Stop Event Research Articles

Differing approaches to analyse on-treatment cardiovascular events comparing daprodustat with darbepoetin: results from the ASCEND-ND trial

Abstract Background Hypoxia-inducible factor prolyl hydroxylase inhibitors (HIF-PHIs) represent a potential new therapeutic option to treat anaemia of chronic kidney disease (CKD). Purpose In the recent ASCEND-ND trial (NCT02876835)1, conducted in patients with anaemia of CKD not requiring dialysis, the HIF-PHI daprodustat was non-inferior to darbepoetin for cardiovascular (CV) events in the primary intention-to-treat analysis (HR 1.03; 95% CI 0.89, 1.19); however, a prespecified on-treatment analysis raised concerns about a higher risk of CV events associated with daprodustat compared to darbepoetin (HR 1.40; 95% CI 1.17, 1.68). Our analysis explored potential reasons to explain the differences between on-treatment and intention-to-treat analyses in ASCEND-ND. Methods Overall, 3872 patients were randomised to receive either oral daprodustat (daily) or darbepoetin alfa given weekly, every 2 weeks, or every 4 weeks in an open-label fashion (last dosing frequency for darbepoetin was 7% weekly, 15% every 2 weeks, and 78% every 4 weeks). Patients were followed for development of the composite CV outcome (all-cause death, first non-fatal myocardial infarction, or first non-fatal stroke). The prespecified on-treatment approach included CV events up to 28 days following the last non-zero dose date of randomised therapy (Figure 1). Post-hoc analyses used Cox regression models to assess the impact of different follow-up periods (indexed to last non-zero dose date, treatment stop (discontinuation) date, and dosing intervals) on the treatment effect estimate. Results Different definitions of “on-treatment” using alternative censoring approaches resulted in hazard ratios for the CV composite outcome for daprodustat vs. darbepoetin that ranged from 1.06 (95% CI 0.89, 1.27) censored at treatment stop date; 1.09 (95% CI 0.89, 1.33) censored at last non-zero dose date + dosing interval; 1.54 (95% CI 1.20, 1.97) censored at the last non-zero dose date (Figure 2). As a result of the differential dosing interval, the gap between the last non-zero dose date and CV event date was 15 [1 to 134] days in the daprodustat arm, and 35 [13 to 134] days prior in the darbepoetin arm. This resulted in identical patients (i.e., identical treatment stop dates and event dates) being more likely to count as “on-treatment” in the daprodustat arm (Figure 1). This artefactual difference was not observed in analyses that were indexed to the treatment stop date, nor in analyses that accounted for the different dosing intervals for darbepoetin. Conclusion In the ASCEND-ND trial, different dosing frequencies introduced longer intervals between the last non-zero dose date and date of CV outcomes in the darbepoetin arm, compared with daprodustat. This artefact led to inappropriate undercounting of CV events in the darbepoetin arm. Accounting for the differential intervals resulted in neutral effect estimates, which were consistent with those observed with intention-to-treat approaches. Funding Acknowledgement Type of funding sources: Private company. Main funding source(s): ASCEND-ND was funded by GlaxoSmithKline

The interplay between dockless bikeshare and bus for small-size cities in the US: A case study of Ithaca

As another mode of shared transportation, bikeshare can substitute or complement public transit. Prior studies mainly relied on self-reported survey data or aggregated station-level data from docked bikeshare systems, and their conclusions and implications were focused on large cities. It is largely unknown how and to what extent a dockless bikeshare system complements or substitutes public transit, especially in small cities. This study was set to measure the interplay between Lime dockless bikeshare and bus service in Ithaca, NY – a typical small-size college town – and its environs. By joining about 3.42 million records of bus stop data and 102 thousand Lime bikeshare trip data from 2019, two types of Bikeshare-Bus-Linkage (BBL) trips were identified, namely (1) the first-mile trip where a user rides a Lime to board a bus, and (2) the last-mile trip where a user bikes to their destination after alighting a bus. BBL trips were identified using a spatiotemporal proximity framework based on two important parameters: the catchment radius and the time window between a bus stop event and a Lime trip. Different values were tested with a sensitivity analysis, and the parameters were finally set at 100 ft. and 5 min. As such, 3026 BBL trips were identified, which was 3% of total Lime ridership or 0.1% of total bus ridership. Our findings indicated that Lime provided useful first- and last-mile transfers to bus service for commuters. The complementary effect was particularly strong in the urban core and with transit development and employment land use areas. Moreover, in the morning peak, there were more first-mile trips from residential areas to bus stops in the urban core, while in the evening peak more last-mile trips started from bus stops in the urban core to residential areas. Based on the unique first-mile and last-mile trip patterns identified, policy implications and recommendations for bikeshare operators, local government, transit agencies, and transportation policymakers were discussed to better integrate bikeshare and public transit.

