Electro bioremediación de fondos de tanques petroleros

The aim of this study was to use a voltage difference to increase the bioavailability of hydrocarbons presents in the bottom sediments of oil tank. This experiment was carried out in a glass cuba with three compartment communicated by phosphate-buffered saline bridges that allowed the voltage difference and maintained the soil pH at optimum values for bacterial life. After several 4 days the bioavailability of hydrocarbon was increased by 18.8% in the area near the anode and 5.5% in the area near the cathode.El objetivo de este estudio fue utilizar una diferencia de voltaje para aumentar la biodisponibilidad de los hidrocarburos presentes en los sedimentos del fondo de tanques petroleros. El experimento se realizó en una cuba de vidrio con tres compartimento comunicadas por puentes salinos de buffer fosfato que permitieron la diferencia de voltaje y mantener el pH del suelo en valores óptimos para la vida bacteriana. Después de 4 días se aumento en un 18.8% los hidrocarburos biodisponibles en la zona cercana al ánodo y 5.5% en la zona cercana al cátodo

Cambios en las comunidades bacterianas de suelo luego de una contaminación con hexadecano

This paper reports on changes in the soil bacterial community from a petroleum zone of Argentina. Changes were observed in a microcosm test which was subject to contamination with hexadecane. The determination of hydrocarbons and bacterial counts were performed weekly. Changes in bacterial diversity were determined by the analysis of membrane fatty acids (FAMEs), identified and quantified by gas chromatography using according to MIDI parameters. It was observed that contamination with hexadecane cause a disturbance in the soil leading to a change in the bacterial community structure.El presente trabajo informa sobre los cambios en la comunidad bacteriana de un suelo proveniente de una zona hidrocarburífera de Argentina. Los cambios se observaron en un ensayo de microcosmo el cual fue sometido a contaminación con hexadecano. La determinacion de hidrocarburos y los recuentos bacterianos fueron realizados semanalmente. Los cambios en la diversidad bacteriana se determinaron por la el análisis de los ácidos grasos de membrana (FAMEs); identificándose y cuantificándose por cromatografía gaseosa utilizando los parámetros según MIDI. Se observó que la contaminación con hexadecano causa un disturbio en el suelo que conduce a un cambio en la estructura de la comunidad bacteriana

TOI-733 b -- a planet in the small-planet radius valley orbiting a Sun-like star

We report the discovery of a hot ($T_{\rm eq}$ $\approx$ 1055 K) planet in the small planet radius valley transiting the Sun-like star TOI-733, as part of the KESPRINT follow-up program of TESS planets carried out with the HARPS spectrograph. TESS photometry from sectors 9 and 36 yields an orbital period of $P_{\rm orb}$ = $4.884765 _{ - 2.4e-5 } ^ { + 1.9e-5 }$ days and a radius of $R_{\mathrm{p}}$ = $1.992 _{ - 0.090 } ^ { + 0.085 }$ $R_{\oplus}$. Multi-dimensional Gaussian process modelling of the radial velocity measurements from HARPS and activity indicators, gives a semi-amplitude of $K$ = $2.23 \pm 0.26$ m s$^{-1}$, translating into a planet mass of $M_{\mathrm{p}}$ = $5.72 _{ - 0.68 } ^ { + 0.70 }$ $M_{\oplus}$. These parameters imply that the planet is of moderate density ($\rho_\mathrm{p}$ = $3.98 _{ - 0.66 } ^ { + 0.77 }$ g cm$^{-3}$) and place it in the transition region between rocky and volatile-rich planets with H/He-dominated envelopes on the mass-radius diagram. Combining these with stellar parameters and abundances, we calculate planet interior and atmosphere models, which in turn suggest that TOI-733 b has a volatile-enriched, most likely secondary outer envelope, and may represent a highly irradiated ocean world - one of only a few such planets around G-type stars that are well-characterised.Comment: Accepted for publication in A&

