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Understanding the dynamics of hot, highly energetic electrons resulting from nonradiative plasmon decay is crucial for optimizing applications in photocatalysis and energy conversion. This study presents an analysis of electron kinetics within plasmonic metals, focusing on the steady-state behavior during continuous-wave (CW) illumination. Using an inelastic spectroscopy technique, we quantify the temperature and lifetimes of distinct carrier populations during excitation. A significant finding is the monotonic increase in hot electron lifetime with decreases in electronic temperature. We also observe a 1.22× increase in hot electron temperature during intraband excitation compared to interband excitation and a corresponding 2.34× increase in carrier lifetime. The shorter lifetimes during interband excitation are hypothesized to result from direct recombination of nonthermal holes and hot electrons, highlighting steady-state kinetics. Our results help bridge the knowledge gap between ultrafast and steady-state spectroscopies, offering critical insights for optimizing plasmonic applications.

Advancements in thermophotovoltaic (TPV) technologies enable a new alternative for the electrification of nuclear power. These solid-state heat engines are more robust and likely cheaper to manufacture than the turbomachinery used in traditional microreactor concepts. The Radiantly Integrated TPV-microreactor system (RITMS) described in this work takes a novel approach to utilizing direct electric conversion of thermal power radiated from the active core. Without intermediary energy transfer, this direct coupling allows for system efficiencies well above 30%. While providing an introduction to the concept, the early RITMS work lacked an integrated computational sequence and economics-by-design approach, resulting in a failure to fully capture the physics of the system or to properly evaluate design parameter importance. The primary purpose of this paper is to describe and demonstrate a computational sequence that fully couples the conductive-radiative heat transfer with a neutronic solution and to provide design-specific cost estimation. This new computational framework is deployed in re-examining the multi-physics behavior of the RITMS design and to perform consistent trade-off studies. A favorable RITMS design was selected based on performance and fuel cycle costs, which was deemed feasible when considering cost uncertainty. Able to operate on 7% enriched fuel, this RITMS case was selected to balance fuel utilization with total power output. [ABSTRACT FROM AUTHOR]

Introduction Smoking cessation is a critical public health goal. This study examined the ability of e-cigarettes and very low nicotine cigarettes (VLNCs) to serve as cigarette substitutes and whether a substitution was supported by steady-state nicotine from a nicotine patch. Aims and Methods This mixed design experiment with study product (between-subjects) and patch (within-subjects) factors recruited adults smoking cigarettes daily and not motivated to quit (N  = 160). Participants were randomized to 4 weeks of: (1) VLNCs; (2) e-cigarettes; or (3) no product. During two switch weeks, one with an active nicotine patch and one with a placebo patch (in a double-blind and counterbalanced fashion), participants were told to not smoke their usual cigarettes. Results During the switch weeks, participants in the VLNC (M  = 2.88, SD = .65) and e-cigarette (M  = 3.20, SD = .63) groups smoked fewer of their own cigarettes per day than did no product group participants who continued to smoke their own cigarettes (M  = 5.48, SD = .63); the VLNC and e-cigarette groups did not differ. There was no main effect of patch on mean usual brand cigarettes smoked per day (P  = .09), nor was there a product × patch interaction (P  = .51). There was a product × age interaction (P  = .03); smokers aged 60–74 smoked more of their own cigarettes if they were randomized to no product group. Conclusions VLNCs and e-cigarettes appear to reduce usual brand cigarettes smoked per day to a similar degree, regardless of patch condition. Behavioral factors, in addition to nicotine dependence, play an important role in sustaining smoking behavior and need to be addressed in smoking cessation treatment. Implications This study found that behavioral substitutes for cigarettes, whether or not they delivered nicotine, reduced the number of usual brand cigarettes smoked. Specifically, both e-cigarettes delivering nicotine and VLNCs equally reduce usual brand cigarettes smoked among adults who smoke daily and do not want to quit. [ABSTRACT FROM AUTHOR]

Background and Objective Inflammatory bowel disease (IBD) fatigue aetiology is poorly understood. This study quantified body composition and physical function alongside proton magnetic resonance imaging (1H MRI) and spectroscopy (31P MRS) measures of organ structure and function in quiescent Crohn's disease patients (CD) and healthy volunteers (HVs), to identify a physiological basis for IBD fatigue. Methods Body composition was determined using dual-energy X-ray absorptiometry and 1H MRI. Knee extensor isometric strength and isokinetic fatigue were measured using dynamometry. 1H MRI was used to quantify cardiac output, cerebral blood flow (gmCBF), and brain oxygen extraction fraction (OEF) at rest, and during supine, steady-state exercise, and recovery. 31P MRS was used to quantify post-exercise muscle phosphocreatine (PCr) resynthesis. Results Sixteen CD and 12 HV (age, sex, and BMI matched) were recruited. Fatigue perception was greater (13.9 ± 1 vs 8.3 ± 0.9, P  = .001), and daily step count was less (5482 ± 684 vs 8168 ± 1123, P  = .04) in CD. During steady-state exercise, gmCBF was less in CD (653 ± 30 vs 823 ± 40 mL/min, P  = .003). Cardiac output and brain OEF were no different. Post-exercise PCr resynthesis was less in CD (17.2 ± 2.0 vs 25.3 ± 2.4 mM·min−1, P  = .02). Body composition, isometric strength, and isokinetic fatigability were no different. Conclusions CD self-reported increased fatigue perception and exhibited a slower rate of post-exercise PCr resynthesis compared to HV. This occurred independently of changes in body composition, muscle strength, and fatigability. IBD fatigue may be linked to peripheral muscle deconditioning and lower gmCBF during submaximal exercise. [ABSTRACT FROM AUTHOR]

