Articles de revues : « Measurement burst design »

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Rast, Philippe, Stuart W. S. MacDonald et Scott M. Hofer. « Intensive Measurement Designs for Research on Aging ». GeroPsych 25, n^o 2 (janvier 2012) : 45–55. http://dx.doi.org/10.1024/1662-9647/a000054.

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Intensive measurement burst designs permit analysis of behavioral and biological processes as they unfold over short and long periods of time and providing the opportunity to identify change from an individual’s normative level of functioning. The measurement burst design permits statistical decomposition of short-term variation and learning effects that overlay normative aging and provide stronger bases for detecting accelerated change due to pathological processes. We provide an overview of design features and analysis of measurement burst data in Project MIND. The objective of intensive measurement designs is to obtain greater resolution of processes of interest that permit reliable and sensitive assessments of functioning and change in functioning and of key determinants underlying short-term variation and long-term aging and health-related change.

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Oravecz, Zita, Nelson Roque et Martin Sliwinski. « Bayesian Modeling of Cognitive Impairment in the Presence of Retest Effects ». Innovation in Aging 4, Supplement_1 (1 décembre 2020) : 566. http://dx.doi.org/10.1093/geroni/igaa057.1870.

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Abstract Diagnosing the early onset of neuropathologies, such as mild cognitive impairment (MCI), requires repeated evaluation of cognitive skills several times per year -- a measurement design known as a “burst design.” Detecting the often subtle cognitive decline in the presence of retest effects requires careful statistical modeling. The double exponential model offers a modeling framework to account for retest gains across measurement bursts, as well as warm-up effects within a burst, while quantifying change across bursts in peak performance. This talk highlights how a Bayesian multilevel implementation of the double exponential model allows for flexible extensions of this framework in terms of accommodating different timescales (nesting) and person-level predictors and drawing intuitive inferences on cognitive change with Bayesian posterior probabilities. We will use reaction time data to show how individual differences in asymptotic performance and change can be related to predictors such as age and MCI status. Part of a symposium sponsored by the Measurement, Statistics, and Research Design Interest Group.

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Alessandri, Guido, Evelina De Longis et Gianluca Cepale. « Emotional inertia emerges after prolonged states of exhaustion : Evidences from a measurement burst study ». Motivation and Emotion 45, n^o 4 (20 avril 2021) : 518–29. http://dx.doi.org/10.1007/s11031-021-09884-4.

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AbstractExhaustion refers to the feeling of ongoing loss of emotional, physical and cognitive resources. The present study draws on the Conservation of Resources Theory to examine the relationship between chronic exhaustion and negative emotional inertia among 206 employees (aged between 19 and 50 years; M = 21.03; SD = 2.98), in a naturalistic setting. To this purpose, we used a measurement burst design with two intensive bursts—spaced 1 month apart—by repeatedly sampling exhaustion and negative affect with 18 daily diaries (a morning and an evening assessment each day) per burst. After controlling for potential confounders, results showed that exhaustion at Burst 1 predicted negative emotional inertia at Burst 2, and not the other way around. These findings advance the knowledge on the relationship between exhaustion and negative emotional inertia by providing further insights on the likely direction of causality between study variables, that is from exhaustion to inertia (but not vice versa). Practical implication, limitations, and directions for future research are also discussed.

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Harrington, Karra, Nelson Roque et Jacqueline Mogle. « Approaches for Modeling of Intensive Longitudinal Data to Understand Cognitive Aging ». Innovation in Aging 4, Supplement_1 (1 décembre 2020) : 565. http://dx.doi.org/10.1093/geroni/igaa057.1867.

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Abstract Understanding age-related change in cognition and identification of pathological changes requires sensitive and valid measurement of cognitive performance across time. Technological advances, such as ambulatory assessment of cognition using smartphones, have enabled intensive longitudinal methods where data is collected with many measurements over time. Our research group has developed novel ambulatory assessments that provide reliable, sensitive, and ecologically valid measurement of cognition across multiple timescales; from momentary changes to change across years. This symposium will present a spectrum of approaches to analysis of intensive longitudinal data that can inform models of cognitive aging. All three presentations will draw on data from measurement burst studies that apply our ambulatory cognitive assessment methods in community-based samples (i.e., systematically recruited in the Bronx, New York). For each measurement burst, participants undergo assessment consisting of brief surveys and cognitive tests via smartphone, up to 7 times per day across 14 days. Oravecz et al. will discuss the application of a Bayesian multilevel implementation of the double exponential model to account for retest effects while quantifying change in peak cognitive performance across time. Kang et al., will demonstrate a growth curve modeling approach for assessing the effects of between-person variables (i.e., loneliness) on change in cognition across measurement bursts. Harrington et al., will demonstrate a model-based cluster analysis approach, leveraging ambulatory assessments of subjective and objective cognitive function to unpack latent groups as a function of age and loneliness. Measurement, Statistics, and Research Design Interest Group Sponsored Symposium.

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Kang, Jee-eun, Karra Harrington et Martin Sliwinski. « Loneliness and Cognitive Functioning Over Time : Using Ambulatory Cognitive Assessment ». Innovation in Aging 4, Supplement_1 (1 décembre 2020) : 566. http://dx.doi.org/10.1093/geroni/igaa057.1869.

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Abstract Loneliness has been investigated as a risk factor for cognitive health, but results were inconsistent. This study used three measurement bursts of ambulatory cognitive assessment to determine whether loneliness affects longitudinal changes in cognitive functioning in daily life. At each burst, participants performed cognitive assessment five times a day for 14 days. 138 adults (Mage=49.4) who completed all three bursts were included in this study. Growth curve modeling showed that, on average, scores of cognitive functioning were improved across a 2 year period (p<.001). The chronic lonely group (in the highest tertile at all 3 bursts) showed less improvement in scores compared to non-lonely people (p<.01), although there was no difference in cognitive functioning at the baseline between two groups. This study indicates that we need a repeated measurement of cognitive functioning and longitudinal approach to detect the effect of chronic loneliness on the rate of cognitive change. Part of a symposium sponsored by the Measurement, Statistics, and Research Design Interest Group.

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Chang, Yaw-Jen, Shia-Chung Chen et Cheng-Li Hsu. « Study on Microchannel Design and Burst Frequency Detection for Centrifugal Microfluidic System ». Advances in Materials Science and Engineering 2013 (2013) : 1–9. http://dx.doi.org/10.1155/2013/137347.

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A centrifugal microfluidic system has been developed in this study, enabling the control and measurement of the burst frequency in order to manipulate the liquid. The radial microfluid chips with different microchannel dimensions were designed for simulation analyses and experimental verifications. The microfluidic flow in the microchannel was analyzed using software CFDRC, providing an accurate result compared with that from experiment. The results show that the design of the overflow microchannel can correctly keep the liquid volume with error as low as 5%. For mercurochrome, the burst frequency has an inverse proportion to the channel width, and the simulation results agree with the experimental results. For oil, however, the experimental and simulation results indicate that the relationship between the burst frequency and channel width is not obvious due to oil properties. Since the simulation approach can provide an accurate prediction of flow behavior in the microchannel, the design of radial microfluid chip and the control of burst frequency can be achieved effectively. A practical application to design the centrifugal microfluidic disc for blood typing test was also carried out in this study. The centrifugal microfluidic system can successfully control the spinning speed to achieve the result of adding reagents in a specific sequence.

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Zha, Bing Ting, He Zhang et Xiang Jin Zhang. « System for Measuring the Burst Point Time Base on APD ». Advanced Materials Research 860-863 (décembre 2013) : 2838–41. http://dx.doi.org/10.4028/www.scientific.net/amr.860-863.2838.

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Aiming at the burst point time measuring device cannot timely show the burst point time measurement situation, a new measuring system was designed. The pulse signal when the ammo was outing of the muzzle and exploding was detected by APD, the light pulse was converted to voltage pulse through an amplifying circuit. The timing display module was designed, the timing circuit got the voltage pulse and timing, and then the burst point time would show on LCD. All the photoelectric detector module was fixed with the special mechanical properties. The system could increase the maximum detection distance effectively, improve its detecting precision, and display the burst point time immediately. With the simulation experiment, the system had no failing to get the burst point time, and owned a stable performance. This design can provide a reference for the optimization and improvement of the burst point time measuring device.

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Holtzer, Roee, Frederick Foley, Vanessa D’Orio, Jessica Spat, Melissa Shuman et Cuiling Wang. « Learning and cognitive fatigue trajectories in multiple sclerosis defined using a burst measurement design ». Multiple Sclerosis Journal 19, n^o 11 (25 février 2013) : 1518–25. http://dx.doi.org/10.1177/1352458513477922.

