Switching Rate Research Articles

High-repetition rate acousto-optic gated SAF-LIBS for quantitative analysis

The self-absorption-free LIBS (SAF-LIBS) we developed recently was demonstrated to be effective in reducing the effects of self-absorption, but it is difficult to be applied to industrial production because of the need for expensive, large size and fragile components such as ICCD and echelle spectrometer. In this study, a novel quantitative analysis technology named as high repetition rate acousto-optic gated SAF-LIBS is proposed, in which AOM acts as the optical gating switch and high-repetition rate laser as the excitation source, so that the miniaturized CCD spectrometer can be used in the SAF-LIBS. Univariate quantitative analysis results show that the linear correlation coefficient of the calibration curve of aluminum is 0.98, and the average absolute error is 0.15%, indicating that the measurement accuracy is almost the same as traditional SAF-LIBS. This work will greatly reduce the cost and size of the system and improve the practicability of SAF-LIBS.

An aggregation model of cockroaches with fast-or-slow motion dichotomy.

We propose a mathematical model, namely a reaction-diffusion system, to describe social behaviour of cockroaches. An essential new aspect in our model is that the dispersion behaviour due to overcrowding effect is taken into account as a counterpart to commonly studied aggregation. This consideration leads to an intriguing new phenomenon which has not been observed in the literature. Namely, due to the competition between aggregation towards areas of higher concentration of pheromone and dispersion avoiding overcrowded areas, the cockroaches aggregate more at the transition area of pheromone. Moreover, we also consider the fast reaction limit where the switching rate between active and inactive subpopulations tends to infinity. By utilising improved duality and energy methods, together with the regularisation of heat operator, we prove that the weak solution of the reaction-diffusion system converges to that of a reaction-cross-diffusion system.

33172 Real-world treatment patterns of adults with psoriasis initiated on apremilast or biologics

Background: Patients with psoriasis (PsO) commonly switch treatments due to adverse events and declining efficacy. This study used real-world data to assess treatment switching, discontinuation, and persistence in biologic- and apremilast-naive patients with PsO. Methods: Optum Clinformatics Data Mart claims were used to identify adults with PsO who newly initiated (index) treatment with apremilast, tumor necrosis factor inhibitors (TNFi; infliximab, adalimumab, etanercept, certolizumab pegol), or interleukin inhibitors (ILi; ustekinumab, guselkumab, tildrakizumab, risankizumab, brodalumab, secukinumab, ixekizumab) between 7/1/2014 and 12/31/2019, and had continuous enrollment for ≥1 year pre-index and ≥2 years post-index. Patients were propensity score matched 1:1:1 to adjust for possible selection bias. Rates of treatment switch, discontinuation, and persistence were measured over 24 months (24 m) of follow-up. Results: 2535 patients were included (845 per cohort). At 24 m, switch rates were highest for TNFi (32%), followed by apremilast (21%) and ILi (14%), with the majority of patients switching to treatment with a different mechanism of action. Overall discontinuation rates at 24m were 59%, 42%, and 58% for apremilast, TNFi, and ILi, respectively. More patients reinitiated ILi after discontinuing (65%) than either apremilast (40%) or TNFi (37%). At 24m, 21%, 25%, and 28% of patients on apremilast, TNFi, and ILi, respectively, persisted with same index treatment. Conclusion: This retrospective study showed that switching PsO treatment is common and increases over time. Oral treatments had lower switch rates compared with TNFi despite lower effectiveness in biologic-naive patients. Discontinuation was higher and persistency was lower for apremilast than for more effective biologic treatments.

Clinical and economic burden of tumor lysis syndrome among patients with chronic lymphocytic leukemia/small lymphocytic lymphoma: A real-world US retrospective study.