The heterogeneity in clinical presentations in sickle cell disease (SCD) alters between crisis and steady state phases. Considering the pathophysiology, it is crucial to establish a disease-specific reference interval for hematological and biochemical parameters and identify the sensitive predictive markers for crisis. The case–control study included fifty-four healthy control, forty SCD cases in crisis state, and forty-six steady state cases. Blood samples were evaluated for complete blood count (CBC) and biochemical parameters. Red cell indices were calculated. 2.5th and 97.5th percentile values were delineated in the steady state cases as new reference interval. The new cut-off values were evaluated for sensitivity and specificity. The steady state cases reported a significant decrease in urea, sodium, Hb, Hct, and RBC count compared to the control group, whereas potassium, and red cell indices were higher. Compared to the steady state, the crisis state depicted a significant increase in urea, liver enzymes, leucocytes, inflammatory indices, and all red cell indices, whereas sodium, albumin, iron, Hb, Hct, and LMR were decreased. The revised 95 percentile ranges were sodium-132.35–143.65 mmol/L, potassium-3.75–6.09 mmol/L, albumin-2.9–5.0 g/dL, Hb-7.51–12.17 g/dL, RBC count-2.2–5.49 × 106/µL, and Hct-22.54–36.1%. Red cell indices like Ricerca, Green and King, and Huber–Heklotz could be good screening tools for crisis events with more than 70% sensitivity. Thus, the laboratory must derive a new reference interval and cut-off values at the steady state in the SCD population it is catering samples rather than comparing it with normal healthy individuals. [ABSTRACT FROM AUTHOR]

Due to the differences in viability, behaviour and immunity of hosts and vectors of different biological ages, and the prevalence of asymptomatic infected individuals, a vector–host infectious disease model with biological age and asymptomatic infections is proposed. The exact expression of the basic reproduction number $ \mathcal {R}_0 $ R0 is derived. Further, we prove that the disease-free steady state is globally asymptotically stable if $ \mathcal {R}_0 \lt 1 $ R0<1, in this case, the disease does not depend on the initial value and always dies out. Further, if $ \mathcal {R}_0 \gt 1 $ R0>1, model admits a unique endemic steady state which is local asymptotical stable under some conditions. Finally, the theoretical results are explained by some numerical simulations. Numerical simulations also show that the duration of asymptomatic infections has an important impact on the number of confirmed cases, and a long duration can significantly reduce the number of confirmed cases. The rational use of asymptomatic infections has a positive effect on the response to the transmission of vector-borne diseases. [ABSTRACT FROM AUTHOR]

Measurements of slope displacements can be effective tools for the early warning of the collapse of slopes under excavation in construction projects in mountainous areas, while evaluating of instability based on measured displacement has not yet been accomplished for slopes under excavation. Measurements of displacements on sandy soil slopes under multistep excavation were made, and the measured data were analyzed to determine the characteristics of creep deformation of the slope during and after the excavation and to establish a procedure for evaluating instability of the slope under excavation in this paper. The following facts were derived from the examination of the measured data. Displacement was generated significantly in the latter stage of excavation, and it was generated not only during excavation but also after excavation. The ratio of the displacement after excavation to that from the start of the excavation to the start of the next excavation became larger as the displacement developed immediately before failure. It indicates that creep displacement after the excavation was more significant at latter excavation just prior to failure. The normal displacement converged to constant as the shear displacement increased under a steady state immediately before the failure in direct shear conditions, and the normal displacement can be an indicator of the instability of the slope. The normal displacement cannot remain constant when the inclination of the slope surface is different from that of the slip surface in the excavated slope in this paper. Different indicators are necessary in this case. The angle α between the slope surface and synthetic displacement (RD) on the slope derived from measured data was introduced instead of normal displacement. The synthetic displacement (RD) on the slope indicated the scalar of the synthesis of the displacements normal and downward to the surface of the slope and surface displacement. It converged to constant after excavation immediately before failure, and shear displacement showed an accelerative increase for constant α. This indicated that the angle α could be an indicator of the instability of the slope. This result showed that the angle α being constant indicated that the stress condition was almost in failure and the displacement increased acceleratively. Further examinations based on the measured data on other slope under excavation should be necessary for confirming the results in this paper based on only a case of experiment. [ABSTRACT FROM AUTHOR]

Myocardial ischemia (MI) in children living with sickle cell anemia (SCA) is rarely reported. MI among children living with this disease could portend untoward outcomes on their quality of life and survival. This study evaluated the prevalence and associated risk factors of MI in children living with SCA during a vaso-occlusive crisis (VOC) compared with those with SCA who had no symptoms nor an MI in the past (those in "steady state") in Lagos, Nigeria. This comparative cross-sectional study was conducted over 10 months (between March and December 2019) among 250 children living with SCA aged 6 months–18 years (125 in VOC and 125 age and sex-matched controls in steady state). The assessment of MI was determined by measuring cardiac troponin T (cTnT) and electrocardiography (ECG). The prevalence of MI measuring cTnT alone in children with SCA during VOC and steady state was 42.4% and 23.2%, respectively. Comparatively, measuring ECG alone, the prevalence of MI in VOC and steady state was 40.8% and 20.8%, respectively. The prevalence of MI measuring cTnT and ECG in children with SCA in VOC and steady state was 38.4% and 20%, respectively. Older age, severity of pain, longer duration of illness, frequent crises per year, elevated white blood cells, and platelet count were significantly associated with MI in participants with SCA. However, with multivariate analysis, age, severity of pain, and elevated platelet counts remained significantly associated with the occurrence of MI. This study affirms the high prevalence of MI in children with SCA irrespective of the diagnostic criteria. Routine evaluation should be done in this cohort to avert MI-associated sequelae. [ABSTRACT FROM AUTHOR]

