Exploring mitochondrial cholesterol (mChol) signalling for therapeutic intervention in neurological conditions

The pharmacological targeting of cholesterol levels continues to draw interest due to the vast success of therapeutics such as statins in extending life expectancy by modifying the prognosis of diseases associated with the impairment of the lipid metabolism. Advances in our understanding of mitochondrial dysfunction in chronic age‐related diseases of the brain have unveiled an emerging role for mitochondrial cholesterol (mChol) in their pathophysiology, thus delineating an opportunity to provide mechanistic insights and explore strategies of intervention. This review draws attention to novel signalling mechanisms in conditions linked with impaired metabolism associated with impaired handling of cholesterol and its oxided forms (oxysterols) by mitochondria. By emphasising the role of mChol in neurological diseases we here call for novel approaches as well as new means of assessment

MitoCPR: Meticulous Monitoring of Mitochondrial Proteostasis

Mitochondrial protein import stress compromises functioning of the organelles, due to inadequate supply of inner mitochondrial proteins. Weidberg and Amon (2018) describe a new monitoring pathway in budding yeast, which restores mitochondrial function following the clearing of accumulated unfolded pre-transported mitochondrial proteins, by devising a molecular strategy of overexpressing bi-partite-containing mitochondrial proteins

An Alternative Method of Measuring SPT Energy

Despite problems associated with its repeatability and reliability, the standard Penetration Test (SPT) continues to be the most widely used in-situ test for liquefaction potential assessment. There are many factors known to influence the SPT results but the most significant factor affecting the N value is the amount of hammer energy delivered into the drill rods. The existing method of SPT energy measurement consists of attaching a load cell near the top of the drill rods and measuring the force time history during hammer impact. An alternative method of SPT energy determ1nat1on based on measurement of both force and acceleration time history is described. It is shown that the proposed method is more fundamental and avoids several shortcomings in the existing method. Field measurements are presented and SPT energies calculated by both methods are compared

General Report Session 3: Deformation and Liquefaction of Sands, Silt, Gravels and Clays

It has been almost 27 years since the damaging earthquakes of 1964 which occurred in Niigata, Japan and in Alaska, USA, focused the geotechnical engineers\u27 attention to liquefaction as a major problem in earthquake engineering. Considerable research and studies have been conducted on the subject of earthquake induced liquefaction since that time and these have included field observations, laboratory experiments and model tests, and theoretical studies. Progress in understanding the liquefaction phenomenon, in the assessment of liquefaction potential, and in the solutions to mitigate the liquefaction hazard has been made, yet the problem remains controversial in many respects, as reflected by the many stimulating papers presented in this session. The word liquefaction has been associated with many phenomena observed in the field during and after earthquakes such as sand boils, flow slides, lateral spreads, loss of bearing capacity and porewater pressure rise. In laboratory tests, liquefaction has been defined in several ways relating to pore pressure buildup under undrained cyclic straining or loading, or the development of a specified amount of shear strain in a fixed number of cycles of loading. Laboratory studies have also shown that the liquefaction phenomenon can be divided into three different behaviors, namely, true liquefaction, limited liquefaction and cyclic mobility. In theoretical studies, liquefaction occurs when the seismic-induced cyclic shear stress exceeds the cyclic shear resistance, or when the seismic porewater pressure increases to equal the effective stress. To compare the results from different papers, one must bear in mind the different definitions used by the various authors. Liquefaction-caused failure is really the result of excessive permanent deformation, e.g. tilting, settlement or heave of structures, excessive slumping or distortion, and sliding of slopes. Liquefaction-induced ground deformation is receiving more attention in the last decade. Soil failure due to liquefaction was the most dominant cause of damage in the recent M 7. 7 Luzon earthquake of July 16, 1990 in the Philippines. Remedial measures or ground improvement techniques to reduce the liquefaction hazards are becoming more common in recent years, not only for seismic rehabilitation of existing sites but also for newly developed sites. Refinements in equipment and techniques of existing methods are being developed. As well, new methods of ground improvements are being introduced. The M 7.1 Lorna Prieta earthquake of October 17, 1989 showed convincingly that liquefaction hazard can be avoided or effectively mitigated by soil densification prior to earthquake