BACKGROUND: Tumor lysis syndrome (TLS) is a potentially fatal complication of antineoplastic treatments for hematologic malignancies, including chronic lymphocytic leukemia (CLL)/small lymphocytic lymphoma (SLL). Patients developing TLS require intensive care, adding to the overall clinical and economic burden of CLL/SLL. OBJECTIVE: To analyze TLS-associated health care resource utilization (HCRU) and costs in patients with CLL/SLL treated with regimens associated with a high TLS risk (per treatment guidelines), ie, anti-CD20-based chemoimmunotherapy (CIT), lenalidomide, obinutuzumab, or venetoclax. METHODS: Adult patients with CLL/SLL in the MarketScan Databases (January 1, 2006, to April 30, 2020) initiated on CIT, lenalidomide, obinutuzumab, or venetoclax (index date) on or after January 1, 2007, were included in the analysis. Treatment-emergent TLS was defined as TLS occurring in the first 90 days of active treatment. The post-index period was divided into 30-day intervals until the end of the index regimen; intervals pre-TLS were non-TLS intervals and those starting from the TLS event were TLS intervals. Per-patient-per-month (PPPM) HCRU and costs were compared between TLS and non-TLS intervals using generalized linear models adjusted for baseline and time-varying confounders. The proportion of patients in the TLS cohort (patients with treatment-emergent TLS) and non-TLS cohort (patients with no treatment-emergent TLS) who switched treatment within 90 days post-index was compared using Kaplan-Meier rates with logrank P values. RESULTS: Among 6,343 patients with CLL/SLL, 71 (1.1%) developed treatment-emergent TLS (venetoclax: 11.5%; other regimens: 0.8%) after a mean (median) of 12.7 (7.0) days following treatment initiation (mean [median] duration of index regimen: 16.0 [10.0] months); 12 (0.2%) developed clinical TLS (venetoclax: 3.1%; other regimens: 0.1%). TLS was associated with 1.7 times more inpatient admissions (P < 0.001), 2 times more days of inpatient stay (P = 0.012), 22% fewer days of antineoplastic drug administration (P = 0.020), and $3,062 PPPM higher health care costs (P = 0.016), which were mainly driven by $1,688 PPPM higher inpatient costs (P = 0.044). Higher costs were observed among both patients who initiated venetoclax (TLS: $24,170; non-TLS: $20,091) and those who initiated other regimens (TLS: $8,746; non-TLS: $6,915). More patients in the TLS vs non-TLS cohort switched treatment in the first 90 days of treatment (12.6% vs 5.1%, P = 0.006). CONCLUSIONS: TLS was associated with a substantial cost burden (driven by inpatient costs) and higher rate of treatment switching (vs non-TLS cohort) in patients with CLL/SLL treated with CIT, obinutuzumab, lenalidomide, or venetoclax. The risk of treatment-emergent TLS and associated incremental HCRU and costs, as well as the potential impact on quality of life, should be weighed when evaluating the risk-benefit of therapies in CLL/SLL management. DISCLOSURES: Dr Rogers has received research funding from Genentech, AbbVie, Novartis, and Janssen (not for the present study); consulting fees from Acerta Pharma, AstraZeneca, Innate Pharma, Pharmacyclics, Genentech, and AbbVie; and travel funding from AstraZeneca. Mr Emond, Mr Kinkead, Ms Lafeuille, and Mr Lefebvre are employees of Analysis Group, Inc., which has provided paid consulting services to Janssen Scientific Affairs, LLC. Drs Lu and Huang are employees of Janssen Scientific Affairs, LLC, and stockholders of Johnson & Johnson. Ms Côté-Sergent was an employee of Analysis Group, Inc., at the time the study was conducted. This study was funded by Janssen Scientific Affairs, LLC. The sponsor was involved in the study design; data collection, analysis, and interpretation; manuscript writing; and the decision to publish the article.