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Background: Compromised learning and cognitive fatigue are critical clinical features in multiple sclerosis. Objectives: This study was designed to determine the effect of repeated exposures within and across study visits on performance measures of learning and cognitive fatigue in relapsing–remitting multiple sclerosis (RRMS). Methods: Thirty patients with RRMS and 30 controls were recruited. Using a burst measurement design (i.e. repeated assessments within and across study visits) the oral version of the Symbol Digit Modalities Test (SDMT) was administered three times during the baseline and two consecutive monthly follow-up visits for a total of nine test administrations. Learning was assessed within and across study visits whereas cognitive fatigue was assessed during the course of each test administration that was divided into three 30-second intervals. Results: Linear mixed-effect models revealed compromised learning within (95% CI: 2.6355 to 3.9867) and across (95% CI: 1.3250 to 3.1861) visits and worse cognitive fatigue (95% CI: −2.1761 to −0.1720) in patients with RRMS compared with controls. Among patients with RRMS, worse self-rated cognitive dysfunction predicted poor learning within (95% CI: −0.1112 to −0.0020) and across (95% CI: −0.0724 to −0.0106) visits. Conclusions: Burst design is optimal to study learning and cognitive fatigue. This methodology, using the SDMT or other time-efficient tests as outcome measures, can be successfully implemented in longitudinal studies and clinical trials.

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Patrick, Megan E., Jennifer L. Maggs et Eva S. Lefkowitz. « Daily Associations Between Drinking and Sex Among College Students : A Longitudinal Measurement Burst Design ». Journal of Research on Adolescence 25, n^o 2 (4 avril 2014) : 377–86. http://dx.doi.org/10.1111/jora.12135.

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Griffin, Jamie, et Megan E. Patrick. « Understanding Participation in a Web-Based Measurement Burst Design : Response Metrics and Predictors of Participation ». Survey Practice 8, n^o 3 (1 juin 2015) : 1–11. http://dx.doi.org/10.29115/sp-2015-0011.

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Elavsky, Steriani, Jana Blahošová, Michaela Lebedíková, Michał Tkaczyk, Martin Tancos, Jaromír Plhák, Ondřej Sotolář et David Smahel. « Researching the Links Between Smartphone Behavior and Adolescent Well-being With the FUTURE-WP4 (Modeling the Future : Understanding the Impact of Technology on Adolescent’s Well-being Work Package 4) Project : Protocol for an Ecological Momentary Assessment Study ». JMIR Research Protocols 11, n^o 3 (8 mars 2022) : e35984. http://dx.doi.org/10.2196/35984.

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Background Smartphone ownership has increased among teens within the last decade, with up to 89% of adolescents owning a smartphone and engaging daily with the online world through it. Although the results of recent meta-analyses suggest that engaging digital technology plays only a small role in adolescent well-being, parents, professionals, and policymakers remain concerned about the impact that the instant connectivity of smartphones has on adolescent well-being. Objective Herein, we introduce the protocol of a research study investigating the associations between adolescent smartphone use and different facets of well-being (social, physical, and psychological), with the aim to apply innovative methods to address the limitations of existing empirical studies. Methods This 12-month prospective study of adolescents uses a repeated measurement-burst design with the ecological momentary assessment methodology. Adolescents (N=203; age range 13-17 years) complete baseline assessments through online questionnaires, four 14-day intensive data collection bursts, and an online questionnaire at the end of the study. As part of the 4 measurement bursts, adolescent smartphone behavior is assessed objectively by passive data collection of smartphone data logs and through self-reports in short questionnaires administered via a custom-built Android app. Results The protocol describes the study objectives, research tools (including the development of the Android app and specialized software), and process (including pilot studies, the main study, and targets for machine learning approaches). Two of the 203 enrolled participants provided no data during the first data collection burst of the main study. Preliminary analyses of the data from the first data collection burst indicated an acceptable level of compliance (72.25%) with the daily questionnaires. The design of the study will allow for the assessment of both within- and between-person variabilities in smartphone behavior, as well as short-term variation and long-term change in smartphone behavior and how it impacts the indicators of social, physical, and psychological well-being. Conclusions The innovative methods applied in this study (objective smartphone logs, ecological momentary assessment, and machine learning) will allow for a more nuanced assessment of the links between smartphone use and well-being, informing strategies to help adolescents navigate the online world more constructively in terms of the development of their physical, social, and psychological well-being. International Registered Report Identifier (IRRID) DERR1-10.2196/35984

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Duy, Nguyen Ngoc, et Le Hong Khiem. « Feasibility Study of Direct Measurement of Stellar Reaction ²²Mg(α,p)²⁵Al ». Communications in Physics 21, n^o 2 (30 juin 2011) : 169. http://dx.doi.org/10.15625/0868-3166/21/2/114.

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The stellar reaction 22Mg(α,p)25Al plays an important role for understanding the nucleosynthesis of stars. It has never investigated yet. We are planning to study this reaction in environment of X-rays burst with temperature T9 = 1÷3 GK using invert kinematics and thick target method. This paper shows a design for direct investigation of this reaction by simulation method. This design is necessary for experimental setup and for confirmation of the feasibility of the experiment.

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Zeinalov, Shakir, Olga Sidorova, Pavel Sedyshev, Valery Shvetsov, Youngseok Lee et Uk-Won Nam. « Thermal neutron intensity measurement with fission chamber in current, pulse and Campbell modes ». EPJ Web of Conferences 231 (2020) : 05009. http://dx.doi.org/10.1051/epjconf/202023105009.

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In thermal nuclear reactors, most of the power is generated by thermal neutron induced fission. Therefore, fission chambers with targets that respond directly to slow neutrons are of great interest for thermal neutron flux measurements due to relatively low sensitivity to gamma radiation. However, the extreme conditions associated with experiments at very low cross section demand highly possible thermal neutron flux, leading often to substantial design changes. In this paper we report design of a fission chamber for wide range (from 10 to 1012 n/cm2 sec) measurement of thermal neutron flux. Test experiments were performed at the first beam of IBR2 pulsed reactor using digital pulse processing (DPP) technique with modern waveform digitizers (WFD). The neutron pulses detected by the fission chamber in each burst (5 Hz repetition rate) of the reactor were digitized and recorded to PC memory for further on-line and off-line analysis. New method is suggested to make link between the pulse counting, the current mode and the Campbell technique.

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Pfund, Gabrielle, Mathias Allemand et Matthias Hofer. « Daily Social Interactions as a Route to Purposeful Days in Older Adulthood ». Innovation in Aging 5, Supplement_1 (1 décembre 2021) : 212–13. http://dx.doi.org/10.1093/geroni/igab046.820.

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Abstract Sense of purpose predicts slower cognitive decline, reduced risk for health issues, and greater longevity (Pfund & Lewis, 2020). However, work is limited regarding how we can help older adults maintain purposefulness in daily life. The current study explored positive daily social interactions as a route to daily purposefulness in older adults, using a measurement burst design. Older adults completed surveys for five-day bursts spread six months apart (Mean age = 70.75, SD = 7.23; n = 104). Multilevel models demonstrated that on days when individuals reported more positive social interactions, they reported feeling more purposeful (b = 0.39, 95% CI [0.28, 0.51]) when accounting for health, employment, and relationship status. Employment status moderated this association, as daily social interactions were more strongly associated with daily purpose for unemployed/retired individuals (b = -0.23, 95% CI [-0.38, -0.08]). Positive social interactions thus may help older adults maintain purposefulness, particularly after retirement.

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Hakun, Jonathan G., Nelson A. Roque, Courtney R. Gerver et Eric S. Cerino. « Ultra-brief Assessment of Working Memory Capacity : Ambulatory Assessment Study Using Smartphones ». JMIR Formative Research 7 (27 janvier 2023) : e40188. http://dx.doi.org/10.2196/40188.

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Background The development of mobile technology with substantial computing power (ie, smartphones) has enabled the adaptation of performance-based cognitive assessments to remote administration and novel intensive longitudinal study designs (eg, measurement burst designs). Although an “ambulatory” cognitive assessment paradigm may provide new research opportunities, the adaptation of conventional measures to a mobile format conducive to intensive repeated measurement involves balancing measurement precision, administration time, and procedural consistency. Objective Across 3 studies, we adapted “complex span” tests of working memory capacity (WMC) for ultra-brief, smartphone-based administration and examined their reliability, sufficiency, and associations with full-length, laboratory-based computerized administrations. Methods In a laboratory-based setting, study 1 examined associations between ultra-brief smartphone adaptations of the operation span, symmetry span, and rotation span tasks and full-length computerized versions. In study 2, we conducted a 4-day ecological momentary assessment (EMA) study (4 assessments per day), where we examined the reliability of ultra-brief, ambulatory administrations of each task. In study 3, we conducted a 7-day EMA study (5 assessments per day) involving the ultra-brief rotation span task, where we examined reliability in the absence of extensive onboarding and training. Results Measurement models in study 1 suggest that comparable estimates of latent WMC can be recovered from ultra-brief complex span task performance on smartphones. Significant correlations between the ultra-brief tasks and respective full-length versions were observed in study 1 and 2, ranging from r=0.4 to r=0.57. Results of study 2 and study 3 suggest that reliable between-person estimates of operation span, symmetry span, rotation span, and latent WMC can be obtained in 2-3 ultra-brief administrations (equivalent to <1 day of testing in an EMA study design). The results of study 3 replicated our findings, showing that reliable between-person estimates of rotation span may be obtained in as few as 2 ultra-brief administrations in the absence of extensive onboarding and training. In addition, the modification of task parameterization for study 3 improved the estimates of reliability of within-person change. Conclusions Ultra-brief administration of complex span tasks on smartphones in a measurement burst design can generate highly reliable cross-sectional estimates of WMC. Considerations for future mobile cognitive assessment designs and parameterizations are discussed.

