Indole modifies the central carbon flux in the anaerobic metabolism of Escherichia coli: application to the production of hydrogen and other metabolites.

Indole is a bicyclic signaling molecule with effects on both eukaryotic and prokaryotic cells. The majority of studies of indole action have been performed with bacteria cultured under aerobic conditions and little information is available about its effects under anaerobic conditions. Here the effect of the indole on anaerobic metabolism of Escherichia coli WDHL was studied. Indole in the range 0.5-8mM was added to the culture medium and cell growth, hydrogen and metabolite production were compared to cultures lacking indole. Results showed that while 8mM indole abolished growth completely, 4mM indole had a partial bacteriostatic effect and the maximum optical density of the culture decreased by 44% compared to the control cultures. In addition, 4mM indole had an important effect on anaerobic metabolism. Hydrogen production increased from 650±115 to 1137±343mL H2/L, and hydrogen yield increased from 0.45±0.1 to 0.94±0.34mol H2/mol glucose, compared to the control culture. Carbon flux was also affected and the composition of the final by-products changed. Lactate (41mM) was the main metabolite in the control cultures, whereas ethanol (56.2mM) and acetate (41.2mM) were the main metabolites in the cultures with 2mM indole. We conclude that the supplementation of E. coli cultures with exogenous indole is a simple and novel strategy to improve the production of hydrogen as well as other metabolites such as ethanol used as biofuels.Partial financial support from CONACyT Grant Pro Nal 247498, SENER-Cemie Bio249564, and CONACyT sabbatical fellowship 259644.This is the author accepted manuscript. The final version is available from Elsevier via https://doi.org/10.1016/j.nbt.2016.09.00

Trading Off Aircraft Fuel Burn and NOx Emissions for Optimal Climate Policy

Aviation emits pollutants that affect climate, including CO2 and NOx; NOx indirectly so, through the formation of tropospheric ozone and reduction of ambient methane. To improve the fuel performance of engines, combustor temperatures and pressures often increase, increasing NOx emissions. Conversely, combustor modifications to reduce NOx may increase CO2. Hence, a technology tradeoff exists, which also translates to a tradeoff between short lived climate forcers and a long-lived greenhouse gas, CO2. Moreover, the NOx-O3-CH4 system responds in a non-linear manner, according to both aviation emissions and background NOx. A simple climate model was modified to incorporate non-linearities parameterized from a complex chemistry model. Case studies showed that for a scenario of a 20% reduction in NOx emissions the consequential CO2 penalty of 2% actually increased the total radiative forcing (RF). For a 2% fuel penalty, NOx emissions needed to be reduced by >43% to realize an overall benefit. Conversely, to ensure the fuel penalty for a 20% NOx emission reduction did not increase overall forcing, a 0.5% increase in CO2 was found to be the ‘break even’ point. The timescales of the climate effects of NOx and CO2 are quite different, necessitating careful analysis of proposed emissions tradeoffs

A population-based controlled experiment assessing the epidemiological impact of digital contact tracing

While Digital contact tracing (DCT) has been argued to be a valuable complement to manual tracing in the containment of COVID-19, no empirical evidence of its effectiveness is available to date. Here, we report the results of a 4-week population-based controlled experiment that took place in La Gomera (Canary Islands, Spain) between June and July 2020, where we assessed the epidemiological impact of the Spanish DCT app Radar Covid. After a substantial communication campaign, we estimate that at least 33% of the population adopted the technology and further showed relatively high adherence and compliance as well as a quick turnaround time. The app detects about 6.3 close-contacts per primary simulated infection, a significant percentage being contacts with strangers, although the spontaneous follow-up rate of these notified cases is low. Overall, these results provide experimental evidence of the potential usefulness of DCT during an epidemic outbreak in a real population

