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Half-lifes (T1/2) of exotic neutron-rich isotopes of Ba, La, Ce, Pr, and Nd were measured at the RIKEN Nishina Center. The experimental setup consisted of the BigRIPS in-flight separator for ion selection identification, the Advance Implantation Detector Array (AIDA) for ions and β detection, and the BRIKEN detector for neutron counting. Using this setup, 4 new T1/2 have been measured for the first time, and 38 T1/2 have been remeasured with improved precision in several cases. These new experimental data should help to constrain theoretical models for calculations of T1/2. The status of the experimental analysis and preliminary results are provided in this contribution.

At the RIKEN Nishina Center, exotic neutron-rich isotopes of Ba, La, Ce, Pr, and Nd were measured. This work reports their half-lives (T1/2) and β-delayed neutron-emission probabilities (Pxn). The setup consisted of the BigRIPS in-flight separator for particle identification, the Advanced Implantation Detector Array (AIDA) for ions and β detection, and the BRIKEN neutron counter for neutron detection. Using this arrangement, 4 new T1/2 and 14 new P1n were measured. Furthermore, 38 T1/2 and 2 P1n values were remeasured, decreasing the uncertainties for some of them. In addition to improving predictions of nucleosynthesis models that describe the production of the rare-earth peak at A ∼ 160 via the r-process, these additional experimental data should help to constrain theoretical models for calculations of T1/2 and Pxn in this region.

Abstract Intraventricular craniopharyngiomas are rare tumours. They are wholly within the third ventricle and can be distinguished from suprasellar lesions which extend into the third ventricle by the presence of an intact floor of the third ventricle. They are attached to the wall of the third ventricle to a variable extent, most commonly in the region of the tuber cinereum. The long-term follow-up on six cases treated by one of the authors is presented. Headache and visual disturbance were the most common presenting features but, unlike the more common suprasellar lesions, symptomatic endocrine disturbances were not a common presenting feature. Total surgical removal can cause hypothalamic damage and the resulting morbidity can be serious and sometimes life-threatening. Subtotal removal followed by radiotherapy is probably the treatment of choice for these lesions. [ABSTRACT FROM AUTHOR]

One-hundred-and-fifty-two patients who underwent surgery for intracranial aneurysm were studied to determine the incidence of postoperative epilepsy in relation to the site of the aneurysm and the type of surgical approach. The overall incidence of epilepsy was 22%. Of the 116 patients treated by the intracranial approach 27.5% developed epilepsy, in contrast with only 5% of the 36 patients who had carotid artery ligation in the neck. Epilepsy occurred most frequently (35%) with middle cerebral artery aneurysms, especially if moderate or severe operative trauma was sustained and there was postoperative dysphasia. [ABSTRACT FROM AUTHOR]

Sixty-nine patients who had neurosurgical treatment for acoustic neuroma by one of two different techniques were studied with a view to determining the incidence of postoperative epilepsy. Fourty-five patients who had larger tumours underwent a combined translabyrinthine and transtentorial neurosurgical approach. For the others with smaller neuromas a translabyrinthine method was used. Only the combined approach was associated with postoperative epilepsy, and it occurred in 22% of the patients. Epilepsy was associated with temporal love trauma during surgery. [ABSTRACT FROM AUTHOR]