This paper involves a diffusive epidemic model whose domain has one free boundary with the Stefan boundary condition, and one fixed boundary subject to the usual homogeneous Dirichlet or Neumann condition. By using the standard upper and lower solutions method and the regularity theory, we first study some related steady-state problems which help us obtain the exact longtime behaviors of solution component (u, v). Then we prove there exists the unique classical solution whose longtime behaviors are governed by a spreading-vanishing dichotomy. Lastly, the criteria determining when spreading or vanishing happens are given with respect to the basic reproduction number R 0 , the initial habitat [ 0 , h 0 ] , the expanding rates μ 1 and μ 2 as well as the initial function (u 0 , v 0) . The criteria reveal the effect of the cooperative behaviors of agents and humans on spreading and vanishing. [ABSTRACT FROM AUTHOR]

We study an avascular spherical solid tumour model with cell physiological age and resource constraints in vivo. We divide the tumour cells into three components: proliferating cells, quiescent cells and dead cells in necrotic core. We assume that the division rate of proliferating cells is nonlinear due to the nutritional and spatial constraints. The proportion of newborn tumour cells entering directly into quiescent state is considered, since this proportion can respond to the therapeutic effect of drug. We establish a nonlinear age-structured tumour cell population model. We investigate the existence and uniqueness of the model solution and explore the local and global stabilities of the tumour-free steady state. The existence and local stability of the tumour steady state are studied. Finally, some numerical simulations are performed to verify the theoretical results and to investigate the effects of different parameters on the model. [ABSTRACT FROM AUTHOR]

Currently, the yeast Yarrowia lipolytica is regarded as one of the most promising producers of protein, lipids, polyols, organic acids, and other metabolites. The objective of enhancing the efficiency of the target product biosynthesis can be achieved through the improvement of the strains-producers and the optimization of the cultivation conditions. The present review assesses the potential of continuous cultivation methods (chemostat, turbidostat, pH-auxostat, changestats, etc.) in order to gain insight into the impact of strains and cultivation conditions on the productivity of the developed bioprocesses. The utilization of continuous cultivation methods enables the implementation of processes under controlled and reproducible conditions, thus stabilizing the parameters of the cultivation and the physiological state of the producer, and obtaining homogeneous samples. The review focuses on nitrogen-limited chemostat cultures, which represent the most commonly employed strategy for investigating the physiological and biochemical characteristics of the yeast Y. lipolytica and for developing the processes for the production of lipids, erythritol, citric acid, and recombinant proteins. To date, such an analysis of the literature has not been conducted in the context of the yeast Y. lipolytica. [ABSTRACT FROM AUTHOR]

A partitioned weighted moving average (PWMA) chart is developed by partitioning the samples (or observations) into two groups, calculating the groups' weighted average and adding them. This partitioning gives more control over weight distribution in the most recent j (= 2, 3, ...) samples. The PWMA, exponentially weighted moving average (EWMA) and homogenously weighted moving average (HWMA) charts are compared. For zero state, the PWMA chart outperforms the EWMA and HWMA charts for most (n, λ, δ) values and the outperformance of the former over the two latter charts increases with the time period (j), employed in the partitioning. Here, λ is the charts' smoothing constant and δ is the shift size (multiples of standard deviation). For steady state, the PWMA chart (regardless of j) generally outperforms the EWMA chart in detecting a small shift (δ = 0.25) when the smoothing constant λ ≥ 0.2 for the sample size n = 1; while a larger λ is needed for n = 5. Moreover, for steady state, the PWMA chart outperforms the HWMA chart in detecting small and moderate shifts (0.25 ≤ δ ≤ 1), regardless of (λ, n, j). The PWMA chart demonstrates robustness to non-normality and estimated process parameters. [ABSTRACT FROM AUTHOR]

In this paper, the dynamic behavior of a diffusive Rosenzweig-MacArthur (R-M) predator-prey model with hyperbolic tangent functional response and fear effect was investigated. For the local system, we gave a detailed classification of equilibria and performed bifurcation analysis. It was shown by numerical simulation that both the capture rate and fear factor have a stabilizing effect. Furthermore, the existence of limit cycles was discussed when the prey was in low fear or carrying capacity was sufficiently large. For the reaction-diffusion system, we considered the local stability of a unique positive equilibrium, Turing instability of both positive equilibrium and homogeneous periodic orbits under weak fear effect or strong carrying capacity, the direction of Hopf bifurcation and the stability of bifurcating periodic solutions under small fear cost and large diffusion coefficients, as well as the existence of positive nonconstant steady states. However, in the absence of fear effect, Turing instability of both positive equilibrium and homogeneous periodic orbits did not occur. Meanwhile, numerical examples were given to illustrate the corresponding analytic results.

