The influence of process gas type on the enamel surface condition of a high power diode laser generated single-stage ceramic tile grout seal

Almost all laser materials processing operations require the simultaneous use of an process or assist gas. This paper examines the use of O2, Ar, N2 and He as process gasses during the firing of a vitreous enamel to form a single-stage ceramic tile grout seal with a high power diode laser (HPDL) and the effects thereof on the surface condition of the glaze. The findings revealed marked differences in the surface condition of the HPDL generated enamel glaze depending upon the process gas used. The use of O2 as the process gas was seen to result in glazes with far fewer microcracks and porosities than those generated with any of the other three gasses, particularly He. Such differences were found to be due to the ability of the smaller O2 gas molecules to dissolve molecularly into the open structure of the HPDL generated enamel glaze and also, the inherent reactiveness of O2 which consequently effects exothermic reactions when it is used as a process gas. Both occurrences were seen, in turn, to affect the cooling rate and therefore the tendency of the molten glaze to generate microcracks when cooled

A comparative investigation of the wear characteristics of a high power diode laser generated single-stage tile grout and commercial epoxy tile grout

A comparative study of a single-stage ceramic tile grout, generated using a 60 W high power diode laser (HPDL), and a commercially available tile grout has determined the wear characteristics of the two materials. Within both normal and corrosive environmental conditions, the single-stage ceramic tile grout proved to have a superior wear rate over the epoxy tile grout, 0.9 mg/cm2/h compared with 125 mg/cm2/h when in an HNO3 environment respectively. Likewise, life assessment testing revealed that the single-stage ceramic tile grout gave an increase in wear life of 4 to 42 times over the commercially available epoxy tile grout, depending upon the corrosive environment. It is believed that the economic and material benefits to be gained from the deployment of such an effective and efficient means of sealing ceramic tiles could be significant

Normalised Root Mean Square and Amplitude of Sidebands of Vibration Response as Tools for Gearbox Diagnosis

Quick assessment of the condition of gearboxes used in helicopters is a safety requirement. One of the most widely used helicopter on-board-mounted condition monitoring system these days is the Health and Usage Monitoring System. It has been specifically designed to monitor the condition of all safety-critical components operating in the helicopter through calculation of so-called condition indicators (CIs) - signal processing routines designed to output a single number that represents the condition of the monitored component. Among number of available parameters, there is a couple of CIs that over the years of testing have earned a reputation of being the most reliable measures of the gear tooth condition. At the same time, however, it has been observed that in some cases, those techniques do not properly indicate the deteriorating condition with the propagation of a gear tooth fault with the period of operation. Hence, three more robust methods have been suggested, which are discussed in this article

Editorial: Mental practice: Clinical and experimental research in imagery and action observation

First paragraph: This editorial accompanies 18 articles as part of aFrontiersresearch topic. The aim of this research topic was to clarify the underlying mechanisms involved in mental practice of action, bringing together evidence from a range of disciplines including cognitive neuroscience, experimental neuropsychology, sport and movement science, clinical neuropsychology and clinical neurology. The need to clarify the underlying mechanisms of mental practice is a pressing one. Mental practice of action has been explored in sport psychology for several decades, with the aim to use mental practice to improve sport performance. However, following the discovery of the mirror neuron system (see for example,Rizzolatti and Craighero, 2004), the perspective of mental practice has changed to a rationale based on neuroscience and to research focussed on understanding the neural processes of mental practice. Evidence that the brain simulates action has resulted in a common understanding of “functional equivalence” (Jeannerod, 1994): the idea that thementalrepresentation of an action or percept in the person's mind is the neural “equivalent” to thephysicalaction oractualpercept. This ability to mentally represent action using the motor system allows for action simulation, providing conscious mental rehearsal of movement (imagery), but also allows for a common percept when observing the movements of others. Finally, in recent years, the disciplines of clinical neuropsychology and neurology have begun to use mental rehearsal of action, ormental practice, to produce improvements normally attributed to practicing actual movements

