A mixture of coal wash and fly ash as a pavement substructure material

The reuse of waste materials in engineering projects has become the subject of many research efforts worldwide as it provides economical as well as environmental benefits. Coal wash (CW) and fly ash (FA) are example waste materials that can be used as alternative aggregates in transportation infrastructure projects, specifically as base and subbase materials in roads. Class C FA has been extensively used as a stabilizing material due to its hardening potential. However, Class F fly ash, a non-pozzolanic material when used alone, has not been considered in past research projects. In this study, Class F fly ash is mixed with coal wash as a void filler to enhance its compaction efficiency and produce a compact and well interlocked structure. A laboratory testing plan is performed to assess the geotechnical properties of the mixtures with 0%, 7%, 10% and 13% FA content and it includes compaction tests, unconfined compressive strength tests, California Bearing Ratio (CBR) tests, collapse potential tests and permeability tests. The mixture with 7% FA is selected as the optimum mixture and its potential for tensile cracking under service loads is further investigated using four-point bending tests. Also, the resilient modulus and permanent deformations of the mixture are evaluated under different dry-back conditions using multistage repeated load triaxial tests

Mesoderm is required for coordinated cell movements within zebrafish neural plate in vivo.

BACKGROUND: Morphogenesis of the zebrafish neural tube requires the coordinated movement of many cells in both time and space. A good example of this is the movement of the cells in the zebrafish neural plate as they converge towards the dorsal midline before internalizing to form a neural keel. How these cells are regulated to ensure that they move together as a coherent tissue is unknown. Previous work in other systems has suggested that the underlying mesoderm may play a role in this process but this has not been shown directly in vivo. RESULTS: Here we analyze the roles of subjacent mesoderm in the coordination of neural cell movements during convergence of the zebrafish neural plate and neural keel formation. Live imaging demonstrates that the normal highly coordinated movements of neural plate cells are lost in the absence of underlying mesoderm and the movements of internalization and neural tube formation are severely disrupted. Despite this, neuroepithelial polarity develops in the abnormal neural primordium but the resulting tissue architecture is very disorganized. CONCLUSIONS: We show that the movements of cells in the zebrafish neural plate are highly coordinated during the convergence and internalization movements of neurulation. Our results demonstrate that the underlying mesoderm is required for these coordinated cell movements in the zebrafish neural plate in vivo

Using Neural Networks for Switch Failure Correction in Frequency Reconfigurable Antenna Arrays

Abstract-This paper presents a new technique to correct switch failures in a frequency reconfigurable antenna array. The correction procedure requires at the beginning a detection of the failed switch. The detection process relies on integrating sensing lines within the array substrate to monitor the switch failure. The proposed correction technique is based on using Neural Network (NN) to overcome the failed switch. This is achieved by making the trained NN searches for other switch combinations that give the same array behavior

Behaviour of a Mixture of Coal Wash and Rubber Crumbs under Cyclic Loading

The interest in the utilization of granular waste materials as construction fills in lieu of quarried natural aggregates has been increasing recently, resulting in more sustainable and cost-effective industry practices being adopted. This study proposes a mixture of coal wash (CW; a by-product of coal mining) and rubber crumbs (RC; shredding of waste rubber tires) as a potential capping composite for railways. A series of cyclic triaxial tests mimicking typical rail traffic loads were conducted on CWRC mixtures with and without rest periods to gain an insightful understanding of the deformation mechanism of rubber particles. It is found that the inclusion of RC increases the axial permanent strain, the volumetric strain, and the damping ratio, and it reduces the resilient modulus, the shear modulus, and the breakage index (BI). Also, it is found that the mixture with RC recovers part of its energy dissipation efficiency after a rest period is applied, reducing the breakage index further even when the number of load cycles increases. Accordingly, a modified equation is proposed to determine the void ratio, capturing the deformation of the rubber

The Integration of Reconfigurable Filters for the Matching of Wideband Antennas

Abstract-This paper presents a technique to reduce the cost and overcome the high processing power needed to analyze the signals received by wideband antennas. The idea is based on matching a wideband antenna to a reconfigurable filter. This will allow an easier processing for the received signal and the replacement of the bank of filters needed after the antenna by one reconfigurable filter element. Two prototypes are shown to prove the validity of the proposed technique