Abstract A versatile framework is introduced for determining optimal steady‐state operating points for wind turbine control. The framework is based on solving constrained optimization problems at fixed wind speeds and allows for systematically studying required trade‐offs and parameter sensitivities. It can be used as a basis for many control approaches, for example, to automatically compute optimal schedules for control inputs, steady‐state operating points for model linearization, or reference values for tracking. Steady‐state simulation results are obtained using full nonlinear models to consider complex effects caused by couplings from aerodynamics, structural dynamics, and possibly also hydrodynamics in the case of floating wind turbines. Focusing only on the steady‐state response allows a fast and numerically robust optimization, which makes it especially attractive for co‐design studies. The effectiveness of the framework is demonstrated on two offshore extreme‐scale wind turbines, one floating and one fixed bottom.

The adaptive versions of charting tools are well-established statistical monitoring techniques for detecting unknown changes in the process over a range of shifts. A re-weighted adaptive CUSUM mean (RACUSUM) charting scheme has been proposed in this study for monitoring the range of shifts. The proposed RACUSUM statistic estimates the unknown changes in the ongoing process using an EWMA statistic by plugging in an unbiased shift estimator and choosing a suitable smoothing constant according to the estimated shift to update the slack value of the CUSUM statistic. By employing Monte Carlo simulation using the zero- and steady-state processes, the proposal’s run-length (RL) profiles have been calculated. The proposed RACUSUM chart shows more sensitive behavior under the shift delay process than in the case of zero-state. A comparative analysis between the proposal and competitors has been presented using average RL, extra quadratic loss (EQL), and the relative mean index (RMI) as metrics for 1-sided and 2-sided charting schemes. The robustness of the proposed 2-sided RACUSUM chart against non-normality has also been reported. The proposal’s applicability has been demonstrated using two cases, one from the artificial and the other from a dataset of piston ring manufacturing industrial process.

The aim of this article is to consider a three-dimensional Cauchy problem for the parabolic-elliptic system arising from biological transport networks. For such problem, we first establish the global existence, uniqueness, and uniform boundedness of the strong solution by estimating the derivative of the diagonal permeability tensor with respect to time variable. Moreover, for the diffusion coefficient appropriately large, we demonstrate that the corresponding stationary problem admits a strong solution and that the solution of the Cauchy problem will stabilize to its stationary counterpart in infinite time with a time-decay rate.

Abstract Sickle cell disease is a rare genetic disease resulting from an abnormality in hemoglobin. Hemostasis in the steady state, defined as ≥2 months without vaso‐occlusive crises, is poorly described in the literature. We report the routine hemostasis profile in steady state patients with sickle cell disease (SCD), including during pregnancy and according to phenotype. This retrospective study collected data over the period 2010 to 2021. Data on routine hemostasis parameters (prothrombin time [PT] activated partial thromboplastin time [aPTT], and platelets) were collected from medical records and were compared with laboratory norms including during pregnancy; the HbSS phenotype was compared with the HbSC, HbSB°thalassemia, and HbSB+thalassemia phenotypes. we included 119 adults (representing 190 day‐hospitals) with SCD who had attended at least one checkup in the steady state. Seven patients (15 day‐hospitals) on anticoagulants were excluded. Eleven (17 day‐hospitals) were pregnant. Mean routine hemostasis parameters were within normal values regardless of pregnancy. Mean PT was lower during pregnancy (12.3 ± 0.6 s vs. 13.2 ± 1.0 s; P = .01). PT and platelet counts were higher (P = .01) and aPTT was lower (P = .03) in men and nonpregnant women in the HbSS group compared with those in the HbSC group. routinely collected hemostasis parameters in steady state patients were within normal laboratory values, including in pregnant women. PT values differed significantly between pregnant women and nonpregnant women, and PT, aPTT, and platelet counts differed between HbSS, HbSC, and HbSB+thalassemia phenotypes.

Understanding and accurately determining battery cell properties is crucial for assessing battery capabilities. Electrochemical impedance spectroscopy (EIS) is commonly employed to evaluate these properties, typically under controlled laboratory conditions with steady‐state measurements. Traditional steady‐state EIS (SSEIS) requires the battery to be at rest to ensure a linear response. However, real‐world applications, such as electric vehicles (EVs), expose batteries to varying states of charge (SOC) and temperature fluctuations, often occurring simultaneously. This study investigates the impact of SOC and temperature on EIS in terms of battery properties and impedance. Initially, SSEIS results were compared with dynamic EIS (DEIS) outcomes after a full charge under changing temperatures. Subsequently, DEIS was analysed using combined SOC and temperature variations during active charging. The study employed a commercial 450 mAh lithium‐ion (Li‐ion) cobalt oxide (LCO) graphite pouch cell, subject to a 1C constant current (CC)–constant voltage (CCCV) charge for SSEIS and CC charge for DEIS, with SOC ranging from 50% to 100% and cell temperatures from 10 to 35°C. The research developed models to interpolate battery impedance data, demonstrating accurate impedance predictions across operating conditions. Findings revealed significant differences between dynamic data and steady‐state results, with DEIS more accurately reflecting real‐use scenarios where the battery is not at equilibrium and exhibits concentration gradients. These models have potential applications in battery management systems (BMSs) for EVs, enabling health assessments by predicting resistance and capacitance changes, thereby ensuring battery cells' longevity and optimal performance. [ABSTRACT FROM AUTHOR]

