In Virus Veritas Lockdown and Happiness Under COVID-19.

It is widely accepted that individual happiness is not, or not solely, related to material possessions, at least once basic needs are fulfilled. It has been demonstrated that interpersonal relationships and social capital matter too, and people whose values are more centred on material possessions have a greater probability of being less happy. Is this still true during the COVID-19 pandemic, when interpersonal relations, health and economic security are threatened and feelings of insecurity emerge? This is the issue that we address in this paper. We exploited the unique natural situation of the pandemic and lockdown in Italy to investigate the relationship between happiness and relational and material goods. Data collected by questionnaire during the lockdown suggests that the main direct effect of the pandemic on the happiness of respondents was related to the effect of the pandemic and lockdown on interpersonal relationships. Those who declared that COVID and lockdown had jeopardized their interpersonal relationships were significantly less likely to report higher levels of happiness, especially when controlling for other personal and contextual covariates. An important gender, religious and town size effect also emerged. Moreover, relational goods and good health were considered to be the most important determinants of happiness, though people were not so worried about their own health.

Metamorphosis delay in Xenopus laevis (Daudin) tadpoles exposed to a 50 Hz weak magnetic field.

PURPOSE: The experiment was performed to prove that exposure to a relatively weak extremely low frequency (ELF) magnetic field retards tadpoles' development. METHODS: Two cohorts of Xenopus laevis laevis (Daudin) tadpoles were exposed during their immature period ( approximately 60 days) to a 50 Hz magnetic field of 63.9 < or = B < or = 76.4 microT rms (root mean square, average values) magnetic flux density in a solenoid. At the same time, as controls, two comparable cohorts were reared in two aquariums remote from the solenoid. Cohorts' degree of development was quantified by daily inspections of animal limbs and attributing them to a stage of the Nieuwkoop and Faber ( 1956 ) classification. The experiment was replicated three times. RESULTS: (a) Mean developmental rate of exposed cohorts was reduced with respect to controls (0.43 vs. 0.48 stages/day, p < 0.001) starting from early larval stages; (b) Exposure increased the mean metamorphosis period of tadpoles by 2.4 days compared with the controls (p < 0.001); (c) Maturation rates of exposed and control tadpoles changed during maturation period; and (d) Important mortality, malformations or teratogenic effects were not observed in exposed matured tadpoles. CONCLUSION: A long-term exposure of X. laevis tadpoles to a relatively weak 50 Hz magnetic field causes a sub-lethal effect that slows down their larval developmental rate and delays their metamorphosis.

Localization patterns of fibroblast growth factor 1 and its receptors FGFR1 and FGFR2 in postnatal mouse retina.

Fibroblast growth factors (FGFs) exert basic functions both during embryonic development and in the adult. The expression of FGFs and their receptors has been reported in mammalian retinas, although information on the organization of the FGF system is still incomplete. Here, we report a detailed double-label immunohistochemical investigation of the localization patterns of FGF1 and its receptors FGFR1 and FGFR2 in adult and early postnatal mouse retinas. In adult retinas, FGF1 is localized to ganglion cells, horizontal cells, and photoreceptor inner and outer segments. FGFR1 is found in ganglion cells and Müller cells, whereas FGFR2 is primarily located in ganglion cells, the nuclei of Müller cells, and glycine-containing amacrine cells. During postnatal development, the patterns of FGF1, FGFR1, and FGFR2 immunostaining are similar to those in the adult, although transient FGF1-expressing cells have been detected in the proximal inner nuclear layer before eye opening. These patterns are consistent with a major involvement of FGF1, FGFR1, and FGFR2 in ganglion cell maturation (during development) and survival (in the adult). Moreover, FGF1 may affect amacrine cell development, whereas Müller cells appear to be regulated via both FGFR1 and FGFR2 throughout postnatal life. In immature retinas, large numbers of amacrine cells, including those containing calbindin and glycine, display both FGF1 and FGFR2 immunoreactivities in their nuclei, suggesting an action of FGF1 on FGFR2 leading to the maturation of these amacrine cells during a restricted period of postnatal development.

In Vivo and in Vitro Experimental Analysis of Lens Regeneration in Larval Xenopus laevis: (lens/regeneration/transdifferentiation).

After lentectomy of larval Xenopus laevis, the outer cornea undergoes tissue transformation resulting in formation of a new lens. This lens regeneration is triggered and sustained by neural retina. In the present study, lens-forming transformation of the outer cornea was completed in vitro when the outer cornea was cultured within the lentectomized eye-cup. Well-differentiated lens fiber cells, which showed positive immunofluorescence for total crystallins, were also formed when the outer cornea was cultivated with the retina. No lens tissue was formed when the cornea was cultured alone. Lens-forming transformation, originating from the cornea three and five days after lentectomy, completely regressed when the tissue was isolated in vitro. Fom the present and previous findings, we concluded that, the interaction of corneal cells with the retina plays a decisive role in lens regeneration in situ.

Relationships between Presence of the Eye Cup and Maintenance of Lens-Forming Capacity in Larval Xenopus laevis.

The lentectomized eye of larval Xenopus laevis can regenerate a lens by a process of lens-transdifferentiation of the cornea and pericorneal epidermis. These tissues can form the lens only when they become in direct communication with the environment of the vitreous chamber (neural retina) indicating that the eye cup plays a fundamental role in this process. In this work the role of the eye cup in the maintainance of the lens-forming capacity of the cornea and pericorneal epidermis was studied by allowing these tissues to cover the enucleated orbit for different periods, and then implanting them into the vitreous chamber of the contralateral eye. Under these experimental conditions the maintainance of the lens-forming capacity of the cornea and pericorneal epidermis showed no significant correlation with the time from enucleation to implantation.