Microstrip feed dual band and triple band frequency reconfigurable antenna for diverse applications

A compact reconfigurable antenna which can operate at wide range of frequency bands like ITU-band (7.725 GHz– 8.5 GHz), X-band (8-12.5GHz) and Wi-Fi (3.6 GHz, 5 GHz, and 5.9 GHz) very efficiently with gain ranging from 10dB to 12dB which can be useful for commercial applications is designed. A circular shaped antenna with microstrip line feeding is designed with highest switching rate with the abet of two-diodes which provides state of flexibility in terms of frequency reconfigurability, number of operating bands, frequency reconfigurability and stable radiation pattern with easily fabricating opportunities consists of stub loaded circular patch radiator. The novelty of proposed ultramodern antenna in terms of the band-width frequency reconfigurability, and multiple operating modes are achieved due to the collation performance of the suggested antenna operates in commercial applications.

Keep flexible—Keep switching? Boundary conditions of the influence of forced task switching on voluntary task switching.

Frequent forced switching between tasks has been shown to reduce switch costs and increase voluntary switch rates. So far, however, the boundary conditions of the influence of forced task switching on voluntary task switching are unknown. Thus, the present study was aimed to test different aspects of generalizability (across items, tasks, and time) of switching-induced flexibility established in forced-choice trials on voluntary switching in free-choice trials. To this end, stimuli and tasks were systematically varied between forced- and free-choice trials in a hybrid task-switching paradigm. In a series of three experiments, we manipulated forced-choice switch probability (25% vs. 75%) and found that switching-induced flexibility generalizes to new items, but arguably not to new tasks. This task-specific effect is rather short-lived, limited to the first free-choice trial following a forced-choice trial. Underlying mechanisms of switching-induced flexibility, the versatility of flexibility and implications for the trainability of cognitive flexibility are discussed. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Reducing mean first passage times with intermittent confining potentials: a realization of resetting processes

During a random search, resetting the searcher’s position from time to time to the starting point often reduces the mean completion time of the process. Although many different resetting models have been studied over the past ten years, only a few can be physically implemented. Here we study theoretically a protocol that can be realised experimentally and which exhibits unusual optimization properties. A Brownian particle is subject to an arbitrary confining potential v(x) that is switched on and off intermittently at fixed rates. Motion is constrained between an absorbing wall located at the origin and a reflective wall. When the walls are sufficiently far apart, the interplay between free diffusion during the ‘off’ phases and attraction toward the potential minimum during the ‘on’ phases give rise to rich behaviours, not observed in ideal resetting models. For potentials of the form v(x) = k|x − x 0| n /n, with n > 0, the switch-on and switch-off rates that minimise the mean first passage time (MFPT) to the origin undergo a continuous phase transition as the potential stiffness k is varied. When k is above a critical value k c, potential intermittency enhances the target encounter: the minimal MFPT is lower than the Kramer time and is attained for a non-vanishing pair of switching rates. We focus on the harmonic case n = 2, extending previous results for the piecewise linear potential (n = 1) in unbounded domains. We also study the non-equilibrium stationary states emerging in this process.

Steady-state running rate sets the speed and accuracy of accumulation of swimming bacteria

We study the chemotaxis of a population of genetically identical swimming bacteria undergoing run and tumble dynamics driven by stochastic switching between clockwise and counterclockwise rotation of the flagellar rotary system, where the steady-state rate of the switching changes in different environments. Understanding chemotaxis quantitatively requires that one links the measured steady-state switching rates of the rotary system, as well as the directional changes of individual swimming bacteria in a gradient of chemoattractant/repellant, to the efficiency of a population of bacteria in moving up/down the gradient. Here we achieve this by using a probabilistic model, parametrized with our experimental data, and show that the response of a population to the gradient is complex. We find the changes to the steady-state switching rate in the absence of gradients affect the average speed of the swimming bacterial population response as well as the width of the distribution. Both must be taken into account when optimizing the overall response of the population in complex environments.