A parabolic solar collector for harnessing solar energy in Bucaramanga, Colombia

In this work, a solar energy collection system based on a parabolic solar collector adjusted to the conditions and availability of energy was designed to examine this type of collection device and evaluate the energy potential when installed in an educational institution. To do this, data from the historical series of solar radiation compiled by the POWER project (Prediction of Worldwide Energy Resources) were analyzed and compared with data from the Institute of Hydrology, Meteorology and Environmental Studies in Colombia (IDEAM)

First month prednisone dose predicts prednisone burden during the following 11 months: An observational study from the RELES cohort

Aim: To study the influence of prednisone dose during the first month after systemic lupus erythematosus (SLE) diagnosis (prednisone-1) on glucocorticoid burden during the subsequent 11 months (prednisone-2–12). Methods: 223 patients from the Registro Español de Lupus Eritematoso Sistémico inception cohort were studied. The cumulative dose of prednisone-1 and prednisone-2–12 were calculated and recoded into a four-level categorical variable: no prednisone, low dose (up to 7.5 mg/day), medium dose (up to 30 mg/day) and high dose (over 30 mg/day). The association between the cumulative prednisone-1 and prednisone-2–12 doses was tested. We analysed whether the four-level prednisone-1 categorical variable was an independent predictor of an average dose >7.5 mg/day of prednisone-2–12. Adjusting variables included age, immunosuppressives, antimalarials, methyl-prednisolone pulses, lupus nephritis and baseline SLE Disease Activity Index (SLEDAI). Results: Within the first month, 113 patients (51%) did not receive any prednisone, 24 patients (11%) received average low doses, 46 patients (21%) received medium doses and 40 patients (18%) received high doses. There was a strong association between prednisone-1 and prednisone-2–12 dose categories (p7.5 mg/day, while patients receiving low-dose prednisone-1 were not (adjusted OR 1.4, 95% CI 0. 0.38 to 5.2). If the analysis was restricted to the 158 patients with a baseline SLEDAI of =6, the model did not change. Conclusion: The dose of prednisone during the first month after the diagnosis of SLE is an independent predictor of prednisone burden during the following 11 months

Tomography of Galactic star-forming regions and spiral arms with the Square Kilometer Array

© 2014 Copyright owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike Licence https://creativecommons.org/licenses/by-nc-sa/3.0/us/. Published by Proceedings of Science http://pos.sissa.it/Very Long Baseline Interferometry (VLBI) at radio wavelengths can provide astrometry accurate to 10 micro-arcseconds or better (i.e. better than the target GAIA accuracy) without being limited by dust obscuration. This means that unlike GAIA, VLBI can be applied to star-forming regions independently of their internal and line-of-sight extinction. Low-mass young stellar objects (particularly T Tauri stars) are often non-thermal compact radio emitters, ideal for astrometric VLBI radio continuum experiments. Existing observations for nearby regions (e.g. Taurus, Ophiuchus, or Orion) demonstrate that VLBI astrometry of such active T Tauri stars enables the reconstruction of both the regions' 3D structure (through parallax measurements) and their internal kinematics (through proper motions, combined with radial velocities). The extraordinary sensitivity of the SKA telescope will enable similar "tomographic mappings" to be extended to regions located several kpc from Earth, in particular to nearby spiral arm segments. This will have important implications for Galactic science, galactic dynamics and spiral structure theories

Psychometric evidence of a brief measure of resilience in non-institutionalized Peruvian older adults