A cluster cum classification hierarchical bit map assisted (CCHBMA) medium access control (MAC) protocol is proposed for the energy-efficient data transmission of wireless sensor networks. The proposed protocol utilizes the advantages of clustering and classification techniques to group similar nodes and efficiently allocate the wireless medium. The hierarchical bit mapping approach is used to provide aggregation-aware data transmission across the network. The dynamic scheduling algorithm adapts to changing the network conditions to improve the network performance. The proposed MAC protocol is evaluated based on simulation analysis and analytical modeling. The performance is compared to existing MAC protocols. The result analysis shows that the proposed MAC protocol shows significant improvement in energy-saving with respect to the existing protocols without compromising the packet delivery ratio. [ABSTRACT FROM AUTHOR]

We study the issue of temperature in a steady system around a black hole event horizon, contrasting it with the appearance of divergence in a thermal equilibrium system. We focus on a spherically symmetric system governed by general relativity, particularly examining the steady state with radial heat conduction. Employing an appropriate approximation, we derive exact solutions that illuminate the behaviors of number density, local temperature, and heat in the proximity of a black hole. We demonstrate that a carefully regulated heat inflow can maintain finite local temperatures at the black hole event horizon, even without considering the back-reaction of matter. This discovery challenges conventional expectations that the local temperature near the event horizon diverges in scenarios of thermal equilibrium. This implications shows that there's an intricate connection between heat and gravity in the realm of black hole thermodynamics. [ABSTRACT FROM AUTHOR]

In this paper, we investigate a reaction–diffusion–advection benthic–drift model, where the population is divided into two interacting groups: individuals dispersing in the drift zone and individuals living in the benthic zone. For different growth types of the benthic population, we present asymptotic profiles of positive steady states in three cases: (i) large advection; (ii) small diffusion of the drift population; and (iii) large diffusion of the drift population. We prove that in case (i) both the benthic and drift individuals concentrate only at the downstream end; in case (ii), both benthic and drift population reside inhomogeneously in (0,L)$(0, L)$, stay away from the upstream end x=0$x = 0$, and concentrate only at the downstream x=L$x = L$; and in case (iii), the drift species distributes evenly on the entire habitat and the benthic species distributes inhomogeneously throughout the habitat. The result supplements the dynamical behaviors of benthic–drift models developed in earlier works and is also of its own interest. [ABSTRACT FROM AUTHOR]

The adaptive versions of charting tools are well-established statistical monitoring techniques for detecting unknown changes in the process over a range of shifts. A re-weighted adaptive CUSUM mean (RACUSUM) charting scheme has been proposed in this study for monitoring the range of shifts. The proposed RACUSUM statistic estimates the unknown changes in the ongoing process using an EWMA statistic by plugging in an unbiased shift estimator and choosing a suitable smoothing constant according to the estimated shift to update the slack value of the CUSUM statistic. By employing Monte Carlo simulation using the zero- and steady-state processes, the proposal's run-length (RL) profiles have been calculated. The proposed RACUSUM chart shows more sensitive behavior under the shift delay process than in the case of zero-state. A comparative analysis between the proposal and competitors has been presented using average RL, extra quadratic loss (EQL), and the relative mean index (RMI) as metrics for 1-sided and 2-sided charting schemes. The robustness of the proposed 2-sided RACUSUM chart against non-normality has also been reported. The proposal's applicability has been demonstrated using two cases, one from the artificial and the other from a dataset of piston ring manufacturing industrial process. [Display omitted] • A new re-weighted adaptive CUSUM (RACUSUM) mean chart is designed to monitor shifts in the interval. • The proposal RACUSUM statistic estimates the unknown shift in the process mean. • The run-length (RL) profiles of the 1-sided and 2-sided proposed RACUSUM charts are evaluated using Monte Carlo simulation. • The extra quadratic loss (EQL) and relative mean index (RMI) metrics have been selected for the shifts in the interval. • The designed structure is applied to real piston ring industrial process data. [ABSTRACT FROM AUTHOR]

A versatile framework is introduced for determining optimal steady‐state operating points for wind turbine control. The framework is based on solving constrained optimization problems at fixed wind speeds and allows for systematically studying required trade‐offs and parameter sensitivities. It can be used as a basis for many control approaches, for example, to automatically compute optimal schedules for control inputs, steady‐state operating points for model linearization, or reference values for tracking. Steady‐state simulation results are obtained using full nonlinear models to consider complex effects caused by couplings from aerodynamics, structural dynamics, and possibly also hydrodynamics in the case of floating wind turbines. Focusing only on the steady‐state response allows a fast and numerically robust optimization, which makes it especially attractive for co‐design studies. The effectiveness of the framework is demonstrated on two offshore extreme‐scale wind turbines, one floating and one fixed bottom. [ABSTRACT FROM AUTHOR]

Lab scale combustion of solid fuels, such as biomass, is mostly performed using fixed bed combustors. Steady state data detailing various progress variables (temperature and emissions) are widely available within the literature. However, there is very little information available on how the onset of the steady state operation is identified especially in relation to batch operation, which is subject to depleting fuel bed. This paper uses experiments coupled with a systemic post-processing approach based on MATLAB in order to identify the onset of the steady state operation. The results show that by using both the percentile mean deviation and slope of certain measured progress variables (including the fuel bed temperature, freeboard temperature, fuel mass loss, and emissions) the steady state regime can be accurately predicted. The use of freeboard temperature data alone is not sufficient. Based on the methods developed, radiation error in thermocouple data was found to be significant in both non-staged and staged air combustion modes of fixed bed combustor. Moreover, the radiation error was lower for downstream thermocouples in contrast to upstream thermocouples. [ABSTRACT FROM AUTHOR]

