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We have studied water contained in the perfluorinated sulfonic acid (denoted as RSO3H) membrane by FT-IR spectroscopy. The IR spectra of the membrane, which absorbed water quickly even from the air, changed so drastically during dehydration that they showed clearly two isosbestic points in the 4000−1500 cm^-1 region. Analysis of the IR spectral changes made it clear that water molecules exist mostly as H3O⁺ in equilibrium with RSO3^- and RSO3H in the membrane. The IR change accompanying dehydration was found to result from the reaction as RSO3^- + H3O⁺ → RSO3H + H2O(evaporating out). The IR spectrum of H3O⁺ was clearly separated, which shows a broad OH stretching absorption with two unseparated peaks around 3370 and 3120 cm^-1 and an OH deformation absorption at about 1720 cm^-1. The spectrum is distinctively different from that of water separated, coexisting with H3O⁺, RSO3^-, and RSO3H in the membrane, which shows OH stretching and deformation absorptions at about 3480 and 1628 cm^-1, respectively.

Heparin-binding epidermal growth factor-like growth factor (HB-EGF) transduces mitogenic signals through the EGF receptor (EGFR). There are two forms of HB-EGF, the membrane-anchored form (pro-HB-EGF) and the soluble form (sHB-EGF). We studied the biological activity of pro-HB-EGF by using a model in which pro-HB-EGF-expressing effector cells was co-cultured with EGFR-expressing target cells. The DER cell, an EGFR-expressing derivative of the interleukin-3-dependent hematopoietic 32D cell line, grows well in the presence of EGF or sHB-EGF without IL-3. When DER cells were co-cultured on a monolayer of Vero-H cells overexpressing pro-HB-EGF, growth inhibition and subsequent apoptosis were induced in the DER cells even in the presence of excess amounts of EGF or sHB-EGF. Such growth inhibition of DER cells was abrogated when specific antagonists for pro-HB-EGF were added in the culture medium or when direct contact of DER cells with Vero-H cells was prevented, indicating that pro-HB-EGF is involved in this inhibitory effect. Pro-HB-EGF-induced apoptosis of DER cells was also observed even in the presence of IL-3. This rules out the possibility of simple competition between soluble EGFR ligands and pro-HB-EGF. Moreover, 32D cells expressing EGFR mutant composed of the extracellular and the transmembrane domain of EGFR and the cytoplasmic domain of erythropoietin receptor did not undergo apoptosis by co-culture with Vero-H cells, indicating that the inhibitory signal induced by pro-HB-EGF-expressing Vero-H cells is mediated to DER cells via EGFR and that the cytoplasmic domain of EGFR is essential for pro-HB-EGF-induced apoptosis. From these results, we concluded that pro-HB-EGF has unique biological activity through cell-cell contact that is distinct from the activity of sHB-EGF.

In vitro association of Xenopus nucleoplasmin and mammalian nonhistone chromosomal high mobility group 1 (HMG1) protein with nuclei isolated from rat liver was examined. Efficient association of nuclear proteins with isolated nuclei requires ATP, HCO3-, and Ca2+. Association occurred at 33 degrees C but not at 4 degrees C. ATP could be replaced by adenosine 5'-[alpha,beta-methylene]triphosphate (pp[CH2]pA), a nonhydrolyzable ATP analog. pp[CH2]pA associated with nuclei at 33 degrees C and nucleoplasmin and HMG1 rapidly associated with the pp[CH2]pA-bound nuclei at 4 degrees C. Competition studies showed that these associations at both 33 degrees C and 4 degrees C were specific. More than 80% of the bindings of nuclear proteins to the nuclear surface were blocked by wheat germ agglutinin.

Conventional solid-state ²⁷Al and ³¹P magic-angle spinning nuclear magnetic resonance (MAS NMR) and an advanced two-dimensional ²⁷Al multiple-quantum MAS NMR (2D ²⁷Al MQMAS NMR) have been applied to characterize MoO3−P2O5−Al2O3 hydrotreating catalysts. These catalysts were prepared by a sol−gel method with high Mo loadings (with Mo expected amounts of ~20 and ~30 wt %) and a wide range of P content (from 0 to 13 wt % of P). The chemical environments of Al and P strongly depend on the nature of the P precursor used in the sample preparation (H3PO4 or P2O5) and on the amount of P and Mo. From the ²⁷Al MAS NMR measurements on dried P-containing samples, formation of octahedral aluminum (Alocta) and of AlPO4 (Altetra−O−P surface species) in small amounts was observed. After calcination at 500 °C, the formation of tetrahedral aluminum (Altetra) and pentacoordinated aluminum (Alpenta) was also observed. The presence of molybdenum favored the interaction of phosphorus with the alumina framework, leading to significant amounts of Altetra−O−P. At higher P and Mo loadings, Al2(MoO4)3 was also detected in the calcined sample. ³¹P MAS NMR measurements revealed the formation of monomeric or polymeric P oxocompounds after drying and polymeric P oxocompounds or AlPO4 after calcination, respectively. The use of P2O5 as a P precursor gave rise to the formation of polymerized P oxocompounds rather than of AlPO4 after calcination in the absence of Mo. 2D ²⁷Al MQMAS NMR gave an improved resolution compared with conventional ²⁷Al MAS NMR. In dried samples, pure alumina and MoO3−alumina showed a single distorted Alocta site while P-containing catalysts showed additional octahedral and tetrahedral aluminum sites interacting with phosphorus (Alocta−O−P and Altetra−O−P, respectively). After calcination, mainly Alocta and Altetra sites with a small amount of Alpenta sites were observed in pure alumina. The presence of Mo introduced a large distortion in the alumina framework, since the amount of Alpenta significantly increased in the presence of Mo. Altetra−O−P sites were also detected in P-containing alumina catalysts, but the Alocta−O−P sites disappeared after calcination.

Investigations were conducted with underyearling coho salmon Oncorhynchus kisutch reared in marine net-pens to determine the extent of genetic involvement in traits associated with smoltiffcation and saltwater adaptation and to assess genetic relationships among these traits. Data were obtained from two brood years (1977 and 1978) of experimental families formed by a nested mating design and consisted of length and weight measurements and morphological smolt assessments at 7 and 11 months postfertilization. Reasonably high heritability estimates (h2= 0.22–0.29) were obtained for all smoltification traits except survival (h2= 0.07). Correlation estimates among the variables suggested a strong genetic relationship between size and smoltification traits, with the exception of percent survival. The use of these estimates for genetic improvement was illustrated by two types of selection index. Substantial increases in smoltification and saltwater-adaptation traits appeared to be possible. Received April 25, 1983 Accepted March 20, 1984