Purification effect evaluation of the designed new volcanic soil adsorption material containing bioreactor for eutrophic water treatment.

The purpose of this study was to investigate the purification effect of a new adsorption material containing bioreactor and the critical role of viable but non-culturable (VBNC) bacteria in a eutrophication ecosystem. Major water quality parameters of the prepared eutrophic water were determined, and the microbial community was analyzed during 2 years. The results showed that removal rates of total phosphorus (TP), total nitrogen (TN), chlorophyll-a (Chl-a), and chemical oxygen demand (COD) were 90.7-95.9%, 84.5-92.4%, 87.9-95.8%, and 68.3-82.7%, respectively, indicating the high efficiency of the bioreactor in the eutrophic water treatment. Although the bioreactor had been operated for 2 years, water from the treatment group was much clearer and odorless than from the control group, exhibiting the long service life of the bioreactor. Stopping operation in August caused significant decrease of the removal rates of major water quality parameters (p < 0.05). This operational stop event and high temperature in summer exerted a dual effect on the bioreactor, whereas the impact could be minimized when the bioreactor was running. Moreover, the total bacteria under +Rpf (active resuscitation-promoting factor) treatment were higher than under -Rpf (inactive resuscitation-promoting factor) treatment, implying that Rpf could resuscitate VBNC bacteria in the eutrophication ecosystem. Nine strains of VBNC bacteria were isolated based on the BLAST results of the 16S rRNA gene. Also, these bacteria might contribute to the eutrophic water treatment based on their functions of phosphorus collecting and denitrification. These results provided new insights for engineering technology innovations, and consequently these findings had benefits in eutrophic water treatment.

Using bus critical driving events as surrogate safety measures for pedestrian and bicycle crashes based on GPS trajectory data

Pedestrian and bicycle safety is a key component in traffic safety studies. Various studies were conducted to address pedestrian and bicycle safety issues for intersections, road segments, etc. However, only a few studies investigated pedestrian and bicycle safety for bus stops, which usually have a relatively larger volume of pedestrians and bicyclists. Moreover, traditional reactive safety approaches require a significant number of historical crashes, while pedestrian and bicycle crashes are usually rare events. Alternatively, surrogate safety measures could proactively evaluate traffic safety status when crash data are rare or unavailable. This paper utilized critical bus driving events extracted from GPS trajectory data as pedestrian and bicycle surrogate safety measures for bus stops. A city-wide trajectory data from Orlando, Florida was used, which contains around 300 buses, 6,700,000 GPS records, and 1300 bus stops. Three critical driving events were identified based on the buses’ acceleration rates and stop time; hard acceleration, hard deceleration, and long stop. The relationships between critical driving events and crashes were examined using Spearman’s rank correlation coefficient. All three events were positively correlated with pedestrian and bicycle crashes. Long stop event has the highest correlation coefficient, followed by hard acceleration and hard deceleration. A Bayesian negative binomial model incorporating spatial correlation (Bayesian NB-CAR) was built to estimate the pedestrian and bicycle crash frequency using the generated events. The results were consistent with the correlation estimation. For example, hard acceleration and long stop events were both positively related to pedestrian and bicycle crashes. Moreover, model evaluation results indicated that the proposed Bayesian NB-CAR outperformed the standard Bayesian negative binomial model with lower Watanabe-Akaike Information Criterion (WAIC) and Deviance Information Criteria (DIC) values. In conclusion, this paper suggests the use of critical bus driving events as surrogate safety measures for pedestrian and bicycle crashes, which could be implemented in a proactive traffic safety management system.