Comparison of Monomethylhydrazine/Hydroxypropylcellulose and Hydrocarbon/Silica Gels

Experimental studies have been performed to investigate rheology and droplet burning with different types of gelled propellants. Monomethylhydrazine has been gelled with organic hydroxypropylcellulose. JP-8 and RP-1 hydrocarbon gels have been produced with inorganic fumed silica particles. Rheological characterization showed the differences in terms of viscosity and yield stress behavior due to different types of gelling agents. Herschel-Bulkley and Carreau-Yasuda models have been used to characterize the gels with inorganic and organic gelling agents, respectively. First experiments with the Monomethylhydrazine/hydroxypropylcellulose gels showed a typical swelling process during combustion with a flexible viscous droplet surface. Contrary to that, the hydrocarbon/silica gels burned while a rigid silica structure was built, which remained unburned. Burning drop measurements have been compared to the d^2-squared law

Future-Viewer: An Efficient Framework for Navigating and Classifying Audio-Visual Documents

In this paper we present an intuitive framework named Future-Viewer, introduced for the effective visualization of spatiotemporal low-level features, in the context of browsing and retrieval of a multimedia document. This tool is used to facilitate the access to the content and to improve the understanding of the semantics associated to the considered multimedia document. The main visualization paradigm employed consists in representing a 2D feature space in which the video document shots are located. The features that characterize the 2D space's axes can be selected by the user. Shots with similar content fall near each other, and the tool offers various functionalities for automatically nding and annotating shot clusters in the feature space. These annotations can also be stored in MPEG7 format. The use of this application to browse the content of few audio-video sequences demonstrate very interesting capabilities

Downhole Seismic Cone Analysis Using Digital Signal Processing

In-situ measurement of the dynamic characteristics of surficial soils is becoming more common in geotechnical practice for prediction of ground surface motions from earthquake excitation and to evaluate foundations for vibrating equipment. Techniques for these measurements have been under development at the University Of British Columbia (U.B.C.) since 1980. The paper discusses many practical considerations with respect to equipment (sources, receivers, trigger, etc.) and procedures that can affect the interpretation and analysis of seismic cone results. A brief review is given of the cross-over method as used at UBC to determine interval shear velocity travel times from downhole seismic cone testing. A more detailed description is provided for the cross-correlation technique used in the frequency domain that has recently been incorporated into the analysis procedure. Comparisons of these two methods are presented and discussed

Liquefaction Characteristics of Undisturbed Soils

Undrained cyclic triaxial tests were performed on undisturbed samples of natural soil deposits in order to investigate some of the factors affecting its liquefaction characteristics. It was shown that when the cyclic deviator stress is normalized with respect to major principal effective stress the number of cycles to liquefaction is not affected by sample size, consolidation stress, anisotropic consolidation, and grain size and density variations. However, liquefaction resistance was markedly increased by increasing over-consolidation ratio and aging. Also, sample disturbance of loose soils results in an increase, or unconservative measurement, of liquefaction resistance

lnsitu Measurement of Damping of Soils

The Seismic Cone Penetration Test (SCPT) has been shown to give reasonable results for insitu measurements of shear wave velocity, and this paper extends this work to include measurements of damping. The relevant equations of motion are described, factors affecting amplitude decay are discussed, and the nature of damping is summarized. Consideration is given to some of the practical aspects of pre-processing of signals. Three methods of damping calculation are presented. The first two, attenuation coefficient and modified SHAKE methods, require the application of amplitude corrections, which is not straight-forward, give variable results, and indicate negative damping in a clayey silt layer. The third, the spectral slope method eliminates the need for amplitude corrections and gives less variable and more acceptable results. The spectral slope method gave damping measurements of about 2% to 3% for sand and 0.3% to 0.5% for silt, at low strain levels of 10-4 to 10-3%

Gamers’ Sensations of Spatial, Social, And Co-Presence While Playing Online Video Games

There is an increasing number of video gamers who are playing games online. Previous research has demonstrated that off line gamers experience sensations of presence “the illusion of non-mediation” (Lombard & Ditton, 1997). The current study, explores through focus groups, the type of presence online gamers report experiencing. The results demonstrate that online gamers report having sensations that can be classified into all three main presence types: spatial (physical), social, and co-presence