Is more competition better? Retail electricity prices and switching rates in the European Union

The European Union (EU) promotes the liberalization of retail electricity markets to achieve lower prices, diversified offers, greater customer participation, and sustainable consumption behaviours. While retail competition has been a reality in most EU member states, most studies find that retail competition is suitable for large customers, but the evidence on small customers is inconclusive. We analyze data on electricity prices and switching rates in 27 EU member states and the UK from 2000 to 2019. We find that retail competition is associated with lower prices and that the effect of full liberalization is greater than that of partial liberalization.

Propagation characteristics of hydrogen-air rotating detonation wave in disk-shaped combustors with different configurations

Experiments are performed to investigate the propagating characteristics of rotating detonation fueled by hydrogen in disk-shaped combustors with different configurations. Three combustor configurations are employed in the experiments, and the channel convergence ratio is ranged from 1.0 to 2.61. The mass flow rate varies from 50 to 450 g/s, and the equivalence ratio is ranged from 0.4 to 2.75. The operation maps including single-wave, symmetric dual-wave, asymmetric dual-wave and triple-wave rotating detonation mode are plotted in this study. The results indicate that the propagation process of rotating detonation wave is more stable when the combustor channel area remains constant. Engine exit convergence is beneficial to increase the intensity of rotating detonation wave and detonation-wave parameters, but “two-plane wall” engine with excessive radial-part convergence ratio would reduce the detonation combustion efficiency, thereby reducing the detonation-wave parameters. Additionally, adding exit convergence or increasing the radial-part convergence makes the wave structure in the rotating detonation combustor more complex. The wave-head number in the combustor increases with an increase in the mass flow rate. At some special conditions, the asymmetric dual-wave mode and triple-wave mode are obtained in the combustor with large radial-part convergence ratio or adding exit convergence. For one propagation mode, its operating scope under the three configurations partially coincides, but the upper and lower limits of equivalence ratio and the operating scope of mass flow rate are greatly affected by the combustor configuration. Adding exit convergence can reduce the critical mass flow rate of modes switching, and broaden the stable operation range of the engine, but the “two-plane wall” engine with excessive radial-part convergence ratio could reduce the operating stability and its operating range.

Adherence, persistence and switching rates of apixaban, dabigatran and rivaroxaban in non-valvular atrial fibrillation: a multicentre real-life analysis at 3 years

IntroductionAdherence to and persistence with long-term treatment with oral anticoagulants play a significant role in preventing adverse events and mortality in patients with cardiac conditions. The aim of this study...

Effect of right hemispheric damage on structured spoken conversation.

Patients with right hemisphere damage (RHD) occasionally complain of difficulties in conversation. A conversation is a type of communication between the speaker and listener, and several elements are required for a conversation to take place. However, it is unclear which of those elements affect communication in patients with RHD. Therefore, we prospectively enrolled 11 patients with right hemispheric damage due to acute cerebral infarction, within 1 week of onset. To evaluate patients’ conversational abilities, we used a structured conversation task, namely, the “Hallym Conversation and Pragmatics Protocol”. The topics of conversation were “family”, “leisure”, and “other/friends”. The conversation characteristics were classified according to three indices: the “conversational participation index”, “topic manipulation index”, and “conversational breakdown index”. Patients with RHD were compared with 11 age-, sex-, and years of education-matched healthy adults. The most common site of damage in the patients with RHD was the periventricular white matter. There was no significant difference in performance between the two groups according to the conversation participation index and in the discontinuance rate assessed with the conversational breakdown index. However, patients with RHD showed a lower topic maintenance rate and higher topic initiation and topic switching rates, according to the topic manipulation index. Therefore, we explored the characteristics of impaired conversation abilities in patients with RHD by assessing their ability to converse and manage topics during structured conversations, and found difficulties with pragmatics and communication discourse in these patients.

