Most of the nuclei in the nuclear chart are deformed except for those in the vicinity of the magic numbers. It is difficult to treat such nuclei within the framework of the standard (spherical) shell model. On the other hand, the necessity for a proper quantum mechanical treatment of high-spin states has been steadily growing ever since modern experimental techniques made it possible to measure the fine details of the high-spin states of heavy nuclei. The present article reviews an approach based on the angular momentum projection technique which was initiated in the late seventies for the purpose of carrying out shell model configuration mixing calculations efficiently. A large number of examples is presented with an emphasis on the physical interpretation of the numerical results. Computing time for the whole spectrum up to spin ≈ 40 of an axially symmetric rare-earth nucleus takes only a few minutes on a Mainframe, showing the efficiency of the method. Most of the present calculations were carried out on a Workstation, but computation on a modern PC also presents no problem, so that one can enjoy a genuine quantum mechanical analysis of high-spin data using a facility available everywhere. Detailed technical information which may be useful for programming purposes is given in an Appendix.

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Nuclear receptors comprise a large and expanding family of transcription factors involved in diverse aspects of animal physiology and development, the functions of which can be modulated in a spatial and temporal manner by access to small lipophilic ligands and/or the specificity of their own localized expression. Here we report the identification of a human nuclear receptor that reveals a unique proximal box (CNGCSG) in the DNA-binding domain. The conservation of this feature in its nematode counterpart suggests the requirement for this type of P box in the genetic cascades mediated by nuclear receptors in a wide variety of animal species. The expression of this receptor, PNR (photoreceptor-specific nuclear receptor), appears strongly restricted in the retina, exclusively in photoreceptor cells. In human cell lines, PNR expression was observed in Y79 retinoblastoma along with other photoreceptor marker genes such as CRX. Among vertebrate receptors, PNR shares structural kinship with an orphan receptor TLX, and despite distinct differences in the DNA binding domain, PNR is able to recognize a subset of TLX target sequences in vitro. Analyses of the human PNR gene revealed its chromosomal position as 15q24, a site that has recently been reported as a susceptible region for retinal degeneration. These data support a role for PNR in the regulation of signalling pathways intrinsic to the photoreceptor cell function.