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Vallabhapurapu, Hyma Harish, et V. V. Srinivasu. « Galactic Distance Measurement System Design Using a High- $T_c$ Josephson Junction Array for RF Burst Detection in Space ». IEEE Transactions on Applied Superconductivity 25, n^o 5 (octobre 2015) : 1–4. http://dx.doi.org/10.1109/tasc.2015.2470688.

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Dubberke, Frithjof H., Elmar Baumhögger et Jadran Vrabec. « Burst design and signal processing for the speed of sound measurement of fluids with the pulse-echo technique ». Review of Scientific Instruments 86, n^o 5 (mai 2015) : 054903. http://dx.doi.org/10.1063/1.4921478.

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Tamburri, Nicholas, Cynthia McDowell et Stuart MacDonald. « DISSOCIATING RETEST EFFECTS FROM DEVELOPMENTAL CHANGE FOR PREDICTING COGNITIVE STATUS ». Innovation in Aging 6, Supplement_1 (1 novembre 2022) : 652–53. http://dx.doi.org/10.1093/geroni/igac059.2410.

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Abstract In longitudinal designs, unadjusted retest effects can confound developmental change estimates. This study utilized a measurement burst design and three-level multilevel modeling to a) independently parameterize short-term retest and long-term developmental change and b) employ these estimates as predictors of cognitive status at long-term follow-ups. Using data from Project MIND , participants (N=304; aged 64-92 years) were assessed across biweekly sessions nested within annual bursts (spanning up to 17 total assessments over four years). Cognitive impairment no dementia (CIND) status was classified at Years 4 (the final burst assessment) and 8 (the study end date). Response time inconsistencies (RTI) were computed to index intraindividual variability across RT trials of a one-back response time (BRT) task. Three-level multilevel models simultaneously yet independently estimated BRT RTI change across weeks and years, indexing short-term retest and long-term developmental change, respectively. Individual slope estimates were extracted and utilized in multinomial logistic regression models contrasting short- vs. long-term RTI change as predictors of long-term cognitive status. Results from the three-level models indicated that retest and developmental slopes yielded non-redundant sources of variance, providing unique estimates of change that would otherwise be confounded. Further, short- and long-term RTI differentially predicted cognitive status at Years 4 and 8; failing to benefit from retest effects on the BRT task was associated with increased likelihood of cognitive impairment. This innovative approach to parameterizing retest effects can reduce systematic bias in estimates of long-term developmental change, as well as highlight the utility of retest effects as predictors of cognitive health.

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Liu, Shuang, Genjian Qin, Jinsong Li, Binglong Chen, Bang Liu et Dong Li. « Overall Design of Fine Guidance Sensor in Attitude Determination for the SVOM Satellite ». Journal of Physics : Conference Series 2220, n^o 1 (1 mars 2022) : 012010. http://dx.doi.org/10.1088/1742-6596/2220/1/012010.

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Abstract SVOM is a Sino-French cooperation project aiming at Gamma Ray Burst observation. From the top level requirement, during the observation period, the satellite platform should provide a stability of better than 1.6 arcsec/100s. Based on this severe requirement, a high precision attitude measurement device is strongly demanded. This article describes the overall design of a novel optical sensor, called Fine Guidance Sensor, for the SVOM Satellite. First, the functional and performance requirements are presented, including the extremely high measuring precision of 0.3 arcsec in y/z-axis. Second, FGS composition, including hardware and software, and processing flow design are described. Then, working mode switching logic is introduced. Next, attitude determination method and simulation result are shown. The conclusion is obtained and all the required indexes are fulfilled by current FGS design.

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Sharma, Mithun, Sanjeev P. Sahni et Shilpi Sharma. « Validating a destructive measurement system using Gauge R&R — a case study ». Engineering Management in Production and Services 11, n^o 4 (18 décembre 2019) : 34–42. http://dx.doi.org/10.2478/emj-2019-0031.

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Abstract The research study aims to evaluate the precision of the measurement system using Gauge R&R. An experimental research design adopting a positivist empirical approach with deductive strategy was followed to assess the effectiveness of Crossed Gauge R&R technique for validating a measurement system using destructive testing. Crossed Gauge R&R technique in Minitab was found to be highly effective in quantifying different components of measurement variation relative to process variation. Clue generation from the Crossed Gauge R&R study combined with manufacturing and measurement process know-how helped in identifying and eliminating the root causes for measurement variation. Overall Crossed Gauge R&R proved successful in validating the burst strength test equipment. However, it should be noted that manufacturing and test equipment played an equally important part in developing and executing the gauge R&R study and accurately analysing the results. So, Crossed Gauge R&R should be used as an aid rather than the solution for measurement system validation.

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Farhangian, Farzan, et René Landry. « Multi-Constellation Software-Defined Receiver for Doppler Positioning with LEO Satellites ». Sensors 20, n^o 20 (16 octobre 2020) : 5866. http://dx.doi.org/10.3390/s20205866.

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A Multi-Constellation Software-Defined Receiver (MC-SDR) is designed and implemented to extract the Doppler measurements of Low Earth Orbit (LEO) satellite’s downlink signals, such as Orbcomm, Iridium-Next, Globalstar, Starlink, OneWeb, SpaceX, etc. The Doppler positioning methods, as one of the main localization algorithms, need a highly accurate receiver design to track the Doppler as a measurement for Extended Kalman Filter (EKF)-based positioning. In this paper, the designed receiver has been used to acquire and track the Doppler shifts of two different kinds of LEO constellations. The extracted Doppler shifts of one Iridium-Next satellite as a burst-based simplex downlink signal and two Orbcomm satellites as continuous signals are considered. Also, with having the Two-Line Element (TLE) for each satellite, the position, and orbital elements of each satellite are known. Finally, the accuracy of the designed receiver is validated using an EKF-based stationary positioning algorithm with an adaptive measurement matrix. Satellite detection and Doppler tracking results are analyzed for each satellite. The positioning results for a stationary receiver showed an accuracy of about 132 m, which means 72% accuracy advancements compared to single constellation positioning.

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Linden-Carmichael, Ashley N., Brian H. Calhoun, Megan E. Patrick et Jennifer L. Maggs. « Are protective behavioral strategies associated with fewer negative consequences on high-intensity drinking days ? Results from a measurement-burst design. » Psychology of Addictive Behaviors 32, n^o 8 (décembre 2018) : 904–13. http://dx.doi.org/10.1037/adb0000421.

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Wang, M., Z. Bian, Y. Wang, D. Li, X. Li, J. Cai, P. Wang et al. « A 64-channel high-time resolution digital waveform sampling electronic system based on DRS4 for positron burst annihilation lifetime measurement ». Journal of Instrumentation 17, n^o 10 (1 octobre 2022) : T10001. http://dx.doi.org/10.1088/1748-0221/17/10/t10001.

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Abstract Measurements of the positron burst annihilation lifetime place high demand on the time discrimination of electronics. DRS4 chips based on switched capacitor array technology (SCA) are used to develop an electronic system with a total (2048 + 256)-channel sampling rate up to 5.12 GSPS, which can provide better time resolution and flexible data processing. The electronic system is modular in design and includes a front-end waveform sampling module (WSM) with 32 waveform sampling boards, each with 64 input channels plus 8 additional channels(one per DRS4 chip) for time calibaion, in addition to a back-end data processing module (DPM). The fan-out circuit integrated with the DPM will fan out the T0 signal in multiple stages at the time of positron burst generation and provide a common starting time and trigger signal for every DRS4 chip in the WSM. In this electronic system, the jitter of T0 after three-stage fan-out is 18 ps. After DC offset correction and time interval nonuniformity calibration, the coincidence time resolution with other channels is about 21 ps (σ). In addition, we correct the time difference of different channels of different chips, which is caused by different trace lengths of the multi-level fan-out T0 signal and the different fabrication processes. The electronic system is used to evaluate a 64-pixel detector module, and the time resolution of the detection module is measured to be 44 ps (σ).

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Röcke, Christina, Christiane A. Hoppmann et Petra L. Klumb. « Correspondence Between Retrospective and Momentary Ratings of Positive and Negative Affect in Old Age : Findings From a One-Year Measurement Burst Design ». Journals of Gerontology : Series B 66B, n^o 4 (28 mars 2011) : 411–15. http://dx.doi.org/10.1093/geronb/gbr024.

