Three protein components of the postsynaptic density – Shank, Homer and SPAR – have been found to regulate the structural and molecular organization of dendritic spines. These new studies reveal ...linkages between receptor complexes, the actin cytoskeleton and signaling molecules that help shape spines.
New insights into the molecular control of spine shape and composition: the postsynaptic proteins Shank, Homer and SPAR help to organize spines
Offshore sedimentary basins of Malaysian region indicate abundant sources of energy at its seabed. Furthermore, depletion of oil and gas reserves in its onshore land and shallow water depth has ...accelerated the exploration toward these deeper waters. Frequent increasing demand requires precise investigation to acquire these energies in optimum custom. A competent exploration structure is also desired for energy extraction from the deep water. In this study, oil and gas status in Malaysian scenario is reconnoitered. As the sea wave influences greatly on offshore structures, approaches for collecting wave data are sightseen. The structural configuration and characteristics of compliant floating spar platform for energy extraction are addressed. The study reveals that the continental shelf offshore of Malaysian waters is divided into seven sedimentary basins, among which three basins have major ongoing oil and gas extraction activity. Around 68% oil and 86% natural gas of the country's reserves are located in East Malaysia at offshore Sabah and Sarawak. Except the Kebabangan field, all the other offshore energy reserves are located at more than 1000 m depth. In lieu of a fixed platform, a floating platform will be a competent energy extraction structure in this deeper water. The deep water wave data can be appropriately obtained in satellite altimetry approach for its extent of accuracy. The first installed spar at Kikeh field denotes bright possibilities of incorporating spar platform in Malaysian sedimentary basins. If spar platforms are installed at these deeper vicinities, all the basins will certainly climb in optimum operation yielding a huge usable energy.
This paper presents the model test results of 3 new spar platforms which were developed based on the OC3-Hywind spar to support a 5-MW wind turbine. By changing the shape but keeping both volume and ...mass of OC3-Hywind spar platform, those platforms were expected to experience different hydrodynamic and hydrostatic loads. The scale models were built with a 1/128 scale ratio. The model tests were carried out in waves, including both rotating rotor effect and mean wind speed. The characteristic motions of the 3 new models were measured; Response Amplitude Operators (RAO) and significant motions were calculated and compared with those of OC3-Hywind.
We recently identified the activity-inducible protein kinase Plk2 as a novel overseer of the balance between Ras and Rap small GTPases. Plk2 achieves a profound level of regulatory control by ...interacting with and phosphorylating at least four Ras and Rap guanine nucleotide exchange factors (GEFs) and GTPase activating proteins (GAPs). Combined, these actions result in synergistic suppression of Ras and hyperstimulation of Rap signaling. Perturbation of Plk2 function abolished homeostatic adaptation of synapses to enhanced activity and impaired behavioral adaptation in various learning tasks, indicating that this regulation was critical for maintaining appropriate Ras/Rap levels. These studies provide insights into the highly cooperative nature of Ras and Rap regulation in neurons. However, different GEF and GAP substrates of Plk2 also controlled specific aspects of dendritic spine morphology, illustrating the ability of individual GAPs/GEFs to assemble microdomains of Ras and Rap signaling that respond to different stimuli and couple to distinct output pathways.
This paper discusses the numerical modeling of the dynamic coupled analysis of the floating platform and mooring/risers using the asynchronous coupling algorithm with the purpose to improve the ...computational efficiency when multiple lines are connected to the platform. The numerical model of the platform motion simulation in wave is presented. Additionally, how the asynchronous coupling algorithm is implemented during the dynamic coupling analysis is introduced. Through a comparison of the numerical results of our developed model with commercial software for a SPAR platform, the developed numerical model is checked and validated.
Spar platforms have several advantages for deploying wind turbines in offshore for depth beyond 120 m. The merit of spar platform is large range of topside payloads, favourable motions compared to ...other floating structures and minimum hull/deck interface. This paper addresses the effect of mooring line damages in responses of spar platform subjected to regular waves. A 1:100 scale model of the spar with taut (intact), taut (damaged) and slack (intact) mooring line configuration was studied in the wave basin (30 × 30 × 3 m) in Ocean Engineering Department of IIT Madras. The heave and surge accelerations along with mooring line tension was measured and used. The surge and heave RAO comparison for all three mooring line conditions shows that the effect of damaged mooring line in surge response is negligible whereas in heave response, taut (damaged) will behave similar to slack (intact) condition. The normalized mooring line tension comparison between taut intact and taut damaged configuration is also presented.
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