Protein topology of presenilin 1

Mutations in a gene encoding a multitransmembrane protein, termed presenilin 1 (PS1), are causative in the majority of early-onset cases of AD. To determine the topology of PS1, we utilized two strategies: first, we tested whether putative transmembranes are sufficient to export a protease-sensitive substrate across a lipid bilayer; and second, we examined the binding of antibodies to specific PS1 epitopes in cultured cells selectively permeabilized with the pore-forming toxin, streptolysin-O. We document that the "loop," N-terminal, and C-terminal domains of PS1 are oriented toward the cytoplasm.     

Efficacy of psychotherapy. Asking the right questions

Economic pressures and "value" judgments both compel and contaminate the current debate on the efficacy of psychotherapy. Too often, complex clinical trial outcome studies ignore the clinical or treatment process, as well as personality or contextual variables. Thus, they fail to build the foundations of a clinical science that makes possible the development of individually tailored treatment approaches and outcome predictions for specific patients with unique personalities, symptoms, and life circumstances. The real challenge, therefore, is for each psychotherapeutic approach to delineate its "process steps" and relate these steps to different outcomes. The "process" is the "final common pathway" for a number of patient, therapist, technique, and contextual variables. The capacity to predict the relationship between process and outcome at each stage in a therapeutic procedure is the relevant clinical test of "efficacy."     

Stability of the polyribosomes of Blakeslea trispora Thaxter during normal translation, its stimulation and inhibition

beta-Ionone is found to stimulate considerably carotinoids synthesis in Blakeslea trispora. The stabilization of carotene-synthesizing ability of B. trispora in the presence of beta-ionine under prolonged incubation time is observed. Stabilization of polyribosomes in the presence of beta-ionine is observed when studying polyribosome content in B. trispora. A hypothesis is expressed on the existence of biochemical "receptors" as a linkage between synthesized protein and destroying mRNA.     

Energetic ion loss detector on the Alcator C-Mod tokamak

A scintillator-based energetic ion loss detector has been successfully commissioned on the Alcator C-Mod tokamak. This probe is located just below the outer midplane, where it captures ions of energies up to 2 MeV resulting from ion cyclotron resonance heating. After passing through a collimating aperture, ions impact different regions of the scintillator according to their gyroradius (energy) and pitch angle. The probe geometry and installation location are determined based on modeling of expected lost ions. The resulting probe is compact and resembles a standard plasma facing tile. Four separate fiber optic cables view different regions of the scintillator to provide phase space resolution. Evolving loss levels are measured during ion cyclotron resonance heating, including variation dependent upon individual antennae.     

Bandwidth limits of luminescent solar concentrators as detectors in free-space optical communication systems

Luminescent solar concentrators(LSCs)have recently emerged as a promising receiver technology in free-space optical communications due to their inherent ability to collect light from a wide field-of-view and concentrate it into small areas,thus leading to high optical gains.Several high-speed communication systems integrating LSCs in their detector blocks have already been demonstrated,with the majority of efforts so far being devoted to maximising the received optical power and the system's field-of-view.However,LSCs may pose a severe bottleneck on the bandwidth of such communication channels due to the comparably slow timescale of the fluorescence events involved,a situation further aggravated by the inherent reabsorption in these systems,and yet,an in-depth study into such dynamic effects remains absent in the field.To fill this gap,we have developed a comprehensive analytical solution that delineates the fundamental bandwidth limits of LSCs as optical detectors in arbitrary free-space optical links,and establishes their equivalence with simple RC low-pass electrical circuits.Furthermore,we demonstrate a time-domain Monte Carlo simulation platform,an indispensable tool in the multiparameter optimisation of LSC-based receiver systems.Our work offers vital insight into LSC system dynamic behaviour and paves the way to evaluate the technology for a wide range of applications,including visible light communications,high-speed video recording,and real-time biological imaging,to name a few.     

Carbon‐Nanotube–PDMS Composite Coatings on Optical Fibers for All‐Optical Ultrasound Imaging

Polymer–carbon nanotube composite coatings have properties that are desirable for a wide range of applications. However, fabrication of these coatings onto submillimeter structures with the efficient use of nanotubes has been challenging. Polydimethylsiloxane (PDMS)–carbon nanotube composite coatings are of particular interest for optical ultrasound transmission, which shows promise for biomedical imaging and therapeutic applications. In this study, methods for fabricating composite coatings comprising PDMS and multiwalled carbon nanotubes (MWCNTs) with submicrometer thickness are developed and used to coat the distal ends of optical fibers. These methods include creating a MWCNT organogel using two solvents, dip coating of this organogel, and subsequent overcoating with PDMS. These coated fibers are used as all‐optical ultrasound transmitters that achieve high ultrasound pressures (up to 21.5 MPa peak‐to‐peak) and broad frequency bandwidths (up to 39.8 MHz). Their clinical potential is demonstrated with all‐optical pulse‐echo ultrasound imaging of an aorta. The fabrication methods in this paper allow for the creation of thin, uniform carbon nanotube composites on miniature or temperature‐sensitive surfaces, to enable a wide range of advanced sensing capabilities.     

Adelaide: Reflections on the scope for public policy

Abstract

Metropolitan Adelaide, a crucible of urban policy innovation in the 1970s, has recently been the subject of pessimistic prognoses about its economic future. The pessimism is overstated. This article documents positive features — economic, institutional, historical — which might form the basis for greater optimism.     

Interdependencies In Urban Research

The papers by Clive Forster and Andrew Beer achieve their intended purpose in identifying and, for the purposes of debate, contrasting two competing visions of the bases and ideals of university research. On the one hand, ‘basic’ research is portrayed as the province of the autonomous and self-motivated scholar, driven by curiosity and answerable only to disciplinary norms and peer evaluation, whose efforts expand knowledge for its own sake. On the other hand, there is the contracted researcher, who might happen to be employed in a university but whose research, based as it is upon whatever funding opportunities happen to present themselves, is oriented toward immediate applied relevance.