Empirical guidelines for use of irregular wave model to estimate nearshore wave height / by Michael G. Mattie.

Abstract

Irregular wave model Nearshore waves Wave heights 20. ABSTRACT (Xrorrtlaue on nv aide tf naceaoary and Identify by block number) An irregular wave technique based on a method developed by Goda (1975) and the SPM method for predicting nearshore wave height are compared with wave gage measurements from the CERC Field Research Facility. The SPM method is a classical monochromatic approach, while the irregular wave technique attempts to represent the actual distribution of ocean waves. These two techniques have certain limitations and ranges of applicability. Comparisons with field data will better define the limits and proper use for these techniques. The performance of the models is evaluated for a variety of wave conditions and water depths. DD ,'

Involvement of pertussis toxin‐sensitive GTP‐binding proteins in sphingosine 1‐phosphate‐induced activation of phospholipase CCa2+ system in HL60 leukemia cells

“…Our results clearly indicate that the enzyme activation by the lipid is responsible for Ca 2÷ mobilization, as evidenced from the parallelism of the inhibition of both responses by several agents including PTX (a G-protein inhibitor), U73122 (a phospholipase C inhibitor) and PMA (an inhibitor for the receptormediated phospholipase C activation). In the previous study with Swiss 3T3 fibroblasts [5], the authors concluded that SIPinduced phospholipase C activation is not involved in Ca 2+ mobilization, although exogenous S1P induced both the enzyme activation and Ca 2+ mobilization. This conclusion was based on the observation that PMA treatment abolished SIPinduced activation of the enzyme but never affected the lipidinduced Ca -,+ mobilization [5].…”

“…with an increase in IP3 production probably reflecting the activation of phospholipase C, Ca 2÷ mobilization has been reported to be independent of the IP3 accumulation [5]. On the contrary, a very recent study with the same Swiss 3T3 fibroblasts showed that PTX treatment of the cells inhibited both SIP-induced phospholipase C activation and Ca 2÷ mobilization, suggesting an involvement of PTX-sensitive GTP-binding proteins in the SIP signaling [7].…”

“…Sphingolipids and lysosphingolipids have recently been shown to be involved in the regulation of a variety of cellular processes [1][2][3]. SIP, a phosphorylated product of sphingosine by sphingosine kinase, has been reported to act directly on the internal Ca 2+ pool resulting in Ca 2+ mobilization in a way similar to inositol 1,4,5-trisphosphate in permeabilized cells or purified endoplasmic reticulum [4,5]. SIP is accumulated in response to platelet-derived growth factor and serum in Swiss 3T3 fibroblasts; hence this lipid has been proposed as a second messenger of platelet-derived growth factor and serum on cell proliferation in Swiss 3T3 fibroblasts [6].…”

“…SIP is accumulated in response to platelet-derived growth factor and serum in Swiss 3T3 fibroblasts; hence this lipid has been proposed as a second messenger of platelet-derived growth factor and serum on cell proliferation in Swiss 3T3 fibroblasts [6]. When intact fibroblasts were exposed to exogenous SIP, the lipid also induced Ca 2÷ mobilization [5]. Although the Ca 2+ response is associated *Corresponding author.…”

Anti-ageing effects of a new synthetic sphingolipid (K6EAA-L12) on aged murine skin

“…One particularly interesting sphingolipid metabolite, sphingosine-1-phosphate (S1P), a highly bioactive lipid, has been implicated in both extracellular and intracellular signalling processes (10). S1P acts as a second messenger participating in cellular signalling cascades that lead to cytoskeletal and motility changes, intracellular calcium signalling and protection from apoptosis (11)(12)(13)(14). We have previously developed an S1P-activating compound, K6PC-5, which showed an anti-ageing effect on both intrinsically and extrinsically aged skin (15).…”