, Carvacrol

Extracting Space Situational Awareness Events from News Text

Space situational awareness typically makes use of physical measurements from radar, telescopes, and other assets to monitor satellites and other spacecraft for operational, navigational, and defense purposes. In this work we explore using textual input for the space situational awareness task. We construct a corpus of 48.5k news articles spanning all known active satellites between 2009 and 2020. Using a dependency-rule-based extraction system designed to target three high-impact events - spacecraft launches, failures, and decommissionings, we identify 1,787 space-event sentences that are then annotated by humans with 15.9k labels for event slots. We empirically demonstrate a state-of-the-art neural extraction system achieves an overall F1 between 53 and 91 per slot for event extraction in this low-resource, high-impact domain. © European Language Resources Association (ELRA), licensed under CC-BY-NC-4.0.Open access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]