302 research outputs found
Displacement demand for nonlinear static analyses of masonry structures: Critical review and improved formulations
This paper discusses different formulations for calculating earthquakeâinduced displacement demands to be associated with nonlinear static analysis procedures for the assessment of masonry structures. Focus is placed on systems with fundamental periods between 0.1 and 0.5 s, for which the inelastic displacement amplification is usually more pronounced. The accuracy of the predictive equations is assessed based on the results from nonlinear timeâhistory analyses, carried out on singleâdegreeâofâfreedom oscillators with hysteretic forceâdisplacement relationships representative of masonry structures. First, the study demonstrates some limitations of two established approaches based on the equivalent linearization concept: the capacity spectrum method of the Dutch guidelines NPR 9998â18, and its version outlined in FEMA 440, both of which overpredict maximum displacements. Two codified formulations relying on inelastic displacement spectra are also evaluated, namely the N2 method of Eurocode 8 and the displacement coefficient method of ASCE 41â17: the former proves to be significantly unconservative, while the latter is affected by excessive dispersion. A nonâiterative procedure, using an equivalent linear system with calibrated optimal stiffness and equivalent viscous damping, is then proposed to overcome some of the problems identified earlier. A recently developed modified N2 formulation is shown to improve accuracy while limiting the dispersion of the predictions
New Medicines in Wales:The All Wales Medicines Strategy Group (AWMSG) Appraisal Process and Outcomes
Continuous infusion of an agonist of the tumor necrosis factor receptor 2 in the spinal cord improves recovery after traumatic contusive injury.
AimThe activation of the TNFR2 receptor is beneficial in several pathologies of the central nervous system, and this study examines whether it can ameliorate the recovery process following spinal cord injury.MethodsEHD2-sc-mTNFR2 , an agonist specific for TNFR2, was used to treat neurons exposed to high levels of glutamate in vitro. In vivo, it was infused directly to the spinal cord via osmotic pumps immediately after a contusion to the cord at the T9 level. Locomotion behavior was assessed for 6Â weeks, and the tissue was analyzed (lesion size, RNA and protein expression, cell death) after injury. Somatosensory evoked potentials were also measured in response to hindlimb stimulation.ResultsThe activation of TNFR2 protected neurons from glutamate-mediated excitotoxicity through the activation of phosphoinositide-3 kinase gamma in vitro and improved the locomotion of animals following spinal cord injury. The extent of the injury was not affected by infusing EHD2-sc-mTNFR2 , but higher levels of neurofilament H and 2', 3'-cyclic-nucleotide 3'-phosphodiesterase were observed 6Â weeks after the injury. Finally, the activation of TNFR2 after injury increased the neural response recorded in the cortex following hindlimb stimulation.ConclusionThe activation of TNFR2 in the spinal cord following contusive injury leads to enhanced locomotion and better cortical responses to hindlimb stimulation
seafloor integrity of the mar piccolo basin southern italy quantifying anthropogenic impact
ABSTRACTThe Mar Piccolo Basin is a coastal brackish marine ecosystem located along the northern coast of the Gulf of Taranto (Southern Italy). Despite the ecological relevance of the area (Site of Community Importance IT9130004, Regional Reserve 'Palude La Vela' EUAP1189), the entire basin is subjected to intensive human usage. The main activities include extensive mussel farming, important industrial activities, a military harbor and densely populated shores. The goal of our study was to spatially quantify human pressure within the basin and its relationship with biocoenoses. A broad set of data was integrated including acoustic remote data (obtained using a multibeam echosounder and side scan sonar devices), direct observations obtained by SCUBA diving and from a trawled camera, an orthophoto and ESRIÂź Imagery Basemap. At least eight categories of anthropogenic infrastructure and marks of past and present-day human activities were identified within the Mar Piccolo Basin water column and on the seafloor...
Changes in suspected adverse drug reaction reporting via the Yellow Card scheme in Wales following the introduction of a National Reporting Indicator
AIMS: This study aimed to assess the impact of a National Reporting Indicator (NRI) on rates of reporting of suspected adverse drug reactions using the Yellow Card scheme following the introduction of the NRI in Wales (UK) in April 2014. METHODS: Yellow Card reporting data for general practitioners and other reporting groups in Wales and England for the financial years 2014â15 (study period 1) and 2015â16 (study period 2) were obtained from the Medicines and Healthcare Products Regulatory Agency and compared with those for 2013â14 (preâNRI control period). RESULTS: The numbers of Yellow Cards submitted by general practitioners in Wales were 271, 665 and 870 in the control period, study period 1 and study period 2, respectively. This is equivalent to an increase of 145% in study period 1 and 221% in study period 2 compared with the 12âmonth control period (2013â14). Corresponding increases in England were 17% and 37%, respectively (PÂ <â.001 chiâsquared test). The numbers of Yellow Cards submitted by other groups in Wales were 906, 795 and 947 in each of the study periods. CONCLUSIONS: Introduction of the NRI corresponded with a significant increase in the number of Yellow Cards submitted by general practitioners in Wales. General practitioner reporting rates continued to increase year on year through to 2018â19 with the NRI still in place. No concomitant change was found in reporting rates by other groups in the health boards in Wales
The All Wales Medicines Strategy Group: 18âyears' experience of a national medicines optimisation committee
Aims
To review the medicines optimisation activities of the All Wales Medicines Strategy Group (AWMSG), a committee established in 2002 to advise the Welsh Government on âall matters related to prescribingâ. Although AWMSG conducts other activities (e.g., health technology appraisal for medicines), we focus here on its role in advising on medicines optimisation.