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Wang, Qian, Ziying Mo, Benle Yin, Lianming Zhang et Pingping Dong. « Bounding the Upper Delays of the Tactile Internet Using Deterministic Network Calculus ». Electronics 12, n^o 1 (21 décembre 2022) : 21. http://dx.doi.org/10.3390/electronics12010021.

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With the increasing popularity of time-sensitive network applications and the gradual integration of the Tactile Internet into people’s lives, how to ensure ultra-low latency has become a demand and challenge for network performance. Therefore, it is extremely important to analyze the performance of the Tactile Internet. In this paper, we propose an analytical model based on deterministic network calculus (DNC) to quantitatively derive the end-to-end performance bounds of the Tactile Internet, develop a tandem model describing the communication of the Tactile Internet network, and analyze delay-related traffic parameters, such as arrival rate and burst size. We investigate the variation of the accuracy of the DNC analytical model and the measurement model under different parameters, and verify the accuracy of the proposed DNC analytical model by theoretical derivation and analysis and comparison with the measurement model under the NS3 platform. We discuss the impact of relevant parameters on the delay boundaries to determine which network configuration enables the end-to-end delay to meet the established requirements. This will provide valuable guidance for the design of Tactile Internet architectures.

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Salthouse, Timothy A. « Robust Cognitive Change ». Journal of the International Neuropsychological Society 18, n^o 4 (18 mai 2012) : 749–56. http://dx.doi.org/10.1017/s1355617712000380.

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AbstractTwo major challenges facing researchers interested in cognitive change are that measures of change are often not very reliable, and they may reflect effects of prior test experience in addition to the factors of primary interest. One approach to dealing with these problems is to obtain multiple measures of change on parallel versions of the same tests in a measurement burst design. A total of 783 adults performed three parallel versions of cognitive tests on two occasions separated by an average of 2.6 years. Performance increased substantially across the three sessions within each occasion, and for all but vocabulary ability these within-occasion improvements were considerably larger than the between-occasion changes. Reliabilities of the changes in composite scores were low, but averages of the three changes had larger, albeit still quite modest, reliabilities. In some cognitive abilities individual differences were evident in the relation of prior test experience and the magnitude of longitudinal change. Although multiple assessments are more time consuming than traditional measurement procedures, the resulting estimates of change are more robust than those from conventional methods, and also allow the influence of practice on change to be systematically investigated. (JINS, 2012, 18, 1–8)

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Gerlach, Martin Enno, Maximilian Zajonc et Bernd Ponick. « Mechanical stress and deformation in the rotors of a high-speed PMSM and IM ». e & ; i Elektrotechnik und Informationstechnik 138, n^o 2 (2 mars 2021) : 96–109. http://dx.doi.org/10.1007/s00502-021-00866-5.

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AbstractHigh-speed electric machines are gaining importance in the field of traction drives and aviation due to their high power density. The evaluation of the mechanical stress in the rotor is one crucial part in the design process for this type of machines. The mechanical stress cannot be measured directly. Accordingly, a validation of the calculated mechanical stress is difficult and normally not performed. Instead of the mechanical stress, the deformation at the rotor surface can be measured using a spin test machine with distance sensors. The deformation can then be used to validate the calculation results.In this paper, the mechanical load exerted on an IM rotor for a $60\,\text{kW}/20000\,\frac{1}{\text{min}}$ 60 kW / 20000 1 min high-speed electric machine and an PMSM rotor for a $75~\text{kW}/25000\,\frac{1}{\text{min}}$ 75 kW / 25000 1 min high-speed electric machine is analysed in detail. The mechanical stress and the deformation are calculated and analysed using a FEM simulation model. Then, a spin test is performed on the two rotors. First, the burst speed is determined by operating two rotor samples above their defined test speed. Then, the deformation is measured at the rotor surface for different operating speeds and the defined test speed. The measurement and the simulation results are compared and discussed.It can be shown that the two designs do not exceed the maximum mechanical stress for the defined operating range. In the deformation measurement of the IM rotor, a plastic deformation up to $\varepsilon _{\text{IM, pl}} = 8$ ε IM, pl = 8 μm and elastic deformation up to $\varepsilon _{\text{IM, el}}=22$ ε IM, el = 22 μm can be seen. In regards to plastics, PMSM rotor expands up to $\varepsilon _{\text{PMSM, pl}}= 5$ ε PMSM, pl = 5 μm. The maximum elastic deformation of the PMSM rotor is $\varepsilon _{\text{PMSM, el}}=40$ ε PMSM, el = 40 μm. The comparison of the calculated and the measured elastic deformation shows good accordance for the two rotor types. Both models are capable of describing the deformation and the state of stress in the rotors. In burst tests, both rotors withstand rotational speeds far above the defined test speed.

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Houben, Marlies, et Peter Kuppens. « Emotion Dynamics and the Association With Depressive Features and Borderline Personality Disorder Traits : Unique, Specific, and Prospective Relationships ». Clinical Psychological Science 8, n^o 2 (25 novembre 2019) : 226–39. http://dx.doi.org/10.1177/2167702619871962.

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Patterns of emotional change in daily life have been consistently linked to depressive and borderline personality disorder (BPD) features. However, dynamic measures and average affect show considerable statistical overlap, and depressive and BPD features are comorbid. Moreover, the prospective nature of these relationships is unclear. We used a measurement burst design in which 202 young adults with varying levels of psychopathological features participated in a week-long experience sampling at baseline and 1-year follow-up. Taking overlap into account, we found that BPD traits were uniquely and specifically linked to higher levels of variability in negative affect (NA). For depressive features, indications were found for a specific association with inertia of NA, but these results were not robust and consistent. In fact, overall, incremental predictive power of the dynamic measures above mean affect was limited, especially for depressive features. Prospective relationships showed that psychopathological features predicted stronger emotion dynamic patterns 1 year later rather than the other way around.

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Silva, Bárbara Cristiane Sordi, Lilian Cássia Bórnia Jacob-Corteletti, Tyuana Sandim da Silveira Sassi, Juliana Nogueira Chaves, Eliene Silva Araújo et Kátia de Freitas Alvarenga. « Contralateral Masking in the Measurement of Auditory Brainstem Responses with Air-Conducted Tone Burst Stimuli in Individuals with Unilateral Hearing Loss ». Journal of the American Academy of Audiology 32, n^o 04 (avril 2021) : 254–60. http://dx.doi.org/10.1055/s-0041-1722985.

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Abstract Background Contralateral noise masking is an important aspect of auditory brainstem response (ABR) measurements. Purpose The primary aim of this study is to determine how contralateral white noise (WN) masking influences the amplitude and the latency of V wave generated during ABR measurements, using tone burst (TB), in adult ears with normal hearing (NH). The secondary aim of this study is to ascertain the need of contralateral masking in ABR measurements with the TB stimuli using a 3A insertion earphone, and to propose the applicability of WN masking in unilateral sensorineural hearing loss (USNHL). Research Design It is a cross-sectional observational and descriptive study. Study Sample Experiment 1: Thirty individuals, without any otologic, psychological, or neurological dysfunction, were selected. Experiment 2: Fifteen individuals with previous audiological diagnoses of severe and profound USNHL were considered. Intervention The study involves ABR TB at specific frequencies of 0.5, 1, 2, and 4 kHz. Data Collection and Analysis Experiment 1: The evaluation was performed at the fixed intensity of 80 dB nHL (decibel normalized hearing level) on the tested ear, followed by the application of simultaneous masking to the nontested ear, intensity ranged from 0 to 80 dB. Experiment 2: ABR threshold measurements were first performed on the ear with hearing loss (HL) at the frequencies of 1, 2, and 4 kHz. The results were subsequently confirmed using contralateral masking. Results Experiment 1: At any given frequency, there were no statistically significant differences in the amplitude and latency of V wave with increase in the intensities of WN masking. Experiment 2: Cross-hearing was observed at least once in all frequencies analyzed through the occurrence of V wave. Conclusion In conclusion, the contralateral WN masking at the maximum intensity of 80 dB does not affect the amplitude and latency of V wave of the ABR TB at 1, 2, and 4 kHz. Contralateral masking for the ABR TB presented using 3A insertion earphones is necessary at 1, 2, and 4 kHz in individuals with severe or profound degrees of USNHL and at intensities of 15, 20, and 10 dB above the ABR threshold of the nontested ear.

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Layland, Eric K., Brian H. Calhoun, Michael A. Russell et Jennifer L. Maggs. « Is Alcohol and Other Substance Use Reduced When College Students Attend Alcohol-Free Programs ? Evidence from a Measurement Burst Design Before and After Legal Drinking Age ». Prevention Science 20, n^o 3 (8 mars 2018) : 342–52. http://dx.doi.org/10.1007/s11121-018-0877-6.