TOI-2196 b : Rare planet in the hot Neptune desert transiting a G-type star

Funding: C.M.P., M.F., I.G., and J.K. gratefully acknowledge the support of the Swedish National Space Agency (DNR 65/19, 174/18, 177/19, 2020-00104). L.M.S and D.G. gratefully acknowledge financial support from the CRT foundation under Grant No. 2018.2323 “Gaseous or rocky? Unveiling the nature of small worlds”. P.K. acknowledges support from grant LTT-20015. E.G. acknowledge the support of the Thüringer Ministerium für Wirtschaft, Wissenschaft und Digitale Gesellschaft. J.S.J. gratefully acknowledges support by FONDECYT grant 1201371 and from the ANID BASAL projects ACE210002 and FB210003. H.J.D. acknowledges support from the Spanish Research Agency of the Ministry of Science and Innovation (AEI-MICINN) under grant PID2019-107061GBC66, DOI: 10.13039/501100011033. D.D. acknowledges support from the TESS Guest Investigator Program grants 80NSSC21K0108 and 80NSSC22K0185. M.E. acknowledges the support of the DFG priority program SPP 1992 "Exploring the Diversity of Extrasolar Planets" (HA 3279/12-1). K.W.F.L. was supported by Deutsche Forschungsgemeinschaft grants RA714/14-1 within the DFG Schwerpunkt SPP 1992, Exploring the Diversity of Extrasolar Planets. N.N. acknowledges support from JSPS KAKENHI Grant Number JP18H05439, JST CREST Grant Number JPMJCR1761. M.S.I.P. is funded by NSF.The hot Neptune desert is a region hosting a small number of short-period Neptunes in the radius-instellation diagram. Highly irradiated planets are usually either small (R ≲ 2 R⊕) and rocky or they are gas giants with radii of ≳1 RJ. Here, we report on the intermediate-sized planet TOI-2196 b (TIC 372172128.01) on a 1.2 day orbit around a G-type star (V = 12.0, [Fe/H] = 0.14 dex) discovered by the Transiting Exoplanet Survey Satellite in sector 27. We collected 41 radial velocity measurements with the HARPS spectrograph to confirm the planetary nature of the transit signal and to determine the mass. The radius of TOI-2196 b is 3.51 ± 0.15 R⊕, which, combined with the mass of 26.0 ± 1.3 M⊕, results in a bulk density of 3.31−0.43+0.51 g cm−3. Hence, the radius implies that this planet is a sub-Neptune, although the density is twice than that of Neptune. A significant trend in the HARPS radial velocity measurements points to the presence of a distant companion with a lower limit on the period and mass of 220 days and 0.65 MJ, respectively, assuming zero eccentricity. The short period of planet b implies a high equilibrium temperature of 1860 ± 20 K, for zero albedo and isotropic emission. This places the planet in the hot Neptune desert, joining a group of very few planets in this parameter space discovered in recent years. These planets suggest that the hot Neptune desert may be divided in two parts for planets with equilibrium temperatures of ≳1800 K: a hot sub-Neptune desert devoid of planets with radii of ≈ 1.8−3 R⊕ and a sub-Jovian desert for radii of ≈5−12 R⊕. More planets in this parameter space are needed to further investigate this finding. Planetary interior structure models of TOI-2196 b are consistent with a H/He atmosphere mass fraction between 0.4% and 3%, with a mean value of 0.7% on top of a rocky interior. We estimated the amount of mass this planet might have lost at a young age and we find that while the mass loss could have been significant, the planet had not changed in terms of character: it was born as a small volatile-rich planet and it remains one at present.Publisher PDFPeer reviewe

Impact of COVID-19 on cardiovascular testing in the United States versus the rest of the world

Objectives: This study sought to quantify and compare the decline in volumes of cardiovascular procedures between the United States and non-US institutions during the early phase of the coronavirus disease-2019 (COVID-19) pandemic. Background: The COVID-19 pandemic has disrupted the care of many non-COVID-19 illnesses. Reductions in diagnostic cardiovascular testing around the world have led to concerns over the implications of reduced testing for cardiovascular disease (CVD) morbidity and mortality. Methods: Data were submitted to the INCAPS-COVID (International Atomic Energy Agency Non-Invasive Cardiology Protocols Study of COVID-19), a multinational registry comprising 909 institutions in 108 countries (including 155 facilities in 40 U.S. states), assessing the impact of the COVID-19 pandemic on volumes of diagnostic cardiovascular procedures. Data were obtained for April 2020 and compared with volumes of baseline procedures from March 2019. We compared laboratory characteristics, practices, and procedure volumes between U.S. and non-U.S. facilities and between U.S. geographic regions and identified factors associated with volume reduction in the United States. Results: Reductions in the volumes of procedures in the United States were similar to those in non-U.S. facilities (68% vs. 63%, respectively; p = 0.237), although U.S. facilities reported greater reductions in invasive coronary angiography (69% vs. 53%, respectively; p < 0.001). Significantly more U.S. facilities reported increased use of telehealth and patient screening measures than non-U.S. facilities, such as temperature checks, symptom screenings, and COVID-19 testing. Reductions in volumes of procedures differed between U.S. regions, with larger declines observed in the Northeast (76%) and Midwest (74%) than in the South (62%) and West (44%). Prevalence of COVID-19, staff redeployments, outpatient centers, and urban centers were associated with greater reductions in volume in U.S. facilities in a multivariable analysis. Conclusions: We observed marked reductions in U.S. cardiovascular testing in the early phase of the pandemic and significant variability between U.S. regions. The association between reductions of volumes and COVID-19 prevalence in the United States highlighted the need for proactive efforts to maintain access to cardiovascular testing in areas most affected by outbreaks of COVID-19 infection

Evaluación del tiempo de vida de bacterias potencialmente patógenas en sedimentos marinos

