Context.
Stellar activity is currently challenging the detection of young planets via the radial velocity (RV) technique.
Aims.
We attempt to definitively discriminate the nature of the RV variations ...for the young active K5 star BD+20 1790, for which visible (VIS) RV measurements show divergent results on the existence of a substellar companion.
Methods.
We compare VIS data with high precision RVs in the near-infrared (NIR) range by using the GIANO–B and IGRINS spectrographs. In addition, we present for the first time simultaneous VIS-NIR observations obtained with GIARPS (GIANO–B and HARPS–N) at Telescopio Nazionale Galileo (TNG). Orbital RVs are achromatic, so the RV amplitude does not change at different wavelengths, while stellar activity induces wavelength-dependent RV variations, which are significantly reduced in the NIR range with respect to the VIS.
Results.
The NIR radial velocity measurements from GIANO–B and IGRINS show an average amplitude of about one quarter with respect to previously published VIS data, as expected when the RV jitter is due to stellar activity. Coeval multi-band photometry surprisingly shows larger amplitudes in the NIR range, explainable with a mixture of cool and hot spots in the same active region.
Conclusions.
In this work, the claimed massive planet around BD+20 1790 is ruled out by our data. We exploited the crucial role of multi-wavelength spectroscopy when observing young active stars: thanks to facilities like GIARPS that provide simultaneous observations, this method can reach its maximum potential.
Soon after the Black Death reached Italy in the autumn of 1347, the city-states of the quadrilateral instituted Boards of Health dedicated to keeping the disease out, containing its spread and ...eradicating conditions in which it thrived. Italian practices were later imitated by countries across Europe but not until the early eighteenth century were preventative measures introduced at state level in England. When epidemic struck Provence in 1720, the Whig ministry took powers to impose embargoes, quarantining of ships and cordons sanitaires around infected towns, but was forced to beat a partial retreat by attacks from mercantile interests, by the Country opposition and by anti-contagionists, attacks fuelled by appeals to preserve ‘English Liberties’.It was in this context that Defoe published Due Preparations for the Plague, As Well for Soul as Body. The treatise proposes measures both ‘General’ (to be carried out by governments and magistates, and publicly financed) and ‘Particular’ (organised by individuals and families). Taken together they constitute a series of experiments in avoiding contagion by ‘separating the People as much as possible from one another’. Experimental also with respect to serious plague discourse is Defoe’s intermingling of narrative and dialogue as means of helping readers imagine themselves already under the plague, and motivate them to prepare for an event never experienced. In A Journal of the Plague Year Defoe was to rework his proposals, re-framing and reinterpreting them in a less prescriptive mode and a more collective slant.
The Oran earthquake of 9th October 1790 in NW Algeria caused heavy damage in that city, and originated a tsunami observed in Almeria and Cartagena, SE Spain. It occurred in a region of low seismicity ...in comparison with other regions east of Algeria. The abundant contemporary documentation analysed in the present study, some of it not used previously, confirms a maximum intensity of IX–X (EMS-98) for Oran city. The estimated focal parameters are: origin time 01 h 15 m or 01 h 30 m UT, duration 1-to-2 min, a macroseismic offshore epicentre at 35.9°N, 0.6°W to explain the generation of the tsunami, and estimated magnitude 6.0–6.5. The rupture is complex, formed by two events, and may have been associated with NE-SW oriented thrust faults present in the area.
Adam Smith was a philosopher before he ever wrote about economics, yet until now there has never been a philosophical commentary on the Wealth of Nations. Samuel Fleischacker suggests that Smith's ...vastly influential treatise on economics can be better understood if placed in the light of his epistemology, philosophy of science, and moral theory. He lays out the relevance of these aspects of Smith's thought to specific themes in the Wealth of Nations, arguing, among other things, that Smith regards social science as an extension of common sense rather than as a discipline to be approached mathematically, that he has moral as well as pragmatic reasons for approving of capitalism, and that he has an unusually strong belief in human equality that leads him to anticipate, if not quite endorse, the modern doctrine of distributive justice.