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YUAN, SHOUCAI, et YAMEI LIU. « DUAL THRESHOLD VOLTAGE DOMINO ADDER DESIGN WITH PASS TRANSISTOR LOGIC USING STANDBY SWITCH FOR REDUCING SUB-THRESHOLD LEAKAGE CURRENT ». Journal of Circuits, Systems and Computers 23, n^o 03 (mars 2014) : 1450043. http://dx.doi.org/10.1142/s0218126614500431.

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Standby switch can strongly turn off all the high threshold voltage transistors, which enhances the effectiveness of a dual threshold voltage CMOS technology to reduce sub-threshold leakage current. Sub-threshold leakage currents are especially important in burst mode type integrated circuits where the system is in an idle mode in the majority of the time. The standby switch allows a domino system to enter and leave a low leakage standby mode within a single clock cycle. In addition, we combine domino dynamic logic with pass transistor XNOR and pass transistor NAND gates to achieve logic 1 output during its precharge phase without affecting circuits operation in its evaluation and standby phase. The required process for dual threshold voltage circuit configuration involves only one additional ion implant step to provide an extra threshold voltage. SPICE simulation for our proposed circuits is made using a 0.18 μm CMOS processes from TSMC, with 10 fF capacitive loads in all output nodes, and parameters for typical process corner at 25°C. Layout is designed, wafer is fabricate and measured. The measurement results of fabricated chips are listed and verify that our designed 8-bit carry look-ahead adders (CLAs) reduced power consumption and propagation delay time by more than 15% and around 20%, respectively, when compared with the prior work.

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Buhr, Lilly, Tomasz Moschko, Anne Eppinger Ruiz de Zarate, Ulrike Schwarz, Jan Kühnhausen et Caterina Gawrilow. « The Association of Self-Reported ADHD Symptoms and Sleep in Daily Life of a General Population Sample of School Children : An Inter- and Intraindividual Perspective ». Brain Sciences 12, n^o 4 (25 mars 2022) : 440. http://dx.doi.org/10.3390/brainsci12040440.

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Sleep and Attention-Deficit/Hyperactivity Disorder (ADHD) have repeatedly been found to be associated with each other. However, the ecological validity of daily life studies to examine the effect of sleep on ADHD symptoms is rarely made use of. In an ambulatory assessment study with measurement burst design, consisting of three bursts (each 6 months apart) of 18 days each, 70 German schoolchildren aged 10–12 years reported on their sleep quality each morning and on their subjective ADHD symptom levels as well as their sleepiness three times a day. It was hypothesized that nightly sleep quality is negatively associated with ADHD symptoms on the inter- as well as the intraindividual level. Thus, we expected children who sleep better to report higher attention and self-regulation. Additionally, sleepiness during the day was hypothesized to be positively associated with ADHD symptoms on both levels, meaning that when children are sleepier, they experience more ADHD symptoms. No association of sleep quality and ADHD symptoms between or within participants was found in multilevel analyses; also, no connection was found between ADHD symptoms and daytime sleepiness on the interindividual level. Unexpectedly, a negative association was found on the intraindividual level for ADHD symptoms and daytime sleepiness, indicating that in moments when children are sleepier during the day, they experience less ADHD symptoms. Explorative analyses showed differential links of nightly sleep quality and daytime sleepiness, with the core symptoms of inattention and hyperactivity/impulsivity, respectively. Therefore, future analyses should take the factor structure of ADHD symptoms into account.

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Roche, Remi, et Fatma Yalcinkaya. « Incorporation of PVDF Nanofibre Multilayers into Functional Structure for Filtration Applications ». Nanomaterials 8, n^o 10 (29 septembre 2018) : 771. http://dx.doi.org/10.3390/nano8100771.

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Membranes are considered as a promising technology for separation and filtration processes. Here, novel polyvinylidene fluoride (PVDF) nanofibrous multilayer membranes were fabricated by wire-based industrial electrospinning equipment following by a lamination process. The lamination process was optimised under various applied temperature, force of lamination, and lamination time. Air permeability and burst-pressure tests were run to determine the optimum membranes for filtration application. The structures of the prepared membranes were characterised by scanning electron microscopy and pore-size analysis. The hydrophilic properties of the membranes were evaluated using water contact angle measurement, and the mechanical strength of the membranes was analysed. Air and water filtration tests were run to find the possible application of prepared membranes. The air filtration results showed that membranes had high filtration efficiencies: Over 99.00% for PM2.5, and PM0.1. The water filtration results indicated that permeability of the membranes changed from 288 to 3275 L/m2hbar. The successful preparation of such an interesting material may provide a new approach for the design and development of electrospun filter membranes.

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Yang, Ting-Ting, Yuan-Zheng Cheng, Meng Qin, Yong-Hong Wang, Hong-Li Yu, An-Lin Wang et Wei-Fen Zhang. « Thermosensitive Chitosan Hydrogels Containing Polymeric Microspheres for Vaginal Drug Delivery ». BioMed Research International 2017 (2017) : 1–12. http://dx.doi.org/10.1155/2017/3564060.

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Thermosensitive hydrogels have increasingly received considerable attention for local drug delivery based on many advantages. However, burst release of drugs is becoming a critical challenge when the hydrogels are employed. Microspheres- (MS-) loaded thermosensitive hydrogels were thus fabricated to address this limitation. Employing an orthogonal design, the spray-dried operations of tenofovir (TFV)/Bletilla striata polysaccharide (BSP)/chitosan (CTS) MS were optimized according to the drug loading (DL). The physicochemical properties of the optimal MS (MS F) were characterized. Depending on the gelation temperature and gelating time, the optimal CTS-sodium alginate- (SA-) α,β-glycerophosphate (GP) (CTS-SA-GP) hydrogel was obtained. Observed by scanning electron microscope (SEM), TFV/BSP/CTS MS were successfully encapsulated in CTS-SA-GP. In vitro releasing demonstrated that MS F-CTS-SA-GP retained desirable in vitro sustained-release characteristics as a vaginal delivery system. Bioadhesion measurement showed that MS-CTS-SA-GP exhibited the highest mucoadhesive strength. Collectively, MS-CTS-SA-GP holds great promise for topical applications as a sustained-release vaginal drug delivery system.

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Dille, Marilyn F., Roger M. Ellingson, Garnett P. McMillan et Dawn Konrad-Martin. « ABR Obtained from Time-Efficient Train Stimuli for Cisplatin Ototoxicity Monitoring ». Journal of the American Academy of Audiology 24, n^o 09 (octobre 2013) : 769–81. http://dx.doi.org/10.3766/jaaa.24.9.2.

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Background: Nonbehavioral methods for identifying cisplatin ototoxicity are important for testing patients with cancer who become too tired or sick to provide a reliable response. The auditory brainstem response (ABR) is a nonbehavioral test that is sensitive to ototoxicity but can be time consuming to implement over a range of frequencies and/or levels. To address this issue, trains of stimuli were developed that offer reliable ABR testing over a range of tone-burst frequencies and levels at a time savings of 77% relative to tone-burst stimuli presented individually. The clinical accuracy of this new method has yet to be determined on a clinical population. Purpose: This project was designed to determine the test performance of a time-effective ABR methodology aimed at identifying hearing shifts from cisplatin among veterans. A secondary goal was to determine whether improved test performance could be achieved by including our previously developed ototoxicity risk assessment model in the ABR prediction algorithm. Research Design: A set of discriminant functions were derived using logistic regression to model the risk for cisplatin-induced hearing change. Independent variables were one of several ABR metrics alone and combined with an ototoxicity risk assessment model that includes pre-exposure hearing and cisplatin dose. Receiver operating characteristic curve analysis was used to evaluate the test performance of these discriminant functions. Study Sample: Twenty-two male veterans treated with cisplatin for various cancers provided data from a total of 71 monitoring appointments. Data Collection and Analysis: Data were collected prospectively from one ear of each participant as designated below. Hearing shift was determined for frequencies within an octave of each patient's high-frequency hearing limit, tested in 1/6th-octave steps. ABRs were monitored using a set of two intensity trains from the highest two multiple frequency tone-burst center frequencies (up to 11.3 kHz) that yielded a robust response at baseline. Each intensity train was presented at 65–105 dB peSPL in 10 dB steps. Scorable ABRs were generally limited to the highest two intensities; therefore, analyses concern those levels. Results: The ABR measurement failure was high, up to 52% for some frequencies and levels. Furthermore, the ABR was not frequently obtained at levels below 85 dB peSPL, consistent with previous studies that suggest a stimulus level of greater than 80 dB peSPL is required to obtain a reliable response to trained stimuli. Using multivariate metrics that included the dose-ototoxicity model, the most accurate scoring function was change in amplitude at lowest half-octave frequency obtained at 105 dB (change in wave V amplitude at frequency 2/105). However, absence of wave V at a monitor patient visit of the ABR response at levels 105 or 95 dB peSPL was deemed the preferred scoring function, because it had lower measurement failure and was within one standard error of the most accurate function. Conclusions: Because of the large number of responses that could not be measured at baseline, this technique as implemented holds limited value as an ototoxicity-monitoring method.

