Rotational viscosity in ferroelectric liquid crystals estimated from transient light scattering and dielectric properties

A new method for the estimation of rotational viscosity of ferroelectric liquid crystals using transient light scattering (TSM) is reported. The relation between rotational viscosity, spontaneous polarization, and dielectric dispersion frequency is studied as a function of the racemization. The rotational viscosity is almost independent of spontaneous polarization and there is no obvious correlation between rotational viscosity and dispersion frequency. The dispersion frequency is confirmed to be inversely proportional to the square of the helical pitch. The rotational viscosity calculated from this relation is consistent with that from the new TSM method.This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in M. Ozaki, T. Hatai, K. Nakao, and K. Yoshino, Journal of Applied Physics 65, 3602 (1989) and may be found at https://doi.org/10.1063/1.342639

INDONESIAN HATCHERY REARED SEABASS LARVAE (Lates calcarifer), ASSOCIATED WITH VIRAL NERVOUS NECROSIS (VNN)

Mass tuortality atuongs seabass larvae, Lates calcarifer, reared in hatcheries in East and Bali due to viral nervous necrosis were investigated. outbreaks of the disease occured from August to Novetnber 1997

Fungi isolated from cultured eggs, alevins and broodfish of brown trout in a hatchery affected by saprolegniosis

P. 510-518The aquatic fungi cultured from eggs, alevins and broodfish of brown trout Salmo trutta belonged to the genus Saprolegnia and were identified as S. diclina, S. australis, S. ferax, S. furcata, S. hypogyna, S. unispora and S. parasitica. The species obtained from infected eggs and alevins were different to those from infected fish. Several Saprolegnia species were isolated from eggs and alevins, whereas all the isolates obtained from broodfish were the pathogenic S. parasitica.S

Modification of Collagen by 3-Deoxyglucosone Alters Wound Healing through Differential Regulation of p38 MAP Kinase

Background: Wound healing is a highly dynamic process that requires signaling from the extracellular matrix to the fibroblasts for migration and proliferation, and closure of the wound. This rate of wound closure is impaired in diabetes, which may be due to the increased levels of the precursor for advanced glycation end products, 3-deoxyglucosone (3DG). Previous studies suggest a differential role for p38 mitogen-activated kinase (MAPK) during wound healing; whereby, p38 MAPK acts as a growth kinase during normal wound healing, but acts as a stress kinase during diabetic wound repair. Therefore, we investigated the signaling cross-talk by which p38 MAPK mediates wound healing in fibroblasts cultured on native collagen and 3DG-collagen. Methodology/Principal Findings: Using human dermal fibroblasts cultured on 3DG-collagen as a model of diabetic wounds, we demonstrated that p38 MAPK can promote either cell growth or cell death, and this was dependent on the activation of AKT and ERK1/2. Wound closure on native collagen was dependent on p38 MAPK phosphorylation of AKT and ERK1/2. Furthermore, proliferation and collagen production in fibroblasts cultured on native collagen was dependent on p38 MAPK regulation of AKT and ERK1/2. In contrast, 3DG-collagen decreased fibroblast migration, proliferation, and collagen expression through ERK1/2 and AKT downregulation via p38 MAPK. Conclusions/Significance: Taken together, the present study shows that p38 MAPK is a key signaling molecule that plays

Branchiostegite melanization and microsporidia-like infection in cultured Macrobrachium rosenbergii in Thailand

In Thailand, farming the giant freshwater prawn, Macrobrachium rosenbergii, is a viable aquaculture industry. In 1995-96, giant freshwater prawns collected from grow out ponds located in Supanburi Province, Thailand showed severe branchiostegite melanization associated with poor growth and high cumulative mortality in affected ponds. The objective this study was to report the histopathological features of branchiostegite melanization and associated lesions in affected giant freshwater prawns. The gross lesions displayed by the collected prawns were bilateral branchiostegite melanization in the medial surfaces with normal underlying gill lamellae. Histopathological examination revealed a massive number of sporonts in the gill tissue causing a hyperinfection. Enlargement of the sporonts occurred in the gills. High magnification using a light microscope revealed massive round microsporidia-like spores in the sporonts measuring 1-2 m in diameter. The muscles of collected prawns were normal showing no signs of opaque cottony or milky white coloration. The hepatopancreas, however, were yellow in color. Positive Giemsa and PAS stained spores were found in hemocytes and cytoplasm of hepatopancreas cells. Because these results do not include electron-micrographic data, more observation is needed before the spores can be identified as microsporidia

A note on the fossil marine fauna dredged from the Japanese Seas

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