Numerical Investigation of the Layer-Inversion Phenomenon in Binary Solid Liquid Fluidized Beds

Layer inversion behaviour in binary-solid liquid fluidized beds is examined using a Combined Continuum and Discrete Model. A suitable bidisperse system was selected from information in the literature. By simulating the fluidization of the system at a range of liquid velocities, varying degrees of segregation and mixing have been observed

Disruptive technology for vector control: the Innovative Vector Control Consortium and the US Military join forces to explore transformative insecticide application technology for mosquito control programmes

Malaria vector control technology has remained largely static for decades and there is a pressing need for innovative control tools and methodology to radically improve the quality and efficiency of current vector control practices. This report summarizes a workshop jointly organized by the Innovative Vector Control Consortium (IVCC) and the Armed Forces Pest Management Board (AFPMB) focused on public health pesticide application technology. Three main topics were discussed: the limitations with current tools and techniques used for indoor residual spraying (IRS), technology innovation to improve efficacy of IRS programmes, and truly disruptive application technology beyond IRS. The group identified several opportunities to improve application technology to include: insuring all IRS programmes are using constant flow valves and erosion resistant tips; introducing compression sprayer improvements that help minimize pesticide waste and human error; and moving beyond IRS by embracing the potential for new larval source management techniques and next generation technology such as unmanned “smart” spray systems. The meeting served to lay the foundation for broader collaboration between the IVCC and AFPMB and partners in industry, the World Health Organization, the Bill and Melinda Gates Foundation and others

Activation of the Bile Acid Pathway and No Observed Antimicrobial Peptide Sequences in the Skin of a Poison Frog

The skin secretions of many frogs have genetically-encoded, endogenous antimicrobial peptides (AMPs). Other species, especially aposematic poison frogs, secrete exogenously derived alkaloids that serve as potent defense molecules. The origins of these defense systems are not clear, but a novel bileacid derived metabolite, tauromantellic acid, was recently discovered and shown to be endogenous in poison frogs (Mantella, Dendrobates, and Epipedobates). These observations raise questions about the evolutionary history of AMP genetic elements, the mechanism and function of tauromatellic acid production, and links between these systems. To understand the diversity and expression of AMPs among frogs, we assembled skin transcriptomes of 13 species across the anuran phylogeny. Our analyses revealed a diversity of AMPs and AMP expression levels across the phylogenetic history of frogs, but no observations of AMPs in Mantella. We examined genes expressed in the bile-acid metabolic pathway and found that CYP7A1 (Cytochrome P450), BAAT (bile acid-CoA: amino acid N-acyltransferase), and AMACR (alphamethylacyl- CoA racemase) were highly expressed in the skin of M. betsileo and either lowly expressed or absent in other frog species. In particular, CYP7A1 catalyzes the first reaction in the cholesterol catabolic pathway and is the rate-limiting step in regulation of bile acid synthesis, suggesting unique activation of the bile acid pathway in Mantella skin. The activation of the bile acid pathway in the skin of Mantella and the lack of observed AMPs fuel new questions about the evolution of defense compounds and the ectopic expression of the bile-acid pathway

Laser-scanning velocimetry: A confocal microscopy method for quantitative measurement of cardiovascular performance in zebrafish embryos and larvae

Abstract Background The zebrafish Danio rerio is an important model system for drug discovery and to study cardiovascular development. Using a laser-scanning confocal microscope, we have developed a non-invasive method of measuring cardiac performance in zebrafish embryos and larvae that obtains cardiovascular parameters similar to those obtained using Doppler echocardiography in mammals. A laser scan line placed parallel to the path of blood in the dorsal aorta measures blood cell velocity, from which cardiac output and indices of vascular resistance and contractility are calculated. Results This technique, called laser-scanning velocimetry, was used to quantify the effects of pharmacological, developmental, and genetic modifiers of cardiac function. Laser-scanning velocimetry was applied to analyze the cardiovascular effects of morpholino knockdown of osmosensing scaffold for MEKK3 (OSM), which when mutated causes the human vascular disease cerebral cavernous malformations. OSM-deficient embryos had a constricted aortic arch and markedly increased peak cell velocity, a characteristic indicator of aortic stenosis. Conclusion These data validate laser-scanning velocimetry as a quantitative tool to measure cardiovascular performance for pharmacological and genetic analysis in zebrafish, which requires no specialized equipment other than a laser-scanning confocal microscope