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Zhang, Yuezheng, Hongguang Ji et Hanhua Xu. « Study on the Law of Rock Anelastic Recovery and the Characteristics of In Situ Stress Field of 2000 m Deep Stratum in Metal Mines of Coastal Area ». Advances in Materials Science and Engineering 2022 (12 avril 2022) : 1–11. http://dx.doi.org/10.1155/2022/2152814.

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In situ stress field in deep strata is dominated by self-weight stress and tectonic stress, which is the dynamic source of a series of mining dynamic disasters such as rock burst, mine earthquake, and collapse. To develop deep resources and build deep engineering construction, the distribution characteristics of the in situ stress field must first be ascertained, so as to provide a basic basis for the engineering surrounding rock support design and disaster risk prevention and control. In this paper, taking the Sanshandao Gold Mine in the coastal area as the engineering background, in the early stage of the construction of the 2000 m deep shaft, the anelastic strain recovery method was used to measure the deep in situ stress field. The laws and characteristics of hysteretic elastic recovery of rock at different depths are obtained through experiments, and the effects of temperature, time, and other factors on strain recovery are revealed. The in situ stress test results are basically consistent with the traditional test methods. This method has low operational complexity and better application effect in deep formations. The research has accumulated test experience and basis for carrying out in situ stress measurement in the range of 2000 m and even deeper.

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Ruiz, John M., Daniel J. Taylor, Bert N. Uchino, Timothy W. Smith, Matthew Allison, Chul Ahn, Jillian J. Johnson et Joshua M. Smyth. « Evaluating the longitudinal risk of social vigilance on atherosclerosis : study protocol for the North Texas Heart Study ». BMJ Open 7, n^o 8 (août 2017) : e017345. http://dx.doi.org/10.1136/bmjopen-2017-017345.

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IntroductionPsychosocial factors are increasingly recognised as important determinants of cardiovascular disease risk. The North Texas Heart Study aims to understand the mechanisms responsible for this association with a focus on social vigilance (ie, scanning the environment for social threats). There is also growing interest in supplementing traditional methods (eg, survey assessment of psychosocial risk paired with cross-sectional and longitudinal health outcomes) with daily or repeated momentary assessment of psychosocial factors. However, there are relatively few longitudinal studies directly comparing these approaches with hard endpoints.Methods and analysisThe North Texas Heart Study proposes a longitudinal measurement burst design to examine psychosocial determinants of subclinical atherosclerosis. A sample of 300 healthy community participants, stratified by age and gender, will complete survey measures, as well as 2 days of ecological momentary assessment at baseline and at a 2-year follow-up. A range of psychosocial and behavioural factors, objective biomarkers, as well as carotid intima-media thickness (cIMT) will be assessed at both time points. Unadjusted and adjusted models will evaluate cross-sectional associations and determinants of change in the cIMT.Ethics and disseminationThe Institutional Review Board at the study coordinating institute (University of North Texas) has approved this study. Positive, negative or inconclusive primary and ancillary findings will be disseminated in scientific journals and conferences.

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Almeida, David, et Daniel Mroczek. « Stress Processes Over 2 Decades : Findings From the National Study of Daily Experiences ». Innovation in Aging 5, Supplement_1 (1 décembre 2021) : 213. http://dx.doi.org/10.1093/geroni/igab046.822.

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Abstract Daily experiences of stress and the associated sequelae of affective and physiological changes represent the multiple dimensions of a complex, time-dependent process of how stressors unfold in daily life. Daily diaries capture these time-sensitive processes as they occur under real world conditions. Longitudinal changes in stress processes can then be tracked using a measurement burst design: daily diaries repeated longitudinally. Using this design, the National Study of Daily Experiences (NSDE) has generated more than 35,000 days of data from a national sample of over 2,500 adults assessed repeatedly across 20 years of adulthood. The NSDE features details of more than 10,000 reports daily stress including exposure, appraisal and affective responses from adults ranging in age from 24 to 95 years. The current symposium leverages this unique and influential dataset to examine age differences and aging-related changes in daily stress processes with four presentations from the NSDE. First, Dr. Robert Stawski will discuss longitudinal change and age-related differences in exposure to multiple types of daily stressors. Next, Dr. Susan Charles will examine age differences and change in a key element of the stress process: negative affect. Third, Dr. Eric Cerino will describe longitudinal change in appraisals of daily stressors focusing on stressor control. Finally, Dr. David Almeida will examine changes in negative affect reactivity to daily stressors across the 20 years of the NSDE. Dr. Dan Mroczek will discuss the picture these presentations provide of how aging and age-differences impact the daily stress process and future directions for understanding these trajectories.

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Wang, Yifan, Kefu Liu, Xiaowei Xiang, Caihui Zhu et Hao Wang. « The impedance analysis of small intestine fusion by pulse source ». Open Life Sciences 15, n^o 1 (3 novembre 2020) : 808–18. http://dx.doi.org/10.1515/biol-2020-0082.

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AbstractThe radiofrequency-induced intestine fusion has been widely studied as an alternative for traditional suture in surgery, but fusion quality cannot be evaluated directly. Impedance measurement can evaluate fusion quality, but the relation between impedance and the fusion quality needs optimization for best results. The present study reports the optimum resistance of small intestine fusion. As the feedback signal, resistance was considered the indicator of the fusion completion for the device design of intestine fusion and an in-depth study of microstructure change. A self-design pulse source was used for the small intestine fusion with adjustable voltage, duty ratio, frequency and output time. A frequency of 440 kHz was set, whereas voltage, output time and compression pressure (CP) of the small intestine were independent variables. Different conditions of voltage, CP and time were investigated for achieving the highest burst pressure (BP) measured with a pressure gauge and a peristaltic pump. Each parameter of the equivalent circuit model was calculated by an experimental waveform. Hematoxylin–eosin staining of fusion samples was used for assessing the quality of fusion. The real-time current was measured and recorded during the fusion for the calculation of capacitance and resistance. The highest BP of 38.9 mmHg was achieved with a CP of 900 kPa, a voltage of 50 V and a time of 5 s. Finally, an optimum extracellular resistance range of 61.0–86.2 Ω was found as the optimum resistance for the end of fusion, thus indicating automatic fusion with the best fusion quality.

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Wang, Hao, Yu Wang, Shuang Zhao, Lan-ping Wang et Hui An. « The transnational comparative study on the potential risks and efficiency of commercial banks based on the weight-limited DEA model ». China Finance Review International 8, n^o 4 (19 novembre 2018) : 441–52. http://dx.doi.org/10.1108/cfri-06-2017-0126.

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Purpose The purpose of this paper is to calculate the bank efficiency of removing potential risks that are hidden from the extreme portfolio of bank’s assets and further compare the differences and causes of bank’s efficiency and potential risk level between China’s representative banks and OECD representative banks in 2011-2015. Design/methodology/approach Based on the weight-limited DEA model, this paper calculates the bank’s efficiency and further compares the differences between China’s representative banks and OECD representative banks by using commercial banks’ transnational data. Findings By analyzing US representative banks’ data, the authors find that the excessive expansion of the scale of banks’ investment for the non-real economy shrinks after the bubble burst and would not improve the efficiency of banks immediately. The OECD representative banks rather prefer to extreme asset portfolio so that the potential risks gradually increase, while there is a diminishing effect on investments in non-real economies to improve bank efficiency. On the other hand, China’s representative banks have the signs of reducing investment in the real estate market, but the existence of the bubble in the market led to a lagged effect on the impact of adjustment of bank asset portfolio on efficiency. Research limitations/implications This paper has practical significance for commercial banks to improve efficiency and reduce credit risks. This is conducive to the implementation of targeted supervision by the banking supervision department. Practical implications Based on the lesson that the financial crisis created by the real estate bubble burst in the USA in 2008 and the financial market active guidance of the developed economies, faced with the reality of Chinese real estate market bubble rising and the continuous improvement of Chinese financial market, this paper compares the differences between representative banks in China and OECD, and explores the causes by using the cross-country data of commercial banks. Originality/value By adjusting the weight of the input variables in the efficiency measurement, quantifying the risk is often overlooked by the changes in bank efficiency. This potential risk is caused by the bank’s investment preferences in the non-real economy represented by real estate and tradable financial assets.

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Sliwinski, Martin J. « Measurement-Burst Designs for Social Health Research ». Social and Personality Psychology Compass 2, n^o 1 (janvier 2008) : 245–61. http://dx.doi.org/10.1111/j.1751-9004.2007.00043.x.

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Notay, Karambir, Anthony V. Incognito et Philip J. Millar. « Acute beetroot juice supplementation on sympathetic nerve activity : a randomized, double-blind, placebo-controlled proof-of-concept study ». American Journal of Physiology-Heart and Circulatory Physiology 313, n^o 1 (1 juillet 2017) : H59—H65. http://dx.doi.org/10.1152/ajpheart.00163.2017.

