Abstract. This paper examines the ice and dense water production in the Okhotsk Sea coastal polynyas for the 1990-1995 winters. The dominant polynyas occur on the northwest and northern shelves and in Shelikhov Bay. We use an algorithm developed for the special sensor microwave/ imager (SSM/I) to derive for each polynya the area and composition of thin ice and open water and a heat flux algorithm to derive the ice and brine production. Historic oceanographic observations show that the northwest shelf is the only North Pacific region where the (•o = 26.8 potential density surface outcrops to the surface and is also that part of the Okhotsk shelf where the densest water is observed to occur. In support of these observations, we find that the northwest shelf polynya is the dominant ice and brine producer, contributing on average about 55% of the total production. Shelikhov Bay is the second largest producer with about 25% of the total; this region has been previously neglected by both oceanographic and remote sensing studies. Using a combination of two dense water production models, we find that the 6 year average dense water production lies between 0.2-0.4 Sv. The ice and brine production for the dominant northwest shelf vary interannually by a factor of 3, while the production from all the northern polynyas varies by factor of 2. The source of the variability for the northwest shelf comes from the fact that the southwest-to-northeast trend of the coastline and the mean winter geostrophic wind velocities are roughly parallel, which means that small variations in the wind direction yield large changes in the ice production.

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A sterol-polyether conjugate, 5-androstene3j3,17j3-bis[(oxycarbonyl)hexaethylene glycol] (l), has been synthesized via condensation of the bis-chloroformate derivative of 5-androstene-3j3,17j3-diol with hexaethylene glycol mono(triphenylmethy1 ether), followed by deprotection. This conjugate, which is composed of a long and rigid hydrophobic unit, two flexible hydrophilic chains that are linked to the hydrophobic unit, and a pendant polar head group, was designed as a prototype for new classes of compounds that are intended to serve as functional equivalents of the polyene macrolide antibiotic amphotericin B. Analysis of the surface pressurearea isotherm of 1, generated at the air-water interface, indicates a limiting area of ca. 60 A2 per molecule. This value is fully consistent with a model in which the sterol nucleus (ca. 40 A2) and one pendant polyether chain (ca. 20 A2) define the collisional area of the surfactant; that is, it supports the existence of a 'folded" conformation at the air-water interface. Incorporation of 1 into egg PC vesicular membranes leads to ion channel formation, as demonstrated by 23Na NMR spectroscopy. Operationally, 1 has been found to have an ionophoric activity that is very similar to that found for a synthetic "bouquet" molecule, but significantly less than amphotericin B, itself.

Surface contouring by phase-shifting digital holography is proposed and verified by experiments and numerical simulations. Digital holograms are recorded before and after mode hopping of a laser diode subject to current tuning, and the difference of the reconstructed phases at each wavelength is computed to deliver surface contours of a diffusely reflecting surface. Since normal incidence on the object is employed, the method does not need the removal of the tilt component and is free from the shadowing effect as advantages over the dual-incidence method proposed before by the first author.

The encapsulation effect of thermal chemical-vapour-deposition polymer films (TCVDPF) has been studied for organic light-emitting diodes (OLED). We used poly-p-xylylene (PPX) and/or poly-2-chloro-p-xylylene (PCPX) films as TCVDPF. For the encapsulation, TCVDPF was deposited on the OLED during a dry process at room temperature. The lifetime of an encapsulated OLED with 0.6 µm thick TCVDPF was about four times longer than that of a non-encapsulated OLED in air. The lifetime of the OLED increased with increasing thickness of the TCVDPF. We conclude that the effect of TCVDPF encapsulation on the long-term stability of the OLED is due to the prevention of oxygen and moisture in air and several other factors.

The marine colonial hydroid Tubularia mesembryanthemum produces a morphologically unique dispersive stage, the actinula larva. Detailed observations were made on the behaviors and nematocyte dynamics of actinula larvae during attachment and morphogenesis by employing microscopic and time lapse video techniques. These observations produced four primary results. (1) Actinula larvae demonstrated two forms of attachment: temporary attachment by atrichous isorhiza (AI)-nematocysts discharged from the aboral tentacle (AT) tips-and permanent settlement by cement secretion from the columnar gland cells of the basal protrusion. (2) During larval settlement, numerous AIs were discharged from the AT tips with sinuous movement and rubbing of the tentacles onto the substrata, leading to "nematocyte-printing" around the settlement site. (3) Simultaneous with the discharge of the AIs, migration of stenoteles, desmonemes, and microbasic mastigophores occurred, resulting in a dramatic change of nematocyte composition in the ATs after larval settlement. This was in parallel with changes in larval behavior and the tentacle function. (4) Nematocyte-printing behavior during settlement could be recognized as metamorphic behavior responsible for irreversible changes in AT function, from attachment to feeding and defense.

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