Resilience is understood as the domain of personal resources and contextual factors that allow for a successful coping and enhance positive adaptation to the different stressors during the lifespan, thereby being important for a healthy and successful aging. Nowadays, several brief instruments have been developed to measure resilience, such as the Brief Resilient Coping Scale (BRCS), an instrument that measures the ability of people to confront stress in an adaptive way. In this vein, the study provides evidence of the validity and reliability of the BRCS in non-institutionalized older adults in Peru. Two hundred thirty-six elderly people of both genders, 78.4% women and 21.6% men, with a mean age of 72.8 years (SD= 6.90), who answered the Spanish version of the BRCS and other scales to measure satisfaction with life, humor as coping, and depression. Confirmatory factor analysis corroborates the one-dimensional structure of the BRCS. The coefficients of internal consistency, Chronbach's alpha and omega, indicated an adequate reliability of the BRCS. Both the adjustment indices of the model and the values of the coefficients of reliability were higher compared to those reported in the literature. The BRCS showed positive and significant correlations with satisfaction with life and humor as coping (p < .01). Likewise, negative and significant correlations were observed with depression (p < .01). The results show that the BRCS has proved valid and reliable, supporting its use as a short measure of resilience in older Peruvians.La resiliencia es comprendida como el dominio de recursos personales y factores contextuales que permiten un afrontamiento exitoso y el logro de una adaptación positiva ante los diferentes estresores que aparecen a lo largo de la vida, siendo así importante dentro del proceso de envejecimiento saludable y exitoso. En la actualidad se han desarrollado instrumentos breves para la medición de la resiliencia como la escala breve de resiliencia (BRCS - Brief Resilient Coping Scale) que evalúa la capacidad de los individuos para hacer frente al estrés de manera adaptativa. En este sentido, el estudio ofrece evidencia de validez y fiabilidad de la BRCS en adultos mayores no institucionalizados peruanos. Se contó con la participación de 236 adultos mayores con una edad promedio de 72.8 años (DT = 6.90) de los cuales el 78.4% eran mujeres y el 21.6% hombres, quienes respondieron la versión en español del BRCS y otras escalas para medir la satisfacción con la vida, humor como afrontamiento y depresión. Mediante el análisis factorial confirmatorio se corrobora la estructura unidimensional de la BRCS. Los coeficientes de consistencia interna alfa de Cronbach y omega indicaron una adecuada fiabilidad de la BRCS. Tanto los índices de ajuste del modelo como los valores de los coeficientes de fiabilidad fueron mejores en comparación con los reportados en la literatura. La BRCS mostró una correlación positiva significativa con la satisfacción con la vida y el humor como afrontamiento (p < .01). Asimismo, se observó una correlación negativa significativa con depresión (p < .01). Los resultados muestran que la BRCS cuenta con evidencias de validez y fiabilidad que avala su empleo como medida breve de la resiliencia en adultos mayores peruanos

High serum levels of tissue inhibitor of matrix metalloproteinase-1 during the first week of a malignant middle cerebral artery infarction in non-surviving patients

Background: Higher circulating levels of tissue inhibitor of matrix metalloproteinases (TIMP)-1 early after ischemic stroke have been associated with lower survival. The objectives of this study were to determine serum TIMP-1 levels during the first week of a severe cerebral infarction in surviving and non-surviving patients, and whether those levels during the first week could be used as a mortality biomarker for these patients. Methods: We included patients with severe malignant middle cerebral artery infarction (MMCAI) defined as computer tomography showing ischaemic changes in more than 50% of the middle cerebral artery territory and Glasgow Coma Scale (GCS) ≤ 8. We measured serum levels of matrix metalloproteinases (MMP)-9 and TIMP-1. End-point study was 30-day mortality. Results: We found higher TIMP-1 concentrations at days 1 (p < 0.001), 4 (p = 0.001), and 8 (p = 0.03) of MMCAI in nonurviving (n = 34) than in surviving (n = 34) patients. We found lower serum MMP-9 concentrations at day 1 (p = 0.03) of MMCAI and no significant differences at days 4 and 8. ROC curve analysis of TIMP-1 concentrations performed at days 1, 4, and 8 of MMCAI showed an area under curve to predict 30-day mortality of 81% (p < 0.001), 80% (p < 0.001) and 72% (p = 0.07) respectively. Conclusions: The new findings of our study were that non-surviving MMCAI patients showed higher serum TIMP-1 levels during the first week of MMCAI that surviving patients, and those levels during the first week of MMCAI could be used as mortality biomarkers