Germline-dependent gene expression in distant non-gonadal somatic tissues of Drosophila

<p>Abstract</p> <p>Background</p> <p><it>Drosophila </it>females commit tremendous resources to egg production and males produce some of the longest sperm in the animal kingdom. We know little about the coordinated regulation of gene expression patterns in distant somatic tissues that support the developmental cost of gamete production.</p> <p>Results</p> <p>We determined the non-gonadal gene expression patterns of <it>Drosophila </it>females and males with or without a germline. Our results show that germline-dependent expression in the non-gonadal soma is extensive. Interestingly, gene expression patterns and hormone titers are consistent with a hormone axis between the gonads and non-gonadal soma.</p> <p>Conclusions</p> <p>The germline has a long-range influence on gene expression in the <it>Drosophila </it>sexes. We suggest that this is the result of a germline/soma hormonal axis.</p

The Concept of Tectonic Provenance: Case Study of the Gigantic Markagunt Gravity Slide Basal Layer

Formation and evolution of the basal layer in large landslides has important implications for processes that reduce frictional resistance to sliding. In this report, we show that zircon geochronology and tectonic provenance can be used to investigate the basal layer of the gigantic-scale Markagunt gravity slide of Utah, USA. Basal layer and clastic injectite samples have unique tectonic chronofacies that identify the rock units that were broken down during emplacement. Our results show that basal material from sites on the former land surface is statistically indistinguishable and formed primarily by the breakdown of upper plate lithologies during sliding. Decapitated injectites have a different tectonic chronofacies than the local basal layer, with more abundant lower plate-derived zircons. This suggests clastic dikes formed earlier in the translation history from a structurally deeper portion of the slide surface and a compositionally different basal layer before being translated to their current position

Structural Relationships Across the Sevier Gravity Slide of Southwest Utah and Implications for Catastrophic Translation and Emplacement Processes of Long Runout Landslides

The physical processes that facilitate long-distance translation of large-volume gravity slides remain poorly understood. To better understand these processes and the controls on runout distance, we conducted an outcrop and microstructural characterization of the Sevier gravity slide across the former land surface and summarize findings of four key sites. The Sevier gravity slide is the oldest of three mega-scale (\u3e1,000 km2) collapse events of the Marysvale volcanic field (Utah, USA). Field observations of intense deformation, clastic dikes, pseudotachylyte, and consistency of kinematic indicators support the interpretation of rapid emplacement during a single event. Furthermore, clastic dikes and characteristics of the slip zone suggest emplacement involved mobilization and pressurized injection of basal material. Across the runout distance, we observe evidence for progressive slip delocalization along the slide base. This manifests as centimeter- to decimeter-thick cataclastic basal zones and abundant clastic dikes in the north and tens of meters thick basal zones characterized by widespread deformation of both slide blocks and underlying rock near the southern distal end of the gravity slide. Superimposed on this transition are variations in basal zone characteristics and slide geometry arising from interactions between slide blocks during dynamic wear and deposition processes and pre-existing topography of the former land surface. These observations are synthesized into a conceptual model in which the presence of highly pressurized fluids reduced the frictional resistance to sliding during the emplacement of the Sevier gravity slide, and basal zone evolution controlled the effectiveness of dynamic weakening mechanisms across the former land surface

The psychological-type profile of clergywomen in ordained local ministry in the Church of England : pioneers or custodians?

This study employs psychological-type theory to compare the psychological profile of 144 clergywomen serving in ordained local ministry in the Church of England alongside the established profile of 237 professional mobile clergywomen serving in the Church of England published by Francis, Craig, Whinney, Tilley, and Slater. The data found no significant differences between these two groups of clergywomen in terms of orientations (introversion and extraversion) or in terms of the judging process (thinking and feeling). In terms of the perceiving process, there was a significantly higher proportion of sensing types among those serving in ordained local ministry (70% compared with 35%). In terms of the attitudes, there was a significantly higher proportion of judging types among those serving in ordained local ministry (83% compared with 65%). The combined sensing judging (SJ) temperament accounted for 65% of the clergywomen serving in ordained local ministry, compared with 29% of the clergywomen serving in professional mobile ministry in the earlier study. It is argued that the SJ temperament characterises a custodian style of ministry