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Acute dietary nitrate ([Formula: see text]) supplementation reduces resting blood pressure in healthy normotensives. This response has been attributed to increased nitric oxide bioavailability and peripheral vasodilation, although nitric oxide also tonically inhibits central sympathetic outflow. We hypothesized that acute dietary [Formula: see text] supplementation using beetroot (BR) juice would reduce blood pressure and muscle sympathetic nerve activity (MSNA) at rest and during exercise. Fourteen participants (7 men and 7 women, age: 25 ± 10 yr) underwent blood pressure and MSNA measurements before and after (165–180 min) ingestion of 70ml high-[Formula: see text] (~6.4 mmol [Formula: see text]) BR or [Formula: see text]-depleted BR placebo (PL; ~0.0055 mmol [Formula: see text]) in a double-blind, randomized, crossover design. Blood pressure and MSNA were also collected during 2 min of static handgrip (30% maximal voluntary contraction). The changes in resting MSNA burst frequency (−3 ± 5 vs. 3 ± 4 bursts/min, P = 0.001) and burst incidence (−4 ± 7 vs. 4 ± 5 bursts/100 heart beats, P = 0.002) were lower after BR versus PL, whereas systolic blood pressure (−1 ± 5 vs. 2 ± 5 mmHg, P = 0.30) and diastolic blood pressure (4 ± 5 vs. 5 ± 7 mmHg, P = 0.68) as well as spontaneous arterial sympathetic baroreflex sensitivity ( P = 0.95) were not different. During static handgrip, the change in MSNA burst incidence (1 ± 8 vs. 8 ± 9 bursts/100 heart beats, P = 0.04) was lower after BR versus PL, whereas MSNA burst frequency (6 ± 6 vs. 11 ± 10 bursts/min, P = 0.11) as well as systolic blood pressure (11 ± 7 vs. 12 ± 8 mmHg, P = 0.94) and diastolic blood pressure (11 ± 4 vs. 11 ± 4 mmHg, P = 0.60) were not different. Collectively, these data provide proof of principle that acute BR supplementation can decrease central sympathetic outflow at rest and during exercise. Dietary [Formula: see text] supplementation may represent a novel intervention to target exaggerated sympathetic outflow in clinical populations. NEW & NOTEWORTHY The hemodynamic benefits of dietary nitrate supplementation have been attributed to nitric oxide-mediated peripheral vasodilation. Here, we provide proof of concept that acute dietary nitrate supplementation using beetroot juice can decrease muscle sympathetic outflow at rest and during exercise in a normotensive population. These results have applications for targeting central sympathetic overactivation in disease.

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Madonna, Fabio, Rigel Kivi, Jean-Charles Dupont, Bruce Ingleby, Masatomo Fujiwara, Gonzague Romanens, Miguel Hernandez et al. « Use of automatic radiosonde launchers to measure temperature and humidity profiles from the GRUAN perspective ». Atmospheric Measurement Techniques 13, n^o 7 (8 juillet 2020) : 3621–49. http://dx.doi.org/10.5194/amt-13-3621-2020.

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Abstract. In the last two decades, technological progress has not only seen improvements to the quality of atmospheric upper-air observations but also provided the opportunity to design and implement automated systems able to replace measurement procedures typically performed manually. Radiosoundings, which remain one of the primary data sources for weather and climate applications, are still largely performed around the world manually, although increasingly fully automated upper-air observations are used, from urban areas to the remotest locations, which minimize operating costs and challenges in performing radiosounding launches. This analysis presents a first step to demonstrating the reliability of the automatic radiosonde launchers (ARLs) provided by Vaisala, Meteomodem and Meisei. The metadata and datasets collected by a few existing ARLs operated by the Global Climate Observing System (GCOS) Reference Upper-Air Network (GRUAN) certified or candidate sites (Sodankylä, Payerne, Trappes, Potenza) have been investigated and a comparative analysis of the technical performance (i.e. manual versus ARL) is reported. The performance of ARLs is evaluated as being similar or superior to those achieved with the traditional manual launches in terms of percentage of successful launches, balloon burst and ascent speed. For both temperature and relative humidity, the ground-check comparisons showed a negative bias of a few tenths of a degree and % RH, respectively. Two datasets of parallel soundings between manual and ARL-based measurements, using identical sonde models, provided by Sodankylä and Faa'a stations, showed mean differences between the ARL and manual launches smaller than ±0.2 K up to 10 hPa for the temperature profiles. For relative humidity, differences were smaller than 1 % RH for the Sodankylä dataset up to 300 hPa, while they were smaller than 0.7 % RH for Faa'a station. Finally, the observation-minus-background (O–B) mean and root mean square (rms) statistics for German RS92 and RS41 stations, which operate a mix of manual and ARL launch protocols, calculated using the European Centre for Medium-Range Weather Forecasts (ECMWF) forecast model, are very similar, although RS41 shows larger rms(O–B) differences for ARL stations, in particular for temperature and wind. A discussion of the potential next steps proposed by GRUAN community and other parties is provided, with the aim to lay the basis for the elaboration of a strategy to fully demonstrate the value of ARLs and guarantee that the provided products are traceable and suitable for the creation of GRUAN data products.

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Piker, Erin G., Gary P. Jacobson, Devin L. McCaslin et Linda J. Hood. « Normal Characteristics of the Ocular Vestibular Evoked Myogenic Potential ». Journal of the American Academy of Audiology 22, n^o 04 (avril 2011) : 222–30. http://dx.doi.org/10.3766/jaaa.22.4.5.

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Background: Stimulus-evoked electromyographic changes can be recorded from the extraocular muscles. These short-latency negative-polarity evoked myogenic potentials are called ocular vestibular evoked myogenic potentials (oVEMPs). To date there has not yet been a large-scale study examining the effects of age on the amplitude, latency, threshold, and interaural differences of the oVEMP to air-conducted stimuli. Further, before the oVEMP can become a useful clinical tool, the test–retest reliability of the response must be established. The oVEMP response, once more completely understood, may provide diagnostic information that is complementary to the cervical vestibular evoked myogenic potential (cVEMP; i.e., sternocleidomastoid muscle). Purpose: To describe the normal characteristics of oVEMP in a cohort of age-stratified subjects, to assess the test–retest reliability of the oVEMP, and to determine if reference contamination occurs using a common recommended infraorbital reference electrode derivation. Research Design: A prospective, descriptive study design was used for an investigation with a threefold purpose in which oVEMP recordings were made from the extraocular muscles (e.g., inferior oblique muscle). Study Sample: Fifty otologically and neurologically normal adults and children served as subjects. Subjects ranged in age from 8 to 88 yr. Data Collection and Analysis: In Investigation 1, oVEMPs were recorded from the ipsilateral and contralateral inferior oblique muscles for all subjects. The stimulus was a 95 dB nHL 500 Hz tone burst. Next, oVEMP thresholds were obtained. Amplitude, latency, and thresholds were tabulated, and descriptive statistics were used to calculate normative values. Age-related differences in oVEMP component latencies, amplitudes, interaural amplitude asymmetries (IAAs), and thresholds were determined using an analysis of variance. In Investigation 2, oVEMPs were recorded twice in 10 subjects, once (test) and once approximately 10 weeks later (retest). Test–retest reliability for the oVEMP peak-to-peak amplitude, n1 latency, p1 latency, n1 threshold, and IAA were assessed with intraclass correlation coefficients (ICCs) calculated using a two-way random-effects, absolute-agreement model. In Investigation 3, a four-channel oVEMP recording was conducted in 10 subjects. Both observational methods and paired-sample t-tests were used to evaluate the effect that reference electrode location had on the oVEMP. Results: oVEMP responses were present bilaterally in 90% of our subjects. The upper limit of oVEMP amplitude asymmetry, defined as the mean plus two standard deviations, was 34% (mean = 14%, SD 10), and the mean n1 latency was 12.5 (SD 1.0) msec. The amplitude of the response significantly decreased and the threshold significantly increased with increasing age, with the greatest age effects occurring in subjects 50 yr and older. Test–retest reliability was acceptable (ICCs for the measurement variables ranged from .53 to .87). Using conventional recommended recording techniques, evidence of reference contamination occurred for all subjects, resulting in a mean amplitude reduction of 30% (range = 18%–43%). Conclusions: Age results in systematic changes in oVEMP measurement parameters. The test–retest reliability is acceptable, and reference contamination averaging 30% is guaranteed using a second infraorbital electrode as the inverting input (i.e., reference electrode) for bipolar recordings. The oVEMP can be used as a complementary diagnostic tool to the cVEMP in evaluating subjects with suspected peripheral vestibular disorders.

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Ulfhake, B., H. Lerat, J. Honetschlager, K. Pernold, M. Rynekrová, K. Escot, C. Recordati et al. « A multicentre study on spontaneous in-cage activity and micro-environmental conditions of IVC housed C57BL/6J mice during consecutive cycles of bi-weekly cage-change ». PLOS ONE 17, n^o 5 (25 mai 2022) : e0267281. http://dx.doi.org/10.1371/journal.pone.0267281.

