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The floor-to-floor axial shortening of vertical load-bearing elements is an important factor in the design and construction of high-rise buildings. Contractors need to allow for the expected final compression of columns and walls due to superimposed load, concrete creep and shrinkage, particularly when installing finishes and partitions in lower floors, while the building has not yet been completed. An added complication arises from the differential shortening between elements of different stiffness. This axial shortening is predicted by designers using empirical models, in advance of construction. However, in practice, the shortening at every level cannot be measured continuously using traditional surveying measurement techniques during construction. Therefore, a monitoring system using distributed fibre optic sensors (DFOS) measuring strain and temperature, is being installed during the construction of Principal Tower, a 50-storey reinforced concrete building in London. DFOS sensors are being embedded inside two columns and two walls as the construction progresses. Using the strain and temperature data acquired from this system, the axial deformation relative to the ground level can be calculated along the whole height of the completed elements, at any time during the construction. Thus, the engineers and contractors are able to verify their predictions and adjust their assumptions if necessary. A selection of the data acquired during the construction of the first 17 levels of the building is presented. These data have shown that the amount of shortening experienced by a member is influenced by the member’s stiffness and size. The monitoring data have also revealed that thermal movement has a significant effect on the overall axial displacement of the building.

A novel approach is being used to measure the progressive axial shortening of key structural elements of Principal Tower, a 50-storey reinforced concrete building in London, as it is being built. Distributed fibre optic sensor (DFOS) cables are embedded inside two columns and two core walls, from which the axial strain profile can be measured along the whole height of the constructed elements. Measurements are being taken regularly throughout the construction process, making it possible to observe the change in strain, and thus the axial shortening, within these elements, at any stage of the construction. This helps the design engineers and contractor verify the predicted differential shortening and adjust the column height presets if necessary. The purpose of this paper is to describe the monitoring system and to present initial data recorded from the first five levels of the building., This research has been made possible through funding under EPSRC grant EP/N021614/1 and Innovate UK grant 920035, as well as funding by WSP, Multiplex Construction and Careys.

Behavioural studies indicate that cannabinoid receptors are implicated in cocaine addiction. The synaptic underpinning of cocaine-cannabinoid receptor interaction is however, obscure. We have studied electrophysiologically the sensitivity of cannabinoid receptors modulating synaptic transmission in the striatum of rats exposed to cocaine. One-day treatment with cocaine did not modify the synaptic response to HU210, a cannabinoid CB1 receptor agonist. Seven days cocaine-treatment, conversely, caused conditioned place preference, and sensitized striatal GABAergic synapses to the presynaptic effect of cannabinoid CB1 receptor stimulation. The cannabinoid receptor-induced modulation of glutamate transmission was unaltered by cocaine. Furthermore, the effects of chronic cocaine on cannabinoid-mediated regulation of striatal GABA synapses were attenuated one week after the discontinuation of cocaine, and absent two weeks later, indicating the progressive reversibility of the adaptations of cannabinoid system during abstinence of drug consumption. Our data support the concept that modulation of cannabinoid receptors might be useful against drug abuse. Behavioural studies indicate that cannabinoid receptors are implicated in cocaine addiction. The synaptic underpinning of cocaine-cannabinoid receptor interaction is however, obscure. We have studied electrophysiologically the sensitivity of cannabinoid receptors modulating synaptic transmission in the striatum of rats exposed to cocaine. One-day treatment with cocaine did not modify the synaptic response to HU210, a cannabinoid CB1 receptor agonist. Seven days cocaine-treatment, conversely, caused conditioned place preference, and sensitized striatal GABAergic synapses to the presynaptic effect of cannabinoid CB1 receptor stimulation. The cannabinoid receptor-induced modulation of glutamate transmission was unaltered by cocaine. Furthermore, the effects of chronic cocaine on cannabinoid-mediated regulation of striatal GABA synapses were attenuated one week after the discontinuation of cocaine, and absent two weeks later, indicating the progressive reversibility of the adaptations of cannabinoid system during abstinence of drug consumption. Our data support the concept that modulation of cannabinoid receptors might be useful against drug abuse.

Over the last two decades, the role played by phytocannabinoids and endocannabinoids in medicine has gained increasing interest in the scientific community. Upon identification of the plant compound Δ(9)-tetrahydrocannabinol (THC) and of the endogenous substance anandamide (AEA), different methodological approaches and innovative techniques have been developed, in order to evaluate the content of these molecules in various human matrices. In this review, we discuss the analytical methods that are currently used for the identification of phytocannabinoids and endocannabinoids, and we summarize the benefits and limitations of these procedures. Moreover, we provide an overview of the main biological matrices that have been analyzed to date for qualitative detection and quantitative determination of these compounds.