Do nudges increase consumer search and switching? Evidence from financial markets

AbstractAs nudge interventions have become more popular, academic research is developing that assesses to what extent these interventions are effective. My paper contributes to this stream of research: collating and synthesising evidence on the effectiveness of nudge interventions that aim to increase consumer search and switching in retail financial markets. Following a systematic search strategy, I identify 35 relevant papers, including qualitative studies, laboratory experiments, field experiments and ex post analyses, covering a range of retail financial products and different types of nudges. The review results in two main contributions. First, it demonstrates that different study designs serve different purposes in evidence accumulation. Second, based on over 400 estimates extracted from these papers, it establishes that the currently available evidence shows that nudges increase consumer search and switching in retail financial markets by 2–3 percentage points on average. Structural nudges that change the choice architecture more profoundly have a higher impact on search and switching than nudges that provide, simplify or highlight information. While nudge interventions may be efficient on a cost–benefit basis and can lead to a large increase in relative terms (e.g. doubling switching rates from 1% to 2%), regulators cannot expect them to significantly alter consumer behaviour.

LB912 Racial/ethnic differences in biologic treatment patterns among patients in the CorEvitas Psoriasis Registry

Racial disparities impacting management of psoriasis patients are incompletely understood. The objective of this study was to assess biologic discontinuation and switching rates after 6-months of therapy among psoriasis patients of different racial/ethnic backgrounds in the US/Canadian CorEvitas Psoriasis Registry. This study included patients who initiated a biologic between April 2015-March 2021 and had a known treatment status at 6-months follow-up. Patient characteristics at initiation were compared by race/ethnicity.

Systematic Review of Real-World Treatment Patterns of Oral Antipsychotics and Associated Economic Burden in Patients with Schizophrenia in the United States.

BackgroundSchizophrenia is a chronic mental disorder associated with substantial morbidity and mortality affecting 0.25–1.6% of adults in the USA. Antipsychotic treatment is the standard of care for schizophrenia, but real-world treatment patterns and associated costs have not been systematically reviewed.ObjectiveWe conducted a systematic review to summarize treatment patterns and associated costs related to oral antipsychotic treatment of patients with schizophrenia in the USA.Data SourcesWe searched Medline (via PubMed) and Embase to identify relevant observational studies published from January 1, 2008, to June 1, 2018; costs were converted to 2018 US dollars.Study EligibilityObservational, real-world studies reporting on patterns of treatment and/or associated costs for adult patients with schizophrenia treated with oral antipsychotics in the USA were included.ResultsEighty-one studies were identified. Frequently prescribed oral second-generation antipsychotics were olanzapine (up to 50.9%), risperidone (up to 40.0%), and quetiapine (up to 30.7%). Suboptimal adherence was common across studies. Antipsychotic switching occurred in about half of patients, while antipsychotic combination therapy occurred in nearly 30%; all were associated with increased medication-related costs. Mean annual direct medical costs differed by treatment, with reported costs of $17,115 to $26,138 for patients treated with olanzapine, $18,395 for risperidone, and $17,656 to $28,101 for quetiapine.LimitationsThis systematic review is limited by the variations in definitions of schizophrenia-related clinical terms used between studies and by the inclusion of studies focused on only the US health care system.ConclusionsIn the treatment of schizophrenia, suboptimal adherence, antipsychotic switching, and antipsychotic augmentation were all associated with high costs of care in comparison to patients who were adherent and did not require antipsychotic switching or augmentation. These findings illustrate the need for the development of new treatments that address efficacy and adherence challenges of currently available therapies.Supplementary InformationThe online version contains supplementary material available at 10.1007/s12325-022-02232-z.

