Introduction. Dedekind has determined all groups whose subgroups are all normal (see, e.g., [5, Theorem 12.5.4]). Partially generalizing this, Wielandt showed that a finite group is nilpotent, if and only if all its subgroups are subnormal, and also if and only if all maximal subgroups are normal [5, Corollary 10.3.1, 10.3.4]. Huppert [7, Sätze 23, 24] has shown that if all 2nd-maximal subgroup...

We have reached our goal of implementing a computationally cheap algorithm for realtime rendering of realistic two-dimensional fire. The fire is simulated using computational fluid dynamics, vorticity confinement, and combustion modelling and visualized using black-body radiation. Small rotationally homogenous fires like torches and candles viewed in front are the best candidates when using thi...

Figures we are told can prove anything. Cannot we deduce from those quoted by Professor Lennon in his stimulating contribution to the January Journal that Bristol has been relatively successful in reducing maternal deaths to the occasional unavoidable ones from haemorrhage or toxaemia? I think also that there will be very mixed views concerning the Professor's ideas on domiciliary midwifery. If...

The article proposes a reading of the changes that occurred with regard to use time, during experience confinement, and focuses in particular on impact working from home. results research conducted period pandemic furnish backdrop this analysis. hypothesis is practice home, looked at perspective time patterns, has normalizing effect terms plurality multiformity patterns govern daily life. every...

The current pandemic has changed the social life and learning of most children adolescents around world due to public health restrictions. In response this, they have spent more time on computer television monitor screens, which should negatively impact their eye health. Thus, here we discuss possible association between imposed home confinement risk developing ‘quarantine myopia’ in adolescents.

Not only is space use a result of spatial configuration, but it also greatly determined by social patterns and society’s living modes. The COVID-19 pandemic confinement resulted, worldwide, in 24/7 the domestic setting, which had to be adapted emergence new needs functions space. paper aims at understanding how COVID altered Lisbon current society has maintained some those changes, reflection p...

We study the BV-α-Deconvolution model. It is a family of regularizations of the Barotropic Vorticity (BV) model that generalize the BV-α model and improve its accuracy. A both unconditionally stable and optimally convergent scheme for the BV-α-Deconvolution model is proposed and we show that it is O(α), where N is the deconvolution order, whereas the BV-α model is at most second order accurate....