Structural analysis on mild-steel and aluminium brake disk for application on belt conveyor

A disk brake system has three essential functions, namely, reducing the moving conveyor speed, preserving its steady downhill speed and stopping the conveyor fully during normal or emergency operation. There has been a persistent demand in recent years for light weight disks with highly efficient energy-absorbing structures and materials in the overall conveyor system. This aspiration has led to experimental work in attempt to use various materials for engineering designs. In this article, a rotating annular disc subjected to in-plane frictional loads is analytically modelled on the brake system. In order to obtain modal properties of breaking for inputs into the finite element model, the experimental modal test of disc brake device free under free boundary conditions is performed. The goal of this research is to recognize various properties that may in future enable us to optimize working parameters and increase braking system efficiency. The findings will enable us to achieve the optimal functionality of this structure to improve the operational disc life or performance. The aim of this document is to examine stress concentration, structural deformation and brake disk contact pressure during a single braking stop event using ANSYS 19.2 academic finite element software. This research therefore provides an important guide to the design and engineering of the brake disk and the brake pad. Structural and stress analysis are therefore preferred to pick the lightweight material for improved performance. Consequently, the lightweight material may be recommended to reduce the conveyor working load and preserve operational energy consumption, provided that light weight will satisfy working duty requirements. Comparing the results achieved with those of the technical literature, the simulation is satisfactory.

Beyond simulation — Extracurricular volunteering in nursing education: A focus group

BackgroundA reduction in clinical placement hours has seen alternative teaching methods being explored in nursing education in Australia. The use of simulated patients in academic laboratories is highly utilised, however, may still be limiting learning opportunities. ObjectiveThe objective of this research was to describe the learning experiences of nursing students who participated in supervised extracurricular, volunteering opportunities during their nursing studies. DesignA descriptive qualitative design was used to discover and understand learning experiences of a volunteering encounter, described from the nursing student perspective. SettingThe Pit Stop men’s health check program is a collaboration of local health organisations, volunteering their time to provide free health checks at a farming Field Day event in regional Victoria, Australia. ParticipantsTwelve second year undergraduate nursing students volunteered at the 2019 Pit Stop event, over a four day period and outside their normal study requirements. Seven volunteers then participated in post event research, sharing experiences and providing feedback. MethodsOne semi-structured focus group interview was conducted at University campus, using reflective and open ended questioning. Interviews were audio recorded and transcribed. Thematic analysis identified common themes. ResultsStudents unanimously recommended the real life learning experiences and reported an increased confidence and competence in basic communication and clinical skills, not always provided in the simulated environment of the academic laboratory. Their motivation to attend was driven by wanting more real life contact with patients, having time to practice skills and experience diversity within their practice. Students also recommended future volunteering ideas that would potentially provide additional learning opportunities. ConclusionsExperiential learning such as simulation is highly valued in current nursing education, however, students still crave the real life learning experiences from working with human patients. With limited clinical exposure currently offered to students within nursing education programs, additional opportunities such as supervised volunteering may be worth considering when preparing confident and competent nurse graduates.

Validation of combined analytical methods to predict slip in cylindrical roller bearings

This paper presents a combination of models that together calculate the cage and roller speeds of a cylindrical roller bearing. The models consider elastohydrodynamic lubrication and contact elasticity between the roller and raceway, roller centrifugal forces, hydrodynamic lubrication at the cage pocket, and frictional forces. Using these models, the predicted cage and roller speeds and the extent of slip are compared to measurements acquired on cylindrical roller bearings in a commercial gearbox in steady-state and transient operating conditions of a wind turbine. In steady-state conditions at low wind speeds and low lubricant temperatures, cage and roller slip up to 60% occur in the loaded zone of the bearing. In the unloaded zone, up to 80% roller slip occurs. Cage and roller slip then decrease as the lubricant temperature and wind speed increases. In general, the analytical model results match experimental measurements within 10% for lubricant temperatures above 40°C and wind speeds over 10 meters per second. The analytical model is further evaluated during a transient start-up event and highly dynamic emergency stop event and also used to examine changes in the bearing design or lubricant properties. Roller and cage slip in cylindrical bearings is a combined effect of the bearing design, applied load, shaft speed, and lubricant properties and temperature, and can be quickly evaluated with the combined analytical models.

Cardioprotective Effect of Dexrazoxane in Patients with HER2-Positive Breast Cancer Who Receive Anthracycline Based Adjuvant Chemotherapy Followed by Trastuzumab