In this paper, the dynamic behavior of a diffusive Rosenzweig-MacArthur (R-M) predator-prey model with hyperbolic tangent functional response and fear effect was investigated. For the local system, we gave a detailed classification of equilibria and performed bifurcation analysis. It was shown by numerical simulation that both the capture rate and fear factor have a stabilizing effect. Furthermore, the existence of limit cycles was discussed when the prey was in low fear or carrying capacity was sufficiently large. For the reaction-diffusion system, we considered the local stability of a unique positive equilibrium, Turing instability of both positive equilibrium and homogeneous periodic orbits under weak fear effect or strong carrying capacity, the direction of Hopf bifurcation and the stability of bifurcating periodic solutions under small fear cost and large diffusion coefficients, as well as the existence of positive nonconstant steady states. However, in the absence of fear effect, Turing instability of both positive equilibrium and homogeneous periodic orbits did not occur. Meanwhile, numerical examples were given to illustrate the corresponding analytic results. [ABSTRACT FROM AUTHOR]

We consider a time-average estimator fk of a functional of a Markov chain. Under a coupling assumption, we show that the expectation of fk has a limit μ as the number of time steps goes to infinity. We describe a modification of fk that yields an unbiased estimator f^k of μ. It is shown that f^k is square integrable and has finite expected running time. Under certain conditions, f^k can be built without any precomputations and is asymptotically at least as efficient as fk, up to a multiplicative constant arbitrarily close to one. Our approach also provides an unbiased estimator for the bias of fk. We study applications to volatility forecasting, queues, and the simulation of high-dimensional Gaussian vectors. Our numerical experiments are consistent with our theoretical findings. [ABSTRACT FROM AUTHOR]

We propose a reaction-diffusion model to describe the interactive wild and sterile mosquito populations in spatially heterogeneous environments, where the vital dynamics of mosquito populations, e.g., offspring produced per mate, the death rates, the amount of releasing sterile mosquitoes, depend on its location habits and the distribution of wild mosquito populations. First, we show the model may present multiple positive steady states with either Neumann or Dirichlet boundary conditions. Then we investigate the interactive dynamics of mosquito populations with the different initial data. Our results show that wild mosquitoes can be eradicated or suppressed within a certain range with different releasing amounts. Finally, numerical simulations further show that the spatial variability environment within the habitat may play a crucial role in extirpating wild mosquito populations in the context of the sterile insect techniques (SIT). [ABSTRACT FROM AUTHOR]

In this paper, we show the existence of a steady-state solution $ [\rho_0 $, $ u_0\equiv 0 $, $ \Phi_0] $ of the three-dimensional Euler-Poisson-Korteweg system in a bounded domain with physical boundary conditions using calculus of variations. Based on the existence result, the asymptotic stability for the Euler-Poisson-Korteweg system is established near the given steady state. [ABSTRACT FROM AUTHOR]

Objective To analyse the biliary pharmacokinetics/pharmacodynamics (PK/PD) of continuous infusion (CI) meropenem-vaborbactam (MEM-VBM) in a case series of orthotopic liver transplant (OLT) recipients being treated for Klebsiella pneumoniae carbapenemase-producing Klebsiella pneumoniae (KPC-Kp) related biliary tract infections (BTIs) or as preemptive therapy of KPC-Kp rectal colonization. Methods Critical OLT recipients receiving CI MEM-VBM (2 g/2 g q8h over 8 h) because of KPC-Kp related BTIs or as preemptive therapy of KPC-Kp rectal colonization, having Kehr's tube positioned and undergoing simultaneous therapeutic drug monitoring of MEM and VBM in plasma and bile were retrospectively assessed. Bile-to-plasma ratio of free steady-state concentrations (f Css) of MEM and VBM was used for assessing biliary penetration. Optimal joint MEM-VBM PK/PD target attainment was defined as MEM f Css/MIC ratio >4 coupled with VBM free area under time–concentration curve (f AUC)/threshold concentration (CT) ratio >24. Results Overall, four critical OLT recipients were included. Median bile-to-plasma ratio was 0.32 for MEM (range 0.21–0.79) and 0.40 for VBM (range 0.20–0.77). Biliary MEM-VBM joint PK/PD target attainment was optimal in 3/4 OLT recipients and quasi-optimal in the other one. Conclusions The 1:1 proportion between MEM and VBM concentrations was maintained unchanged in the bile, allowing us to assume that the efficacy of MEM-VBM may be appropriate even in the treatment of BTIs. CI administration was an effective strategy for attaining aggressive biliary joint PK/PD targets against pathogens with an MIC up to 2 mg/L. [ABSTRACT FROM AUTHOR]

Objectives Area under the concentration–time curve (AUC)–guided dosing of vancomycin was introduced in a clinical setting; however, the target range of non–steady-state AUCs, such as Day 1 AUC and Day 2 AUC, remains controversial. Therefore, we sought to determine pharmacokinetic parameter thresholds and identify independent risk factors associated with acute kidney injury (AKI) to establish a safe initial dosing design for vancomycin administration. Methods A single-centre, retrospective, cohort study of hospitalized patients treated with vancomycin was conducted to determine the threshold of both non–steady-state AUCs (Day 1 and 2 AUCs) and trough levels at the first blood sampling point (therapeutic drug monitoring, TDM). In addition, independent risk factors associated with AKI were evaluated using univariate and multivariate logistic regression analyses. Results The thresholds for predicting AKI were estimated as 456.6 mg·h/L for AUC0-24h, 554.8 mg·h/L for AUC24-48h, 1080.8 mg·h/L for AUC0-48h and 14.0 μg/mL for measured trough levels, respectively. In a multivariate analysis, Day 2 AUC ≥ 554.8 mg·h/L [adjusted odds ratio (OR), 57.16; 95% confidence interval (CI), 11.95–504.05], piperacillin/tazobactam (adjusted OR, 15.84; 95% CI, 2.73–127.70) and diuretics (adjusted OR, 4.72; 95% CI, 1.13–21.01) were identified as risk factors for AKI. Conclusions We identified thresholds for both AUCs in the non–steady-state and trough levels at the first TDM. Our results highlight the importance of monitoring not only the AUC but also trough levels during vancomycin treatment to reduce the likelihood of AKI. [ABSTRACT FROM AUTHOR]

