Light conditions and heterogeneity in illumination affect growth and survival of Octopus vulgaris paralarvae reared in the hatchery

In order to succeed in common octopus (Octopus vulgaris) aquaculture, it is necessary to overcome the massive paralarval mortalities, which are likely related to zootechnical and/or nutritional aspects. Among the zootechnical aspects, the effect of light could be vital for the development of paralarvae given their sophisticated visual system. O. vulgaris paralarvae display vertical behavior in the wild, being in deeper waters during the day and close to the surface at night. For this reason, the present study traces a collection of light assays in captivity, to test ecologically-driven hypotheses on the growth and survival of octopus paralarvae. The first assay tested a factorial combination of light colors (blue vs white) and intensity (low ~13 lx (36 W/m2), medium ~87 lx (151 W/m2) and high ~265 lx (422 W/m2)). The results pointed to a significant negative impact of low light intensities (13 and 87 lx) on paralarval growth. The second assay was designed to contrast light colors (blue vs white), different levels of intensities (300 lx (478 W/m2) vs 600 lx (1077 W/m2)) and partial coverage of the tanks using a shade mesh, named as “shadow zone” (half-covered vs non-covered tanks). In half-covered tanks, survival was significantly improved, with the best results coming from half-covered tanks with blue light and 600 lx, but no differences in dry weight were observed. The third experiment tested a factor called “light source position” with two levels: “Control” when the light incidence angle was 0° with respect to the normal direction (i.e. perpendicular to the water surface), and “Oblique” when the light incidence angle was 60° with respect to the normal direction. In this experiment, survival significantly improved under oblique light but no differences in dry weight were detected. The last experiment was an unifactorial design combining “light source position” and “tank partial coverage” with three treatments: i) control light with uncovered tanks, ii) oblique light with uncovered tanks, iii) control light with semi-covered tanks. Oblique light with uncovered tanks was associated with a higher survival rate but without statistical significance, probably due to data variability. It can be concluded that light intensity tended to affect paralarval dry weight, whereas the existence of a shadow zone or oblique light are more related with an improvement of survival rate

Photometric follow-up of the 20 Myr old multi-planet host star V1298 Tau with CHEOPS and ground-based telescopes

Context. The 20 Myr old star V1298 Tau hosts at least four planets. Since its discovery, this system has been a target of intensive photometric and spectroscopic monitoring. To date, the characterisation of its architecture and planets' fundamental properties has been very challenging. Aims: The determination of the orbital ephemeris of the outermost planet V1298 Tau e remains an open question. Only two transits have been detected so far by Kepler/K2 and TESS, allowing for a grid of reference periods to be tested with new observations, without excluding the possibility of transit timing variations. Observing a third transit would allow for better constraints to be set on the orbital period and would also help in determining an accurate radius for V1298 Tau e because the previous transits showed different depths. Methods: We observed V1298 Tau with the CHaracterising ExOPlanet Satellite (CHEOPS) to search for a third transit of planet e within observing windows selected to test three of the shortest predicted orbital periods. We also collected ground-based observations to verify the result found with CHEOPS. We reanalysed Kepler/K2 and TESS light curves to test how the results derived from these data are affected by alternative photometric extraction and detrending methods. Results: We report the CHEOPS detection of a transit-like signal that could be attributed to V1298 Tau e. If so, that result would imply that the orbital period calculated from fitting a linear ephemeris to the three available transits is close to ~45 days. Results from the ground-based follow-up marginally support this possibility. We found that i) the transit observed by CHEOPS has a longer duration compared to that of the transits observed by Kepler/K2 and TESS; and ii) the transit observed by TESS is >30% deeper than that of Kepler/K2 and CHEOPS, and it is also deeper than the measurement previously reported in the literature, according to our reanalysis. Conclusions: If the new transit detected by CHEOPS is found to be due to V1298 Tau e, this would imply that the planet experiences TTVs of a few hours, as deduced from three transits, as well as orbital precession, which would explain the longer duration of the transit compared to the Kepler/K2 and TESS signals. Another and a priori less likely possibility is that the newly detected transit belongs to a fifth planet with a longer orbital period than that of V1298 Tau e. Planning further photometric follow-up to search for additional transits is indeed necessary to solve the conundrum, as well as to pin down the radius of V1298 Tau e

Synthesis, Structure, and Catalytic Studies of Palladium and Platinum Bis-Sulfoxide Complexes

The bis-sulfoxide ligand p-tolyl-binaso and its derivatives can be used to synthesize neutral and cationic palladium and platinum complexes. Various Pt bis-sulfoxide complexes could be made by using the precursor Pt{(M,SS,SS)-p-tolyl-binaso}Cl2 (5a) and abstracting the chlorides with silver salts. The Pd analogue of this compound (4) could not be used in the same way. In this case, the sulfoxides appear to be very weakly coordinated and different methods to make stable Pd bis-sulfoxide complexes had to be found. The nature of the bonding in the synthesized compounds was studied through analysis of their IR and NMR spectra and X-ray crystal structures. These studies revealed that the trans effect of other ligands in the complex is quite significant in determining the lability of the metal–sulfoxide bond. Some of the more stable platinum structures were then tested for their activity as catalysts in hydroboration and diboration reactions

Desenvolvimentismo e neodesenvolvimentismo: tragédia e farsa Developmentalism and new developmentalism: tragedy and farce

A pretensão do neodesenvolvimentismo de pleitear a continuidade do desenvolvimentismo não encontra nenhum fundamento objetivo. As duas expressões do pensamento econômico correspondem a épocas históricas distintas e representam espectros ideológicos opostos. Ao identificar a realidade da economia brasileira contemporânea com o desenvolvimento capitalista virtuoso, o novo desenvolvimentista revela&#8209;se tal qual é - uma apologia do poder. Não passa de um esforço provinciano para dar roupa nova à velha teoria da modernização como solução para os graves problemas das populações que vivem no elo fraco do sistema capitalista mundial.<br>The pretension of the new developmentalism to plead the continuity of the old developmentalism has no objective foundation. The two expressions of economic thought correspond to different historical epochs and represent opposing sides of the ideological spectrum. When the new developmentalism identifies the contemporary reality of the Brazilian economy with virtuous capitalist development, it reveals what it is really: an apologia for power. It is nothing more than a parochial effort to make up the old theory of modernization as a solution to the serious problems of the population living in the weak link of the capitalist world system