Frequency-Tunable and Pattern Diversity Antennas for Cognitive Radio Applications

Frequency-tunable microstrip antennas, for cognitive radio applications, are proposed herein. The approach is based on tuning the operating frequency of a bandpass filter that is incorporated into a wideband antenna. The integration of an open loop resonator- (OLR-) based adjustable bandpass filter into a wideband antenna to transform it into a tunable filter-antenna is presented. The same technique is employed to design a cognitive radio pattern diversity tunable filter-antenna. A good agreement between the simulated and measured results for the fabricated prototypes is obtained. The radiation characteristics of each designed tunable filter-antenna are included herein

Intramedullary melanotic schwannoma

We present a case of an intramedullary melanotic schwannoma (IMS) of the thoracic spinal cord. To our knowledge, this is the seventh reported case of an IMS of the central nervous system. Schwannomas are benign nerve sheath tumors of neural crest origin composed entirely of well differentiated Schwann cells that typically occur in peripheral nerves. Both the intramedullary location and the melanotic component of the reported lesion make it exceedingly rare. We will present our case, theories as to the origin of these tumors, clues in radiographic identification, and current clinical follow-up recommendations

The role of clathrin in post-golgi trafficking in toxoplasma gondii

Apicomplexan parasites are single eukaryotic cells with a highly polarised secretory system that contains unique secretory organelles (micronemes and rhoptries) that are required for host cell invasion. In contrast, the role of the endosomal system is poorly understood in these parasites. With many typical endocytic factors missing, we speculated that endocytosis depends exclusively on a clathrin-mediated mechanism. Intriguingly, in Toxoplasma gondii we were only able to observe the endogenous clathrin heavy chain 1 (CHC1) at the Golgi, but not at the parasite surface. For the functional characterisation of Toxoplasma gondii CHC1 we generated parasite mutants conditionally expressing the dominant negative clathrin Hub fragment and demonstrate that CHC1 is essential for vesicle formation at the trans-Golgi network. Consequently, the functional ablation of CHC1 results in Golgi aberrations, a block in the biogenesis of the unique secretory microneme and rhoptry organelles, and of the pellicle. However, we found no morphological evidence for clathrin mediating endocytosis in these parasites and speculate that they remodelled their vesicular trafficking system to adapt to an intracellular lifestyle

Effects of oral intake of water in patients with oropharyngeal dysphagia

<p>Abstract</p> <p>Background</p> <p>Dysphagia is associated with numerous medical conditions and the major intervention to avoid aspiration in people with dysphagia involves modifying the diet to thickened fluids. This is associated with issues related to patient quality of life and in many cases non-compliance leading to dehydration. Given these concerns and in the absence of conclusive scientific evidence, we designed a study, to further investigate the effects of oral intake of water in people with dysphagia.</p> <p>Methods</p> <p>We monitored lung related complications, hydration levels and assessed quality of life in two groups of people with dysphagia. The control group was allowed only thickened fluids and patients in the intervention group were allowed access to water for a period of five days.</p> <p>Results</p> <p>Our findings indicate a significantly increased risk in the development lung complications in patients given access to water (6/42; 14.3%) compared to the control group (0/34; no cases). We have further defined patients at highest risk, namely those with degenerative neurologic dysfunction who are immobile or have low mobility. Our results indicate increased total fluid intake in the patients allowed access to water, and the quality of life surveys, albeit from a limited number of patients (24% of patients), suggest the dissatisfaction of patients to diets composed of only thickened fluids.</p> <p>Conclusions</p> <p>On the basis of these findings we recommend that acute patients, patients with severe neurological dysfunction and immobility should be strongly encouraged to adhere to a thickened fluid or modified solid consistency diet. We recommend that subacute patients with relatively good mobility should have choice after being well-informed of the relative risk.</p> <p>Trial registration</p> <p>Australia and New Zealand Clinical Trials Register (ANZCTR): <a href="http://www.anzctr.org.au/ACTRN12608000107325.aspx">ACTRN12608000107325</a></p

A Polarised Population of Dynamic Microtubules Mediates Homeostatic Length Control in Animal Cells

An analysis of cells grown on micro-patterned lines, and of cells during zebrafish development, identifies a population of microtubules that align along the long axis of cells to mediate homeostatic length control