Nucleosome structural studies

Chromatin plays a fundamental role in eukaryotic genomic regulation, and the increasing awareness of the importance of epigenetic processes in human health and disease emphasizes the need for understanding the structure and function of the nucleosome. Recent advances in chromatin structural studies, including the first structures of nucleosomes containing the Widom 601 sequence and the structure of a chromatin protein-nucleosome assembly, have provided new insight into stretching of nucleosomal DNA, nucleosome positioning, binding of metal ions, drugs and therapeutic candidates to nucleosomes, and nucleosome recognition by nuclear proteins. These discoveries ensure promising future prospects for unravelling structural attributes of chromatin.     

Developmental studies inDrosophila

Summary Alkaline phosphatases and several dehydrogenases and oxidases separated by a microdisc electrophoresis technique have been studied during larval and early pupal development ofD. pseudoobscura salivary glands, fat body, hemolymph, body wall and whole body. Tissue-specific enzymes were observed and the qualitative differences occurring during the development are discussed.This work was supported in part by grants GM-16736-03 and FR-05426-09 from U.S. Department of Health, Education, and Welfare. The work presented is a portion of a dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy.     

Ancient DNA studies

Now that the hype surrounding Jurassic Park has settled down and we have become relatively used to dramatic headlines announcing the recovery of DNA from exotic fossilized remains, scientists working on ancient DNA are beginning to reflect on the long-term prospects and implications of the subject.¹ The science of ancient DNA has grown exponentially since its birth only ten years ago, and despite serious technical difficulties, it promises to become a revolutionary research tool in anthropology and molecular evolution. The use of bone DNA typing in particular has already yielded useful insights into Polynesian prehistory as well as spectacular applications in the forensic identification of skeletal remains.     

Biofeedback efficacy studies

Biofeedback, a field still in its infancy, has developed treatments that have been used with clinical success in the treatment of a number of disorders. Many have expressed their public concern that biofeedback has not lived up to its early promise and that it has not developed treatments that are, in fact, efficacious. A number of factors, which are inherent in biofeedback research, confound the results of clinical efficacy studies of biofeedback treatments. Researchers interested in the efficacy of biofeedback must address several issues: (1) Rejecting the null hypothesis is not equal to proving the null hypothesis (without the use of power analysis); (2) control for nonspecific effects is not equal to a double-blind experimental design; (3) ignorance of a mechanism of action is not equal to a lack of clinical efficacy; (4) the administration of training is not equal to the subject's learning to criterion; (5) untrained therapists are not equal to trained therapists; (6) statistical significance is not equal to clinical significance; and (7) the laboratory setting is not equal to the clinical setting.     

My primate studies

In this paper, I describe my 62 years in primatology focusing on some of the key findings from fieldwork conducted in Japan, India, and Africa. My first study on nonhuman primates described in detail the division of a troop of Japanese macaques at Takasakiyama. After that, I had an opportunity to work on Hanuman langurs at Dharwar, India. These langurs lived in one-male, multi-female groups. This type of group structure was maintained through takeovers by all-male parties. The adult male and all juvenile males were chased out of the group. By this process, the one-male, multi-female group system was maintained. The incoming adult male bit and killed all infants in the group. Mothers who lost their infants went into estrus and mated with the newly arrived male. For many years, scientists ignored these events or ruled them out as abnormal behavior. My work on Japanese macaques suggested that concentrated resources created by artificial feeding exaggerated dominance rank hierarchies among individuals, whereas it is comparatively relaxed in the natural environment. I also investigated the population dynamics of a troop and the life histories of individuals. From these studies, I documented the frequency of twin births, the carrying of dead infants by mothers, and the occurrence of physical malformations. These observations were made possible through artificial feeding, revealing the merits and demerits of this approach. I pointed out that authors and journal editors must be careful to acknowledge important elements of the environment where studies are conducted, and these should be described when reporting results in scientific articles. My studies of chimpanzees were conducted at Bossou, Guinea. I suggested that there are males who lived outside of bisexual groups. Chimpanzees in this population made and used many kinds of tools. Some of them were observed only at Bossou, and a few were only discovered 20 years after the establishment of Bossou as a research site. After decades of research on tool use in this species, I also suggested that there are cultural zones throughout the geographic distribution of chimpanzees.

     

Cytogenetic studies inEu-Sorghums

Journal of Genetics -