An Investigation of the Adsorption Characteristics of 5'ATP and 5'AMP onto the Surface of Caso4 x 2H2O

A model has been proposed in which solid surfaces can act as a site for cataletic activity of condensation reactions for certain biomolecules. From this model, the adsorption characteristics of 5'ATP and 5'AMP onto the surface of CaSO4.2H2O was chosen for study. It has been proven that 5'ATP and 5'AMP do adsorb onto the surface of CaSO4. Studies were then made to determine the dependence of absorption versus time, concentration, ionic strength and pH. It was found that the adsorption of the nucleotides is highly pH dependent, primarily determined by the phosphate acid groups of the nucleic acid molecule. From this investigation, the data obtained is discussed in relation to the model for the prebiotic earth

An investigation of the adsorption characteristics of 5 prime ATP and 5 prime AMP onto the surface of CaSO sub 4 x 2H sub 2 O

A model has been proposed (Lahev and Chans, 1982) in which solid surfaces can act as a site for catalytic activity of condensation reactions for certain biomolecules. From this model, the adsorption characteristics of 5'ATP and 5'AMP onto the surface of CaSO4 2H2O was chosen for study. It has been proven that 5'ATP and 5'AMP do adsorb onto the surface of CaSO4. Studies were then made to determine the dependence of adsorption versus time, concentration, ionic strength and pH. It was found that the adsorption of the nucleotides is highly pH dependent, primarily determined by the phosphate acid groups of the nucleic acid molecule. From this investigation, the data obtained are discussed in relation to the model for the prebiotic earth

Optimisation of distributed feedback laser biosensors

A new integrated optical sensor chip is proposed, based on a modified distributed- feedback (DFB) semiconductor laser. The semiconductor layers of different refractive indices that comprise a laser form the basis of a waveguide sensor, where changes in the refractive index of material at the surface are sensed via changes in the evanescent field of the lasing mode. In DFB lasers, laser oscillation occurs at the Bragg wavelength. Since this is sensitive to the effective refractive index of the optical mode, the emission wavelength is sensitive to the index of a sample on the waveguide surface. Hence, lasers are modelled as planar waveguides and the effective index of the fundamental transverse electric mode is calculated as a function of index and thickness of a thin surface layer using the beam propagation method. We find that an optimised structure has a thin upper cladding layer of ~0.15 mum, which according to this model gives detection limits on test layer index and thickness resolution of 0.1 and 1.57 nm, respectively, a figure which may be further improved using two lasers in an interferometer-type configuration

Implementable Wireless Access for B3G Networks - III: Complexity Reducing Transceiver Structures

This article presents a comprehensive overview of some of the research conducted within Mobile VCE’s Core Wireless Access Research Programme,1 a key focus of which has naturally been on MIMO transceivers. The series of articles offers a coherent view of how the work was structured and comprises a compilation of material that has been presented in detail elsewhere (see references within the article). In this article MIMO channel measurements, analysis, and modeling, which were presented previously in the first article in this series of four, are utilized to develop compact and distributed antenna arrays. Parallel activities led to research into low-complexity MIMO single-user spacetime coding techniques, as well as SISO and MIMO multi-user CDMA-based transceivers for B3G systems. As well as feeding into the industry’s in-house research program, significant extensions of this work are now in hand, within Mobile VCE’s own core activity, aiming toward securing major improvements in delivery efficiency in future wireless systems through crosslayer operation

Dual-frequency GPS survey for validation of a regional DTM and for the generation of local DTM data for sea-level rise modelling in an estuarine salt marsh

Global average temperatures have risen by an average of 0.07°C per decade over the last 100 years, with a warming trend of 0.13°C per decade over the last 50 years. Temperatures are predicted to rise by 2°C - 4.4°C by 2100 leading to global average sealevel rise (SLR) of 2 – 6mm per year (20 – 60cms in total) up to 2100 (IPCC 2007) with impacts for protected coastal habitats in Ireland. Estuaries are predominantly sedimentary environments, and are characterised by shallow coastal slope gradients, making them sensitive to even modest changes in sea-level. The Shannon estuary is the largest river estuary in Ireland and is designated as a Special Area of Conservation (SAC) under the EU Habitats Directive (EU 1992) providing protection for listed habitats within it, including estuarine salt marsh. Trends in Shannon estuary tidal data from 1877 – 2004 suggest an average upward SLR trend of 4 - 5mm/yr over this period. A simple linear extension of this historical trend would imply that local SLR will be in the region of 40 - 45cm by 2100. However, this may underestimate actual SLR for the estuary by 2100, since it takes no account of predicted climate-driven global SLR acceleration (IPCC 2007) up to 2100

Logistics

Before World War II Naval Logistics was more of a theoreti­cal than a practical problem. Logistical support was considered a matter of routine by a majority of the officers of the Navy. In fact, the only logistic problems normally presented were those involved in fleet exercises and winter cruises

University of Strathclyde at TREC HARD

The motivation behind the University of Strathclyde's approach to this years HARD track was inspired from previous experiences by other participants, in particular research by [1], [3] and [4]. A running theme throughout these papers was the underlying hypothesis that a user's familiarity in a topic (i.e. their previous experience searching a subject), will form the basis for what type or style of document they will perceive as relevant. In other words, the user's context with regards to their previous search experience will determine what type of document(s) they wish to retrieve

A Quantitative Analysis of Response Elimination and Resurgence Using Rich, Lean, and Thinning Schedules of Alternative Reinforcement

A common approach to the treatment of instrumental problem behavior is the introduction of an acceptable alternative source of reinforcement. However, when alternative reinforcement is removed or reduced, the target behavior tends to relapse. The relapse of a target response following the removal of alternative reinforcement has been termed resurgence. Shahan and Sweeney developed a quantitative model of resurgence based on behavioral momentum theory that captures both the disruptive and strengthening effects of alternative reinforcement on the target response. The quantitative model suggests that although higher rates of alternative reinforcement result in faster response elimination, lower rates of alternative reinforcement result in less relapse when removed. The present study was designed to examine the possibility that good target response suppression and less relapse could be achieved by beginning with a higher (rich) rate of alternative reinforcement and gradually thinning it such that a lower (lean) rate of alternative reinforcement is ultimately removed. Furthermore, the data obtained were generated to provide insight into how thinning rates of alternative reinforcement might be incorporated into the quantitative model of resurgence. Results suggest that rich rates of alternative reinforcement were more effective than lean or thinning rates of alternative reinforcement at response suppression during treatment, but when alternative reinforcement was discontinued, the group that experienced rich rates exhibited a substantial increase. Although lean and thinning rates of alternative reinforcement were not as effective at response suppression during treatment as rich rates, they still resulted in substantial decreases in the target response. Furthermore, removal of lean rates of alternative reinforcement did not result in substantial increase in the target response. Advantages and disadvantages of rich, lean, and thinning alternative reinforcement rates are discussed with respect to target response suppression and sensitivity to the end of treatment, and an alternative response rate is discussed. Although a small modification to the quantitative model was able to similarly account for data produced by rich, lean, and thinning alternative reinforcement, as it currently stands the model is unable to account for the finding that alternative reinforcement may not always serve as a disruptor relative to a no alternative reinforcement control