J André - Böcker

, Jean ANDRE Universite de Paris XI, ORSAY, France. Sperm cells have long been considered as the most highly specialized of all living cells. They surely are, being very diverse, very complex, containing organelles which do not exist in any other cell -such as acrosome or crystallized mitochondria- and being endowed with a very unique behaviour, that is to meet and recognize the ovum, pierce its protective envelopes and inject into its cytoplasm a most precious deposit, the haploid genome of the species. It is Baccio Baccetti's merit to have felt the need for a confrontation of the scientists working on sperm in order to clarify the apparent complexity of the enormous amount of knowledge accumulated on the subject. Thus, he successfully inaugurated the series of the InternationaZ Symposia on SpermatoZogy. The Seillac edition is the fourth in the series. After an initial stage during which morphology was predominant, our meetings have turned more and more towards function. It has been the will of the French Organizing Committee to devote this meeting mainly to Eutherians, and, among those, to man, in connection with the conflicting necessities to help the sterile couples and to contrul the population explosion at the surface of the world.

The NATO Advanced Study Institute on "Quantum Chemistry of Polymers; Solid State Aspects" lIIas held at the MARITIM Congress Hotel Braunlage/Harz in the Federal Republic of Germany from July 25 - August 5, 1983. We lIIish to express our deep gratitude to the NATO Scientific Affairs Division, the main sponsor of the Institute, and to the National Foundation for Cancer Research, Bethesda, Maryland for their substantial support. We sincerely thank Dr. Craig Sinclair, Director of the NATO Advanced Study Institutes program as lIIell as the IIIhole Advanced Study Institute/Advanced Research Workshop Advisory Board of the NATO Scientific Affairs Division, IIIho have honored us by holding their external annual meeting during this School in Braunlage. We are very much indebted also to Dr. Mario Di Lullo, Director of the Advanced Research Workshop program of the NATO Scientific Affairs Division IIIho together lIIith Dr. Sinclair has given a very informative lecture about the NATO ASI/ARW programs. Special thanks are due to Mr. Franklin Salisbury, Executive Director of the National Foundation for Cancer Research, to Mrs. Tamara Salisbury, Deputy Director of the National Foundation for Cancer Research and to Dr. Mary Hennen Aldridge, President of the National Foundation for Cancer Research, IIIho also honored the School lIIith their presence.

The NATO Advanced Study Institute on "Quantum Chemistry of Polymers; Solid State Aspects" lIIas held at the MARITIM Congress Hotel Braunlage/Harz in the Federal Republic of Germany from July 25 - August 5, 1983. We lIIish to express our deep gratitude to the NATO Scientific Affairs Division, the main sponsor of the Institute, and to the National Foundation for Cancer Research, Bethesda, Maryland for their substantial support. We sincerely thank Dr. Craig Sinclair, Director of the NATO Advanced Study Institutes program as lIIell as the IIIhole Advanced Study Institute/Advanced Research Workshop Advisory Board of the NATO Scientific Affairs Division, IIIho have honored us by holding their external annual meeting during this School in Braunlage. We are very much indebted also to Dr. Mario Di Lullo, Director of the Advanced Research Workshop program of the NATO Scientific Affairs Division IIIho together lIIith Dr. Sinclair has given a very informative lecture about the NATO ASI/ARW programs. Special thanks are due to Mr. Franklin Salisbury, Executive Director of the National Foundation for Cancer Research, to Mrs. Tamara Salisbury, Deputy Director of the National Foundation for Cancer Research and to Dr. Mary Hennen Aldridge, President of the National Foundation for Cancer Research, IIIho also honored the School lIIith their presence.