Homology [4] is a central concept of comparative and evolutionary biology, referring to the presence of the same bodily parts (e.g., morphological structures) in different species. The existence of homologies is explained by common ancestry, and according to modern definitions of homology, two structures in different species are homologous if they are derived from the same structure in the comm...

ers are a positive step in the direction of reforming the educational system. There are also those who argue that voucher financing is merely a way of shoring up a failing school system, which needs to be abolished in toto and replaced with a flexible system of educational alternatives. Others oppose vouchers because they do not do the whole job of redefining and reallocating educational resour...

Louis Sass has turned schizophrenia on its head. Madness and Modernism: Insanity in the Light of Modern Art, Literature, and Thought brings together more than a hundred years of cumulative writings, observations and theories about schizophrenia, lays bare the traditional framework of assumptions which underpins this considerable body of knowledge, then proposes in its place an alternative way o...

"It has been said that Mineral Trioxide Aggregate is driving an endodontic revolution. Discuss this statement considering the biological and clinical attributes of this innovative material."

ALDO CAROTENUTO, A secret symmetry; Sabina Spielrein between Jung and Freud, trans. from the Italian by Arno Pomerans, John Shepley, and Krishna Winston, New York, Pantheon Books, 1982, 8vo, pp. xix, 250, [no price stated]. HANS KONRAD ISELIN, Zur Entstehung von C. G. Jungs "Psychologischen Typen". Der Briefwechsel zwischen C. G. Jung und Hans Schmid-Guisan im Lichte ihrer Freundschaft, Aarau, ...

During the Cultural Revolution, many leaders of Chinese Communist Party were purged down by the movement: the president, the members of National People’s Congress, the Standing Committee of Politburo in the NPC, the premier, even the district administrative officials. For example, Liu Shaoqi was purged down by the Red Guards, Deng Xiaoping was purged down by ‘Gang of Four’. These officials were...

Yet there are also basic differences between these cell types, in addition to the defining existence of a nucleus in eukaryotes. These stem mainly from genome size. Prokaryotes have significantly smaller genomes than eukaryotes; usually consisting of 1000 to 6000 genes with minimal amounts of regulatory sequences in between. Conversely, human (eukaryotic) cells consist of around 24,000 genes an...