Local bifurcation with spin-transfer torque in superparamagnetic tunnel junctions

Modulation of the energy landscape by external perturbations governs various thermally-activated phenomena, described by the Arrhenius law. Thermal fluctuation of nanoscale magnetic tunnel junctions with spin-transfer torque (STT) shows promise for unconventional computing, whereas its rigorous representation, based on the Néel-Arrhenius law, has been controversial. In particular, the exponents for thermally-activated switching rate therein, have been inaccessible with conventional thermally-stable nanomagnets with decade-long retention time. Here we approach the Néel-Arrhenius law with STT utilising superparamagnetic tunnel junctions that have high sensitivity to external perturbations and determine the exponents through several independent measurements including homodyne-detected ferromagnetic resonance, nanosecond STT switching, and random telegraph noise. Furthermore, we show that the results are comprehensively described by a concept of local bifurcation observed in various physical systems. The findings demonstrate the capability of superparamagnetic tunnel junction as a useful tester for statistical physics as well as sophisticated engineering of probabilistic computing hardware with a rigorous mathematical foundation.

Observation of nonlinearity-controlled switching of topological edge states

Abstract We report the experimental observation of the periodic switching of topological edge states between two dimerized fs-laser written waveguide arrays. Switching occurs due to the overlap of the modal fields of the edge states from topological forbidden gap, when they are simultaneously present in two arrays brought into close proximity. We found that the phenomenon occurs for both strongly and weakly localized edge states and that switching rate increases with decreasing spacing between the topological arrays. When topological arrays are brought in contact with nontopological ones, switching in topological gap does not occur, while one observes either the formation of nearly stationary topological interface mode or strongly asymmetric diffraction into the nontopological array depending on the position of the initial excitation. Switching between topological arrays can be controlled and even completely arrested by increasing the peak power of the input signal, as we observed with different array spacings.

Arrival time for the fastest among N switching stochastic particles

The first arrivals among N Brownian particles is ubiquitous in the life sciences, as it often triggers cellular processes from the molecular level. We study here the case where stochastic particles, which represent proteins or molecules can switch between two states inside the non-negative real line. The switching process is modeled as a two-state Markov chain and particles can only escape in state 1. We estimate the fastest arrival time by solving asymptotically the Fokker–Planck equations for three different initial distributions: Dirac-delta, uniformly distributed and long-tail decay. The derived formulas reveal that the fastest particle avoids switching when the switching rates are much smaller than the diffusion time scale, but switches twice when the diffusion in state 2 is much faster than in state 1. The present results are compared to stochastic simulations revealing the range of validity of the derived formulas.

A Five-Level Nested Diode-Clamped Converter for Medium-Voltage Applications

This article presents a new three-phase five-level converter topology with a single dc source. The proposed topology combines the features of the conventional flying capacitor multicell and diode-clamped multilevel topologies. An important advantage of the proposed topology is the reduced volt-ampere, and hence, the volume, of the flying capacitors in its structure while keeping the same voltage blocking capability for semiconductor switches. The appropriate modulation strategy along with the flying capacitor voltage balancing technique is presented. To show the advantages of the proposed converter, different performance criteria such as switch count and rating, volt-ampere of flying capacitors, component cost, losses, and switching frequency are compared with some existing five-level topologies with a single dc source and the same voltage rating of switches. The results indicate that the proposed structure is superior to other five-level converters from different standpoints of the performance criteria. Simulation results are shown to verify the converter operation and its performance. The validity of the theoretical analysis is verified by experimentation on a scaled-down prototype system.

Fast and efficient demultiplexing of single photons from a quantum dot with resonantly enhanced electro-optic modulators

We report on a multi-photon source based on active demultiplexing of single photons emitted from a resonantly excited GaAs quantum dot. Active temporal-to-spatial mode demultiplexing is implemented via resonantly enhanced free-space electro-optic modulators, making it possible to route individual photons at high switching rates of 38 MHz. We demonstrate routing into four spatial modes with a high end-to-end efficiency of ≈ 79% and measure a four-photon coincidence rate of 0.17 Hz mostly limited by the single-photon source brightness and not by the efficiency of the demultiplexer itself. We use the demultiplexer to characterize the pairwise indistinguishability of consecutively emitted photons from the quantum dot with variable delay time.