El presente trabajo tuvo por objeto determinar el per&iacute;odo de supervivencia en sedimentos marinos de bacterias con riesgo biol&oacute;gico o indicadoras. Se tomaron muestras de sedimento marino intermareal en dos playas de la ciudad de Comodoro Rivadavia, Argentina; una sometida a contaminaci&oacute;n por efluentes domiciliarios, y otra sin pruebas de contaminaci&oacute;n evidente. Sobre &eacute;stos se realiz&oacute; una caracterizaci&oacute;n inicial por recuento de bacterias en diferentes medios de cultivo (TSA, VRB, VRBG, TCBS, agar bilis esculina y agar cetrimide) y por su identificaci&oacute;n. Tambi&eacute;n se realiz&oacute; un estudio de supervivencia de los microorganismos de inter&eacute;s en microcosmos. Estos fueron monitoreados por conteo de bacterias y por identificaci&oacute;n de los integrantes de inter&eacute;s. Los principales resultados indicaron que existe una marcada diferencia en la composici&oacute;n de la comunidad bacteriana entre ambas muestras. Los g&eacute;neros bacterianos en la muestra contaminada fueron Aeromonas, Salmonella, Pseudomonas, Escherichia, Ochrobactum y Klebsiella, y en la playa no contaminada Bacillus, Paenibacillus, Micrococcus, Photobacterium y Vibrio. El ensayo en microcosmos demostr&oacute; que, luego de 65 d&iacute;as, la comunidad bacteriana de la playa contaminada fue similar a la del sedimento sin contaminaci&oacute;n, indicando que al retirar la fuente de contaminaci&oacute;n, es probable la recuperaci&oacute;n de la zona afectada.Evaluation of life-span of potentially pathogenic bacteria in marine sediments Abstract: The present study had the purpose of determining the survival period of bacteria which represent a biological risk and are indicators of contamination. Inter-tide marine sediment samples were taken at two beaches of the Comodoro Rivadavia city in Argentine; one the beaches was submitted to contamination due to household effluents, and the other without proof of evident contamination. These samples were initially characterized by bacterial counts in different culture media (TSA, VRB, TCBS, bile esculin agar and cetrimide agar) and by their identification. A study of the survival of the target bacteria in microcosm was also done, monitored by bacterial counts and identification of these bacteria. The main results indicated that there was a marked difference in the composition of the bacterial community between the two samples. In the contaminated sample the bacterial genus were Aeromonas, Salmonella, Pseudomonas, Escherichia, Ochrobactum and Klebsiella, and in the non-contaminated beach Bacillus, Paenibacillus, Micrococcus, Photobacterium and Vibrio. The microcosm assay showed that after 65 days the bacterial community of the contaminated beach was similar to that of the non-contaminated beach sediment, indicating that by withdrawing the contamination source, the affected zone can probably be recovered

DETERMINACIÓN DEL CRECIMIENTO DE HONGOS NEMATÓFAGOS EN DIVERSAS FUENTES DE CARBONO

Las enmiendas orgánicas han sido utilizadas para estimular la acción antagónica de los hongos nematófagos depredadores (HND) del suelo, sin embargo, su uso ha producido resultados inconsistentes en el control de nematodos parásitos. Las inconsistencias han sido atribuidas parcialmente a la composición de las enmiendas orgánicas, específicamente al contenido de carbono y nitrógeno. Conocer las preferencias de fuentes de carbono podría ser de utilidad para favorecer la fase depredadora de los HND del suelo. El presente trabajo tiene por objetivo determinar el crecimiento de HND nativos de Costa Rica en fuentes de carbono diversas. Para esto, cepas de HND de las especies Candelabrella musiformis y Arthrobotrys oligospora fueron cultivadas en medios artificiales con diversas fuentes de carbono. La velocidad de crecimiento desarrollada por los HND en los medios de cultivo fue determinada y comparada. Las cepas de C. musiformis y de A. oligospora desarrollaron velocidades de crecimiento en las fuentes de carbono en el siguiente orden: celulosa>quitina> pectina>almidón>leche descremada. Únicamente hubo diferencias significativas en la velocidad de crecimiento en el medio con celulosa, en comparación con los otros medios de cultivo. En dicho medio ambas especies fúngicas crecieron más rápidamente, pero las cepas de A. oligospora crecieron más rápidamente en comparación con las cepas de C. musiformis. Ambas especies de HND desarrollaron velocidades de crecimiento bajas en los medios que contenían almidón y leche descremada

Diversidad de bacterias cultivables con capacidad de degradar hidrocarburos de la playa de Caleta Córdova, Argentina

<span style="font-family: Verdana; font-size: x-small;">En el presente trabajo se estudiaron las comunidades bacterianas aisladas de agua de mar y sedimentos intermareales de Caleta Córdova, norte de Comodoro Rivadavia, Argentina. Tres sitios fueron muestreados estacionalmente entre los años 2005 y 2006; el primer sitio fue una playa pública, el segundo sitio cerca de un puerto pesquero y el tercero cerca de una boya de toma de petróleo. Las comunidades bacterianas fueron determinadas en base a las diferencias en la composición de ácidos grasos de membrana, las bacterias fueron identificadas por medio del Sistema Sherlock MIDI, y el potencial de las comunidades para la utilización de hidrocarburos por la mineralización de gasoil, petróleo, kerosene, aceite lubricante y nafta. Las mineralizaciones evidenciaron la capacidad de los microorganismos para la degradación de hidrocarburos en dos de los sitios estudiados. Se aislaron 251 cepas de las que se lograron identificar 124 correspondientes a 24 géneros y 40 especies; la más frecuente fue <em>Pseudoalteromonas</em>. </span