High velocity oxyfuel coatings have been sprayed on aluminium (Al) alloy composites substrate with varying coating thickness and tested for their wear behavior. The density and micro‐ hardness of the coatings found to increase with increase in coating thickness. The air erosion wear test has been conducted using quartz sand of size up to 75 μm as erodent. The steady state experiments indicate that the greatest specific erosion rate is at 60° and minimum at 30°. Due to the presence of interlayer, specific erosion rate decreases with the increase in the thickness of the coatings. Surface topography of the eroded samples indicate a decrease in surface roughness with increase in impact velocity. Thereafter, Taguchi (L16) orthogonal array has been utilized in order to optimize the input parameters. Analysis of variance has been applied to determine the contribution of individual control factors. The results from Taguchi experiments and analysis of variance find the order of dominance of control factors and their individual contribution as: velocity (47.31 %) > coating thickness (29.94 %) > angle (13.26 %) > erodent feed rate (7.65 %). Coatings have exhibited a semiductile wear behavior. [ABSTRACT FROM AUTHOR]

Folic acid (FA) supplementation in sickle cell disease (SCD) patients lead to accumulation of unmetabolized folic acid (UMFA) which might influence the level of cytokines and NK cell activity and thus trigger the crisis event. The aim of the study was to investigate the effect of UMFA levels on immuno-inflammatory markers in SCD patients taking FA supplementation. The cross-sectional study was conducted on 60 HbSS confirmed SCD cases with 22 crisis and 38 cases at steady state of 15–40 years age group. Serum FA, 5-Methyl Tetrahydrofolate (5-MTHF), Dihydrofolate reductase, Interleukin-6 (IL-6), Highly sensitive C-Reactive Protein (HsCRP), and natural killer (NK) cell activity were estimated. More than 50% of the study population depicted presence of UMFA. The median UMFA level was significantly elevated in crisis group (131.8 ng/mL) as compared to the steady state group (36.31 ng/mL) (p = 0.041). The median value of HsCRP was significantly higher in the crisis group (18.41 mg/L) than the steady state group (2.04 mg/L) (p = 0.003). Similarly, IL-6 was higher in crisis group (13.29 pg/mL) than steady state group (5 pg/mL) (p = 0.060). The median NK cell activity was 39.28 nmol/L in crisis group and 35.31 nmol/L in steady state groups (p = 0.889). In bivariate correlation analysis, UMFA showed a significant negative correlation with NK cell activity (r = − 0.638; p = < 0.001) and a positive correlation with IL-6 (r = 0.571; p = 0.001) and HsCRP (r = 0.237; p = 0.200). Accumulation of UMFA affect NK cell activity, thus influence the vulnerability for crisis state. Therefore, dosage modification for FA supplementation in SCD patients is suggested. [ABSTRACT FROM AUTHOR]

There has been general agreement that grain refinement upon severe plastic deformation (SPD) saturates at equivalent strains of 10–20, as a dynamic equilibrium between refinement and coarsening is established. Meanwhile, few reports question such steady state, but suggest another strain hardening regime might be entered for strains >1000. So far, neither an in‐depth analysis nor a general theory for such ultra‐SPD strain hardening has been established. The present work provides clear evidence for additional strain hardening at ultra‐severe strains. Although at this stage the strain hardening rate is awfully weak (≈0.03 MPa), it manifests in noticeable grain refinement and hardness increase. Texture and the existence of subgrains still support dislocation‐based plasticity. Specimens deformed to ultra‐severe strains possess improved thermal stability. Although an unambiguous conclusion regarding the origin of the ultra‐SPD strain hardening is currently not possible, the potential mechanisms are being discussed. While continuous impurity uptake from the anvils could explain the hardening and improved thermal stability, estimation of grain boundary migration rates suggests that a slight but continuous net refinement is also plausible. Together with structural transformations of grain boundaries, this offers an alternative, intrinsic source for ultra‐SPD hardening. It is hoped that this thought‐provoking conclusion stimulates further research into this subject. [ABSTRACT FROM AUTHOR]

This paper discusses rationalizable self-confirming equilibrium (RSCE) in static games with unawareness that captures steady states of such games. We begin by defining the equilibrium concept in terms of its epistemic conditions. k-RSCE is a situation in which agents make rational choices and have correct beliefs about one another's choices, and moreover these can be mutual belief to the k-th order. We then present an alternative definition that dispenses with these epistemic conditions and allows us to obtain equilibria through iterative eliminations of certain action profiles. In standard static games, k-RSCE reduces to Nash equilibrium, but not under unawareness. We examine the equilibrium concept's properties and clarify its relationships with other equilibrium concepts for games with unawareness. [ABSTRACT FROM AUTHOR]

