The deeper portions of the vertebrate tree are becoming reasonably well understood [ 12- 19] and many of the remaining problems are nearer the tips of the tree, at the family, genus and species levels.
Although there are still many remaining unsolved problems, new discoveries based on RNA-seq analysis ranging from genomic imprinting (Gregg et al., 2010) to differential expression (Anders and Huber, 2010; Trapnell et al., 2012) promise an exciting future.
Many of CSN's remaining problems stem from Brazil's inefficient infrastructure, on which CSN depends to power its plants and supply and transport its raw materials and finished products.
Since the first register in 1999, 868 sites, or 60% of the total, have been repaired or conservation is under way, but the problems of many remaining on the list for years are intractable.
Survivors and perpetrators alike suffer from mental health problems, yet many remain within the confines of toxic masculinity – unable to express emotion in fear of appearing weak, with some instead resorting to violence against newly empowered women in their lives.
Many problems remain, including widespread financial difficulties, and there is a perception that many national associations, which have supported Blatter, have been over-reliant on funds from Fifa.
Many problems remain, notably red tape.
Solzhenitsyn acknowledged that "many problems remained", including the widening gap between Russia's rich and poor.
Many problems remain, however, in the correlation of the continental and the marine deposits.