Methods
Prescribing indicators have been used in Wales to measure change, together with data on volumes and costs of medicines dispensed. A range of improvement strategies have been categorised under the âfour Esâ, namely educational initiatives, economic incentives, âengineeringâ and âenforcementâ.
Results
AWMSG has helped health professionals in NHS Wales to reduce harm and waste, and to reduce inappropriate local or regional duplication and variation. Specific initiatives include the achievement of major cost savings by supporting increased generic prescribing and an âinvest to saveâ approach related to prescribing of hypnotics and tranquillisers, non-steroidal anti-inflammatory drugs (NSAIDs) and proton pump inhibitors. AWMSG also successfully commissioned the introduction of a single national in-patient medication chart for Wales in 2004. Ongoing priorities include a focus on reducing prescribing of certain medicines deemed âlow value for prescribingâ and on optimising the use of biosimilar medicines.
Conclusions
Since 2002, AWMSG has acted as a national medicines optimisation committee in Wales. From the outset, pharmacists and clinical pharmacologists have collaborated closely and shared their complementary expertise to make a much greater contribution to the safe, effective and cost-effective use of medicines than either group could have achieved by working separately
Non-perforated peptic ulcer disease: multidetector CT findings, complications, and differential diagnosis
Despite availability of effective therapies, peptic ulcer disease (PUD) remains a major global disease, resulting from a combination of persistent Helicobacter pylori infection and widespread use of nonsteroidal anti-inflammatory drugs. Albeit endoscopy definitely represents the mainstay diagnostic technique, patients presenting to emergency departments with unexplained abdominal pain generally undergo multidetector CT as an initial investigation. Although superficial ulcers generally remain inconspicuous, careful multiplanar CT interpretation may allow to detect deep ulcers, secondary mural and extraluminal signs of peptic gastroduodenitis, thereby allowing timely endoscopic verification and appropriate treatment. This pictorial essay aims to provide radiologists with an increased familiarity with CT diagnosis of non-perforated PUD, with emphasis on differential diagnosis. Following an overview of current disease epidemiology and complications, it explains the appropriate CT acquisition and interpretation techniques, and reviews with several examples the cross-sectional findings of uncomplicated PUD. Afterwards, the CT features of PUD complications such as ulcer haemorrhage, gastric outlet obstruction, biliary and pancreatic fistulisation are presented.
Teaching points
Gastric and duodenal peptic ulcers are increasingly caused by nonsteroidal anti-inflammatory drugs
Multiplanar CT interpretation allows detecting deep ulcers and secondary signs of gastroduodenitis
CT diagnosis of uncomplicated peptic disease relies on direct and indirect signs
Currently the commonest complication, haemorrhage may be treated with transarterial embolisation
Other uncommon complications include gastric outlet obstruction and biliopancreatic fistulisation
Macroelement Numerical Simulation of the Seismic Response of a Timber-Retrofitted Masonry Pier
In the North-East part of The Netherlands, induced seismicity due to gas extraction is affecting a local building stock consisting mainly of unreinforced masonry (URM) houses not designed for earthquake resistance. Experimental and numerical studies conducted at EUCENTRE, Pavia (Italy), have demonstrated that buildings with URM cavity-walls structural systems are among the most vulnerable existing Dutch construction typologies. A light and reversible retrofit system made of timber frames and oriented-strands boards was then designed and tested to increase the in-plane and out-of-plane capacities of masonry piers and to enhance their connections with the floor diaphragms. The development of modelling approaches able to simulate the influence of the retrofit system is of fundamental importance for future applications to real-case existing buildings and for vulnerability studies on different building stocks. Based on two quasi-static in-plane shear-compression tests on two full-scale masonry piers, one in bare and one in retrofitted configuration, a specific macroelement was calibrated to simulate the bare pier lateral response and the effects of the retrofit on the in-plane flexural and shear capacities. This paper discusses the adopted modelling strategies and the comparison between numerical and experimental results
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