PurposeWe intended to determine whether dexrazoxane (DZR) is cardioprotective during administration of adjuvant anthracycline-based chemotherapy followed by a 1-year trastuzumab treatment.MethodsThe medical records of 228 patients who underwent surgical resection and received adjuvant chemotherapy with trastuzumab for human epidermal growth factor receptor type 2 (HER2)-positive breast cancer between January 2010 and December 2014 were reviewed. Approximately 25% of patients received DZR prior to each administration of doxorubicin during doxorubicin with cyclophosphamide (AC) chemotherapy. DZR was not administered during the 1-year trastuzumab maintenance period. Rates of cardiac events (reduction in left ventricular ejection fraction [LVEF] by 10% or more; reduction in absolute LVEF to <45%) and cardiac event-free duration (CFD) were examined. The trastuzumab interruption rate was also assessed.ResultsTwelve percent of patients experienced a cardiac event. Repeated-measures analysis of variance for ejection fraction revealed a significant main effect of time, and a significant group (DZR)×time interaction. The group treated with adjuvant chemotherapy and DZR experienced significantly lower frequencies of cardiac events than the adjuvant chemotherapy only group. In multivariate analysis, DZR administration was associated with significantly fewer cardiac events. Moreover, DZR administration was an independent good prognostic factor for CFD. Only one patient (2.3%) experienced early interruption of trastuzumab in the adjuvant chemotherapy with DZR group due to cardiac toxicity, whereas 10 patients (7.6%) experienced a trastuzumab stop event in the adjuvant chemotherapy only group.ConclusionDZR is cardioprotective in HER2-positive breast cancer patients who received adjuvant chemotherapy with trastuzumab. A large cohort randomized trial is needed to determine if DZR has an effect on trastuzumab interruption and completion of 12-month trastuzumab. Because cardiac toxicity has a significant negative effect on trastuzumab maintenance and quality of life, DZR administration could be considered concomitantly with anthracycline-based adjuvant chemotherapy with trastuzumab.

Thermal and structural analysis of disc brake assembly during single stop braking event

An automobile disc brake system is used to perform three basic functions, i.e. to reduce speed of a vehicle, to maintain its speed when travelling downhill and to completely stop the vehicle. During these braking events, the disc brake may suffer from structural and wear issues. It is quite sometimes that the disc brake components fail structurally and/or having severe wear on the pad. Thus, this paper aims to determine disc temperature and to examine stress concentration, structural deformation and contact pressure of brake disc and pads during single braking stop event by employing commercial finite-element software, ANSYS. The paper also highlights the effects of using a fixed calliper, different friction coefficients and different speeds of the disc on the stress concentration, structural deformation and contact pressure of brake disc and pads, respectively. The thermal-structural analysis is then used with coupling to determine the deformation and the Von Mises stress established in the disc, the contact pressure distribution in pads.

Crowdsending based public transport information service in smart cities

Thanks to the development of technology and the emergence of intelligent services smart cities promise to their inhabitants enhanced perception of city life. For example, a live timetable service of public transportation can increase the efficiency of travel planning substantially. However, its implementation in a traditional way requires the deployment of some costly sensing and tracking infrastructure. Mobile crowdsensing is an alternative, when the crowd of passengers and their mobile devices are used to gather data for almost free of charge. In this paper, we put the emphasis on the introduction of our crowdsensing based public transport information service, what we have been developing as a prototype smart city application. The front-end interface of this service is called TrafficInfo. It is a simple and easy-to-use Android application which visualizes real-time public transport information of the given city on Google Maps. The lively updates of transport schedule information relies on the automatic stop event detection of public transport vehicles. TrafficInfo is built upon our Extensible Messaging and Presence Protocol (XMPP) based communication framework what we designed to facilitate the development of crowd assisted smart city applications. The paper introduces shortly this framework, than describes TrafficInfo in detail together with the developed stop event detector.

Structural and Contact Analysis of Disc Brake Assembly During Single Stop Braking Event

The aim of this paper is to examine stress concentration, structural deformation and contact pressure of brake disc and pads during single braking stop event by employing commercial finite element software, ANSYS. The paper also highlights the effects of using a fixed caliper, different friction coefficients and different speeds of the disc on the stress concentration, structural deformation and contact pressure of brake disc and pads, respectively. Results from the investigation could provide a better explanation of the variation in contact pressure distribution and in turn squeal generation. Thus, this study provides effective reference for design and engineering application of brake disc and brake pad.

Structural and Contact Analysis of Disc Brake Assembly during Single Stop Braking Event

An automobile disc brake system is used to perform three basic functions, i.e. to reduce speed of a vehicle, to maintain its speed when travelling downhill and to completely stop the vehicle. During these braking events, the disc brake may suffer of structural and wear issues. It is quite sometimes that the disc brake components fail structurally and/or having severe wear on the pad. Thus, this paper aims to examine stress concentration, structural deformation and contact pressure of brake disc and pads during single braking stop event by employing commercial finite element software, ANSYS. The paper also highlights the effects of using a fixed caliper, different friction coefficients and different speeds of the disc on the stress concentration, structural deformation and contact pressure of brake disc and pads, respectively. Results from the investigation could provide a better explanation of the variation in contact pressure distribution and in turn squeal generation. Thus, this study provides effective reference for design and engineering application of brake disc and brake pad.