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Mice respond to a cage change (CC) with altered activity, disrupted sleep and increased anxiety. A bi-weekly cage change is, therefore, preferred over a shorter CC interval and is currently the prevailing routine for Individually ventilated cages (IVCs). However, the build-up of ammonia (NH3) during this period is a potential threat to the animal health and the literature holds conflicting reports leaving this issue unresolved. We have therefor examined longitudinally in-cage activity, animal health and the build-up of ammonia across the cage floor with female and male C57BL/6 mice housed four per IVC changed every other week. We used a multicentre design with a standardised husbandry enabling us to tease-out features that replicated across sites from those that were site-specific. CC induce a marked increase in activity, especially during daytime (~50%) when the animals rest. A reduction in density from four to two mice did not alter this response. This burst was followed by a gradual decrease till the next cage change. Female but not male mice preferred to have the latrine in the front of the cage. Male mice allocate more of the activity to the latrine free part of the cage floor already the day after a CC. A behaviour that progressed through the CC cycle but was not impacted by the type of bedding used. Reducing housing density to two mice abolished this behaviour. Female mice used the entire cage floor the first week while during the second week activity in the latrine area decreased. Measurement of NH3 ppm across the cage floor revealed x3 higher values for the latrine area compared with the opposite area. NH3 ppm increases from 0–1 ppm to reach ≤25 ppm in the latrine free area and 50–100 ppm in the latrine area at the end of a cycle. As expected in-cage bacterial load covaried with in-cage NH3 ppm. Histopathological analysis revealed no changes to the upper airways covarying with recorded NH3 ppm or bacterial load. We conclude that housing of four (or equivalent biomass) C57BL/6J mice for 10 weeks under the described conditions does not cause any overt discomfort to the animals.

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Dietler, Rodolfo, Mathieu Hursin, Gregory Perret, Kelly Jordan et Rakesh Chawla. « A novel design approach for a neutron measurement station for burnt fuel ». Nuclear Instruments and Methods in Physics Research Section A : Accelerators, Spectrometers, Detectors and Associated Equipment 693 (novembre 2012) : 59–66. http://dx.doi.org/10.1016/j.nima.2012.07.009.

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Rush, Jonathan, Emily Willroth, Eileen Graham, Daniel Mroczek et David Almeida. « The Effect of Long-Term Changes in Daily Stress Processes on Prospective Health : An Application of Three-Level SEM ». Innovation in Aging 4, Supplement_1 (1 décembre 2020) : 509–10. http://dx.doi.org/10.1093/geroni/igaa057.1645.

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Abstract The study of change over time, contexts, cohorts, and people is influenced by the sampling of observations within longitudinal studies. Intensive measurement designs, embedded within long-term longitudinal studies, provide new opportunities to understand changes in dynamic processes, as well as determinants and consequences of these changes over time. The present investigation examined whether short-term dynamic associations accounted for individual differences in prospective health functioning. We used measurement burst data from the National Study of Daily Experiences subsample (N = 2485) embedded within the Midlife in the United States longitudinal study. Two measurement bursts were separated by ten years, with each containing daily measures of stress and affect across eight consecutive days. Functional health was measured by basic and instrumental activities of daily living at three measurement waves spanning 20 years. Three-level structural equation models were fit to simultaneously model short-term within-person associations between stress and affect (i.e., stress reactivity) and long-term changes in these associations over the ten year period. Individual differences in long-term changes of the short-term dynamic association predicted both basic and instrumental activities of daily living at 20 year follow-up (estimate = 5.26, SE = 2.54, p < .01; and estimate = 5.48, SE = 2.81, p < .01, respectively). These effects were present after adjusting for mean levels of both stress and affect. We highlight how characterizing individuals based on the strength of their within-person associations across multiple time scales can be informative in predicting distal health outcomes.

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Merchant, Shabbir Hussain I., Eleni Frangos, Jacob Parker, Megan Bradson, Tianxia Wu, Felipe Vial-Undurraga, Giorgio Leodori et al. « The role of the inferior parietal lobule in writer’s cramp ». Brain 143, n^o 6 (18 mai 2020) : 1766–79. http://dx.doi.org/10.1093/brain/awaa138.

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Abstract Humans have a distinguishing ability for fine motor control that is subserved by a highly evolved cortico-motor neuronal network. The acquisition of a particular motor skill involves a long series of practice movements, trial and error, adjustment and refinement. At the cortical level, this acquisition begins in the parieto-temporal sensory regions and is subsequently consolidated and stratified in the premotor-motor cortex. Task-specific dystonia can be viewed as a corruption or loss of motor control confined to a single motor skill. Using a multimodal experimental approach combining neuroimaging and non-invasive brain stimulation, we explored interactions between the principal nodes of the fine motor control network in patients with writer’s cramp and healthy matched controls. Patients and healthy volunteers underwent clinical assessment, diffusion-weighted MRI for tractography, and functional MRI during a finger tapping task. Activation maps from the task-functional MRI scans were used for target selection and neuro-navigation of the transcranial magnetic stimulation. Single- and double-pulse TMS evaluation included measurement of the input-output recruitment curve, cortical silent period, and amplitude of the motor evoked potentials conditioned by cortico-cortical interactions between premotor ventral (PMv)-motor cortex (M1), anterior inferior parietal lobule (aIPL)-M1, and dorsal inferior parietal lobule (dIPL)-M1 before and after inducing a long term depression-like plastic change to dIPL node with continuous theta-burst transcranial magnetic stimulation in a randomized, sham-controlled design. Baseline dIPL-M1 and aIPL-M1 cortico-cortical interactions were facilitatory and inhibitory, respectively, in healthy volunteers, whereas the interactions were converse and significantly different in writer’s cramp. Baseline PMv-M1 interactions were inhibitory and similar between the groups. The dIPL-PMv resting state functional connectivity was increased in patients compared to controls, but no differences in structural connectivity between the nodes were observed. Cortical silent period was significantly prolonged in writer’s cramp. Making a long term depression-like plastic change to dIPL node transformed the aIPL-M1 interaction to inhibitory (similar to healthy volunteers) and cancelled the PMv-M1 inhibition only in the writer’s cramp group. These findings suggest that the parietal multimodal sensory association region could have an aberrant downstream influence on the fine motor control network in writer’s cramp, which could be artificially restored to its normal function.

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Shehata, Ahmed E. M., Siva P. Kambhampati, Jiangxia Wang et Uri S. Soiberman. « Burst Pressures in Eyes with Clear Corneal Incisions Treated with ReSure Glue ». Journal of Ophthalmology 2021 (4 février 2021) : 1–3. http://dx.doi.org/10.1155/2021/6691489.

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Purpose. This study aims to measure burst pressures in 3 mm clear corneal incisions sealed with ReSure, a biodegradable hydrogel sealant, and to compare it to traditional 10-0 nylon sutures and unsealed controls. Design. An ex vivo animal study. Methods. 3 mm clear corneal incisions were performed in rabbit eyes (ex vivo). The burst pressure was determined, and then, the incisions were sealed with either ReSure glue or a single 10-0 nylon suture. Burst pressure measurements were repeated. Results. Fourteen eyes were included. The median burst pressure in the suture-control group (7 eyes) prior to suture application was 7 mmHg (range: 0–45); the median burst pressure in the 7 glue-controls was 36 mmHg (range: 5–61, p = 0.08 for the comparison of the two control groups). The median burst pressure in the glue group was 93 mmHg (range: 39–129, p = 0.043 when compared to glue-control). The median burst pressure in the suture group was 158 mmHg (range: 70–180, p = 0.018 when compared to suture-control). There was no statistically significant difference in burst pressure values between the glue and suture groups ( p = 0.08). Conclusion. In this study, ReSure glue applied to 3 mm clear corneal incisions provided sufficient resistance to elevated intraocular pressure when compared to controls. The results of this study suggest that ReSure glue may be comparable to a single 10-0 nylon suture in resisting fluid egress during the early postoperative period.

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Halápi, Dávid, et László Varga. « Application of Additive Technology in Precision Casting ». International Journal of Engineering and Management Sciences 5, n^o 2 (15 avril 2020) : 43–56. http://dx.doi.org/10.21791/ijems.2020.2.6.

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In this paper the surface of the prepared test specimens had been examined with light microscopy and surface roughness measurements. In order to improve the surface smoothness of PLA specimens, application of ethyl acetate was required. After this surface treatment, microscopic images were taken again. The melting and decomposition temperatures of the materials had been determined using derivatography. The chosen method was precision casting with gypsum molding. Also, the plaster molds had been burnt out according to the predefined melting and firing diagram. The measurement series shows that the samples produced by 3D printing can also be used in the field of precision casting. They provide greater freedom of design, more sophisticated pieces, and prototypes can be finished in a shorter amount of time.

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