Dual modal imaging agents based on chromophore-bearing DTPA analogues

Two new DTPA analogues, centrally (L1) and terminally (L2) functionalised with a 1,8-naphthalimide chromophore, have been successfully prepared and fully characterized.</p

Latitudinal variation in monthly-scale reproductive synchrony among Acropora coral assemblages in the Indo-Pacific

Early research into coral reproductive biology suggested that spawning synchrony was driven by variations in the amplitude of environmental variables that are correlated with latitude, with synchrony predicted to break down at lower latitudes. More recent research has revealed that synchronous spawning, both within and among species, is a feature of all speciose coral assemblages, including equatorial reefs. Nonetheless, considerable variation in reproductive synchrony exists among locations and the hypothesis that the extent of spawning synchrony is correlated with latitude has not been formally tested on a large scale. Here, we use data from 90 sites throughout the Indo-Pacific and a quantitative index of reproductive synchrony applied at a monthly scale to demonstrate that, despite considerable spatial and temporal variation, there is no correlation between latitude and reproductive synchrony. Considering the critical role that successful reproduction plays in the persistence and recovery of coral reefs, research is urgently needed to understand the drivers underpinning variation in reproductive synchrony

Latitudinal variation in monthly-scale reproductive synchrony among Acropora coral assemblages in the Indo-Pacific

Early research into coral reproductive biology suggested that spawning synchrony was driven by variations in the amplitude of environmental variables that are correlated with latitude, with synchrony predicted to break down at lower latitudes. More recent research has revealed that synchronous spawning, both within and among species, is a feature of all speciose coral assemblages, including equatorial reefs. Nonetheless, considerable variation in reproductive synchrony exists among locations and the hypothesis that the extent of spawning synchrony is correlated with latitude has not been formally tested on a large scale. Here, we use data from 90 sites throughout the Indo-Pacific and a quantitative index of reproductive synchrony applied at a monthly scale to demonstrate that, despite considerable spatial and temporal variation, there is no correlation between latitude and reproductive synchrony. Considering the critical role that successful reproduction plays in the persistence and recovery of coral reefs, research is urgently needed to understand the drivers underpinning variation in reproductive synchrony

The relationship between members of the canonical NF-κB pathway, components of tumour microenvironment and survival in patients with invasive ductal breast cancer

The aim of the present study was to examine the relationship between tumour NF-κB activation, tumour microenvironment including local inflammatory response (LIR) and cancer-specific survival in patients with operable ductal breast cancer. Immunohistochemistry (tissue microarray of 376 patients) and western blotting (MCF7 and MDA-MB-231 breast cancer cells) was performed to assess expression of key members of the canonical NF-κB pathway (inhibitory kappa B kinase (IKKβ) and phosphorylated p65 Ser-536 (p-p65)). Following silencing of IKKβ, cell viability and apoptosis was assessed in both MCF7 and MDA-MB-231 cell lines. P-p65 was associated with cancer-specific survival (CSS) (nuclear P=0.042 and total P=0.025). High total p-p65 was associated with increase grade tumour grade (P=0.010), ER positivity (P=0.023), molecular subtype (P=0.005), lower Klintrup- Makinen grade (P=0.013) and decreased CD138 count (P=0.032). On multivariate analysis, total p-p65 expression independently associated with poorer CSS (P=0.020). In vitro work demonstrated that the canonical NF-κB pathway was inducible by exposure to TNFα in ER-positive MCF7 cells and to a lesser extent in ER-negative MDAMB- 231 cells. Reduction of IKKβ expression by siRNA transfection increased levels of apoptosis and reduced cell viability in both MCF7 (P= 0.001, P=0.002, respectively). This is consistent with the hypothesis that canonical IKKβ-NF-κB signalling drives tumour survival. These results suggest that activation of the canonical NF-κB pathway is an important determinant of poor outcome in patients with invasive ductal breast cancer