Task‐related studies have consistently reported that listening to speech sounds activate the temporal and prefrontal regions of the brain. However, it is not well understood how functional organization of auditory and language networks differ when processing speech sounds from its resting state form. The knowledge of language network organization in typically developing infants could serve as an important biomarker to understand network‐level disruptions expected in infants with hearing impairment. We hypothesized that topological differences of language networks can be characterized using functional connectivity measures in two experimental conditions (1) complete silence (resting) and (2) in response to repetitive continuous speech sounds (steady). Thirty normal‐hearing infants (14 males and 16 females, age: 7.8 ± 4.8 months) were recruited in this study. Brain activity was recorded from bilateral temporal and prefrontal regions associated with speech and language processing for two experimental conditions: resting and steady states. Topological differences of functional language networks were characterized using graph theoretical analysis. The normalized global efficiency and clustering coefficient were used as measures of functional integration and segregation, respectively. We found that overall, language networks of infants demonstrate the economic small‐world organization in both resting and steady states. Moreover, language networks exhibited significantly higher functional integration and significantly lower functional segregation in resting state compared to steady state. A secondary analysis that investigated developmental effects of infants aged 6‐months or below and above 6‐months revealed that such topological differences in functional integration and segregation across resting and steady states can be reliably detected after the first 6‐months of life. The higher functional integration observed in resting state suggests that language networks of infants facilitate more efficient parallel information processing across distributed language regions in the absence of speech stimuli. Moreover, higher functional segregation in steady state indicates that the speech information processing occurs within densely interconnected specialized regions in the language network. [ABSTRACT FROM AUTHOR]

The subthalamic nucleus (STN) of the basal ganglia is key to the inhibitory control of movement. Consequently, it is a primary target for the neurosurgical treatment of movement disorders like Parkinson's disease, where modulating the STN via deep brain stimulation (DBS) can release excess inhibition of thalamocortical motor circuits. However, the STN is also anatomically connected to other thalamocortical circuits, including those underlying cognitive processes like attention. Notably, STN-DBS can also affect these processes. This suggests that the STN may also contribute to the inhibition of non-motor activity and that STN-DBS may cause changes to this inhibition. Here we tested this hypothesis in humans. We used a novel, wireless outpatient method to record intracranial local field potentials (LFP) from STN DBS implants during a visual attention task (Experiment 1, n = 12). These outpatient measurements allowed the simultaneous recording of high-density EEG, which we used to derive the steady state visual evoked potential (SSVEP), a well established neural index of visual attentional engagement. By relating STN activity to this neural marker of attention (instead of overt behaviour), we avoided possible confounds resulting from STN's motor role. We aimed to test whether the STN contributes to the momentary inhibition of the SSVEP caused by unexpected, distracting sounds. Furthermore, we causally tested this association in a second experiment, where we modulated STN via DBS across two sessions of the task, spaced at least 1 week apart (n = 21, no sample overlap with Experiment 1). The LFP recordings in Experiment 1 showed that reductions of the SSVEP after distracting sounds were preceded by sound-related γ-frequency (>60 Hz) activity in the STN. Trial-to-trial modelling further showed that this STN activity statistically mediated the sounds' suppressive effect on the SSVEP. In Experiment 2, modulating STN activity via DBS significantly reduced these sound-related SSVEP reductions. This provides causal evidence for the role of the STN in the surprise-related inhibition of attention. These findings suggest that the human STN contributes to the inhibition of attention, a non-motor process. This supports a domain-general view of the inhibitory role of the STN. Furthermore, these findings also suggest a potential mechanism underlying some of the known cognitive side effects of STN-DBS treatment, especially on attentional processes. Finally, our newly established outpatient LFP recording technique facilitates the testing of the role of subcortical nuclei in complex cognitive tasks, alongside recordings from the rest of the brain, and in much shorter time than peri-surgical recordings. [ABSTRACT FROM AUTHOR]

African scientific research faces formidable challenges, particularly with limited access to state-of-the-art measurement instruments. The high cost associated with these devices presents a significant barrier for regional research laboratories, impeding their ability to conduct sophisticated experiments and gather precise data. This predicament not only hampers the individual laboratories but also has broader implications for the African scientific community and the advancement of knowledge in developing nations—the financial cost barrier considerably impacts the research quality of these laboratories. Reflection on technical and economical solutions needs to be quickly found to help these countries advance their research. In civil engineering, the thermal conductivity property is the most important measurement for characterizing heat transfer in construction materials. Existing devices (i.e., conductometers) in a laboratory are expensive (approximately EUR 30,000) and unavailable for some African laboratories. This study proposes a new and affordable device to evaluate thermal conductivity in construction materials. The method involves establishing a thermal flux between a heat source (from the Joule effect provided by steel wool where a current is circulating) and a cold source (generated by ice cubes) under steady-state conditions. The development of the cylindrical prototype is based on the comparative flux-meter method outlined in the measuring protocol of the ASTM E1225 standard document. Experiments were conducted on four distinct materials (polystyrene, wood, agglomerated wood, and rigid foam). The results indicate a correct correlation between the experimental values obtained from the newly developed prototype and the reference values found in the literature. For example, concerning the experimental polystyrene study, the detailed case analysis reveals a good correlation, with a deviation of only 4.88%. The percent error found falls within the acceptable range indicated by the standard recommendations of the ASTM E1225 standard, i.e., within 5% acceptable error. [ABSTRACT FROM AUTHOR]