Tests on the SNS Rotating Target Design at the RTFT (ESS BILBAO)

Efficient cooling of the target material is a key issue in the design of a spallation target. The aim of the RTFT (Rotating Target Flow Test) facility at ESS Bilbao (Zamudio, Spain) is the characterization of coolant flow in rotating targets. Maps of flow velocity along cooling channels are obtained with PIV (Particle Image Velocimetry) techniques. Tests are performed with water flowing at up to 30 l/s and 5bar, for different disk rotation rates, and are used to evaluate target designs in terms of potential flow instabilities and adverse effects -such as flow stagnation and recirculation-, to benchmark calculation and simulation models, and to assess final target designs.ESS Bilbao and SNS have recently performed a first test campaign on a full scale mockup of the latest SNS design for a 1.5MW rotating target. Tests included runs at several operation conditions, plus an emergency stop simulation, for observation of the water flow evolution in a pump sudden stop event.

Real-time One-dimensional Brain-Computer Interface (BCI) Using Prefrontal Cortex Neuronal Activities of Rats

The aim of this study is to verify the feasibility of control of one-dimensional (1-D) rotating machine using neural activities of Prefrontal cortex (PFC) in a BCI system. In this study, adult male Sprague-Dawley rats received bilateral implantation of recording micro-electrodes in PFC area. The spontaneous activities of a pair of PFC neurons of water-deprived rats were encoded and converted through a triple-step threshold comparator algorithm to three commands for one-dimensional movement control of a robotic wheel for accessing water. Averaged activities of two PFC neurons were quantized in every 200 ms to four ranges of activities around the mean firing rates (±0.5 SD) and were converted to four values. After comparison of the values of two chosen neuron units, direction and speed of rotation were decided. Rats were trained to complete one-dimensional control task to obtain water reward. The results indicated the percentage of stop event increased alone with more training. Different brain activity significantly influenced total water-drinking duration and non-water-drinking duration. Events generated from neuronal activity differed according to variant experimental sessions. Correlation between two signal units impacted controlling performance. Overall, the results of this study suggest that rats were able to manipulate the 1-D BCI system by differentially modulating PFC single neuron activities according to different circumstances. words: brain-computer interface, prefrontal cortex, rat, one-dimensional, single neu

Searching for a top-squark–top-squark pair sample from top counting experiments at hadron colliders

The light stop pair if produced in hadron colliders and decaying through the likely decay chain stop->chargino + b followed by chargino->neutralino + f f', can mimic closely a top quark event when the mass of the stop is close to that of the top quark. Because of the much lower production rate, the stop event can be buried under the top quark event sample. In order to uncover the stop event, specific selection cuts need to be applied. Through Monte Carlo simulation with suitable kinematic cuts, we found that such stop event can be extracted from the top quark sample and detected by the top quark counting experiments in the upcoming upgraded Tevatron and LHC. However, because of the small statistics of the Run 1 of the Tevatron, the stop signal remains hidden at Run 1.

252Cf-plasma desorption mass spectrometry multistop time digitizer

A multistop time digitizer is described which was designed specifically for 252Cf-plasma desorption time-of-flight mass spectrometry. The digitizer is a high resolution time intervalometer capable of measuring the times of a number of stop events following a common start. A resolution of 78.125 ps is achieved. The time range can be varied from 5 ms to 320 ms in 16 steps. Stop event processing time takes less than one microsecond, enabling high resolution measurements of closely spaced bursts of events. The digitizer consists of the following three modules. A clock module provides the accurate time reference including a precision time calibrator. An analog module contains a special tandem stretcher by which the high resolution and low differential nonlinearity are achieved. A digital module comprises the counting, logic and interface circuits. Up to four complete digitizers can be housed in and powered by a standard CAMAC crate.

Interaction between correlated and uncorrelated time-interval distributions in start-stop time-to-amplitude converters

An interaction between correlated and uncorrelated time-interval distributions in start-stop time-to-amplitude converters was observed. Investigation of the effect under controlled conditions showed the interaction to be dependent on the efficiency of the stop event detector. A rapidly convergent iteration method was developed to remove the uncorrelated events from the time-interval distribution. The method was tested on both experimentally and theoretically generated data.