Context. The young active star BD +20 1790 has been inferred to host a substellar companion from radial-velocity measurements that detected the reflex motion induced on the parent star. Aims. We ...attempt to completely characterize the radial-velocity signal in order to assess its nature. Methods. We used the CORALIE spectrograph to obtain precise (~10 m s-1) radial-velocity measurements of this active star, while characterizing the bisector span variations. We took particular care to correctly sample both the proposed planetary orbital period, of 7.8 days, and the stellar rotation period, of 2.4 days. Results. We measure a smaller radial-velocity signal (with peak-to-peak variations <500 m s-1) than reported previously, and of different amplitude for two different campaigns. A periodicity similar to the rotational period is found in the data, as well as a clear correlation between radial velocities and bisector span. These results imply that the radial-velocity variations of the star are photospheric in origin and not caused by a barycentric movement movement of the star, and contradict the previous detection of a hot-Jupiter.
Durante la última década del siglo XVIII, varios grupos de mapuches, pehuenches y huilliches del sur de Chile y del oeste de Argentina mantenían su independencia territorial a través de una serie ...de alianzas con la corona española a cambio de recibir apoyo militar contra otras parcialidades indígenas rivales. Diversos estudios se han enfocado en el robo de ganado del sur bonaerense por parte de estos indígenas y en su traslado y comercio ilícito en Chile, este artículo plantea que ejercer el poder y defender el espacio comunitario era fundamental para lasprácticas políticas, principalmente, de los mapuches. El análisis de la correspondencia de funcionarios españoles y misioneros franciscanos de aquella época en Concepción y Valdivia (Chile), y en Mendoza (Argentina), sugiere que definir y defender una comunidad a través de acuerdos con militares y misioneros"”dos facetas del Estado español"”jugaban un rol principal en la concepción misma del poder al seno de la comunidad mapuche; en vez de ser una oportunidad económica o una de las acciones para obtener ganancias.
Context. Stellar activity is currently challenging the detection of young planets via the radial velocity (RV) technique. Aims. We attempt to definitively discriminate the nature of the RV variations ...for the young active K5 star BD+20 1790, for which visible (VIS) RV measurements show divergent results on the existence of a substellar companion. Methods. We compare VIS data with high precision RVs in the near-infrared (NIR) range by using the GIANO–B and IGRINS spectrographs. In addition, we present for the first time simultaneous VIS-NIR observations obtained with GIARPS (GIANO–B and HARPS–N) at Telescopio Nazionale Galileo (TNG). Orbital RVs are achromatic, so the RV amplitude does not change at different wavelengths, while stellar activity induces wavelength-dependent RV variations, which are significantly reduced in the NIR range with respect to the VIS. Results. The NIR radial velocity measurements from GIANO–B and IGRINS show an average amplitude of about one quarter with respect to previously published VIS data, as expected when the RV jitter is due to stellar activity. Coeval multi-band photometry surprisingly shows larger amplitudes in the NIR range, explainable with a mixture of cool and hot spots in the same active region. Conclusions. In this work, the claimed massive planet around BD+20 1790 is ruled out by our data. We exploited the crucial role of multi-wavelength spectroscopy when observing young active stars: thanks to facilities like GIARPS that provide simultaneous observations, this method can reach its maximum potential.
The various chemicals in industrial wastewater can be beneficial for improving its circularity. If extraction methods are used to capture valuable components from the wastewater and then recirculate ...them throughout the process, the potential of the wastewater can be fully exploited. In this study, wastewater produced after the polypropylene deodorization process was evaluated. These waters remove the remains of the additives used to create the resin. With this recovery, contamination of the water bodies is avoided, and the polymer production process becomes more circular. The phenolic component was recovered by solid-phase extraction and HPLC, with a recovery rate of over 95%. FTIR and DSC were used to evaluate the purity of the extracted compound. After the phenolic compound was applied to the resin and its thermal stability was analyzed via TGA, the compound's efficacy was finally determined. The results showed that the recovered additive improves the thermal qualities of the material.
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