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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.

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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.

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]

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 agestructured 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]

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.

Indonesia, an archipelagic country, boasts significant potential in the fisheries sector, notably in the export of fishery products. Batam as a free trade zone plays a major role in Indonesia's fishery product exports. According to the Central Statistics Agency's data, there has been a 2.47% decline in fish and shrimp exports in January and February 2023 compared to January 2022. Therefore, further analysis is needed on projected exports of fishery products in Batam. This study focuses on the utilization of the Markov chain model to analyze the export dynamics of Batam City's primary fishery product commodities, including Seaweed, Fish, Shrimp, Crab, and Shellfish. Monthly export data for Batam City's fishery products throughout 2021-2023 sourced from The Ministry of Marine Affairs and Fisheries. Based on these data, the transition probability matrix will be calculated based on the number of export transitions below and above the Moving Average (MA 12) value. The Markov chain model for this case is an erdogic Markov chain model, in order that the limiting probability of the Markov chain model can be determined. The result shows that exports of fish, shrimp and crab in the long term will exceed the average export size in the past year each after 7 months, 11 months, and 14 months later respectively, while exports of seaweed and shellfish in the long term will be below the large average exports in the past year after 15 and 5 months. This research result offer valuable insights for the government to formulate strategies and policies concerning fishery product exports

Arming at the coexistence dilemma of inventory overhang and shortage of different maintenance equipment supply nodes, a steady-state coefficient of a supply node has been described with which contains inventory level, the support degree between nodes each other, the demand status of the area guaranteed by the node and the cost of risk when the demand cannot be met. The steady-state coefficient of the inventory network was calculated on the base of all of support nodes. The active adjustment is carried out flowing the corresponding algorithm according to the gap between the steady-state coefficient and the threshold which has been set before. The scientific, automatic and intelligent level of equipment adjustment can be greatly improved, consequently the success rate of maintenance support is improved if the passive stock adjustment is combined because of out of stock at the same time.

In most of the manufacturing industry, the distributional assumption of the online working processes is customarily unknown or hard to meet. In such situations, parametric charting mechanisms generally designed under normality assumptions of the model yield more false alarms and invalid out-of-control (OOC) comparisons. The nonparametric (distribution-free) charts are a better choice for practitioners in such cases as their in-control (IC) run length (RL) profiles remain the same. The study intends to develop a new distribution-free adaptive CUSUM sign (NPACUSUM-SN; named hereafter) chart for monitoring the process location. The proposed NPACUSUM-SN chart estimates the unknown process mean shift using an unbiased function and updates adaptively the reference parameter of the CUSUM statistic. The IC robustness of the conventional adaptive CUSUM and the proposed NPACUSUM-SN charts under the symmetric, skewed, and contaminated normal (CN) distributions have been computed using Monte Carlo simulations. The OOC RL profiles of the proposed study have been assessed for the initial state and the shift delay (steady state) in the processes. The proposed NPACUSUM-SN chart shows more resistance against non-normality and effective behaviour as compared to its conventional competitor. The proposed NPACUSUM-SN chart provides uniformly efficient RL characteristics as compared to its counterparts. Implementation of the proposal is made by using a manufacturing industry dataset along with an artificial dataset. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the existence and stability of non‐trivial steady‐state solutions of a class of chemotaxis models with zero‐flux boundary conditions and Dirichlet boundary conditions on a one‐dimensional bounded interval. By using upper–lower solution and the monotone iteration scheme method, we get the existence of the steady‐state solution of the chemotaxis model. Moreover, by adopting the "inverse derivative" technique and the weighted energy method, we prove the stability of the steady‐state solution of this chemotaxis model. [ABSTRACT FROM AUTHOR]

Arming at the coexistence dilemma of inventory overhang and shortage of different maintenance equipment supply nodes, a steady-state coefficient of a supply node has been described with which contains inventory level, the support degree between nodes each other, the demand status of the area guaranteed by the node and the cost of risk when the demand cannot be met. The steady-state coefficient of the inventory network was calculated on the base of all of support nodes. The active adustment is carried out flowing the corresponding algorithm according to the gap between the steady-state coefficient and the threshold which has been set before. The scientific, automatic and intelligent level of equipment adjustment can be greatly improved, consequently the success rate of maintenance support is improved if the passive stock adjustment is combined be- cause of out of stock at the same time. [ABSTRACT FROM AUTHOR]

We consider three different systems in a heat flow: an ideal gas, a van der Waals gas, and a binary mixture of ideal gases. We divide each system internally into two subsystems by a movable wall. We show that the direction of the motion of the wall, after release, under constant boundary conditions, is determined by the same inequality as in equilibrium thermodynamics d U − đ Q ≤ 0 . The only difference between the equilibrium and non-equilibrium laws is the dependence of the net heat change, đ Q , on the state parameters of the system. We show that the same inequality is valid when introducing the gravitational field in the case of both the ideal gas and the van der Waals gas in the heat flow. It remains true when we consider a thick wall permeable to gas particles and derive Archimedes' principle in the heat flow. Finally, we consider the Couette (shear) flow of the ideal gas. In this system, the direction of the motion of the internal wall follows from the inequality d E − đ Q − đ W s ≤ 0 , where d E is the infinitesimal change in total energy (internal plus kinetic) and đ W s is the infinitesimal work exchanged with the environment due to the shear force imposed on the flowing gas. Ultimately, we synthesize all these cases within a general framework of the second law of non-equilibrium thermodynamics. [ABSTRACT FROM AUTHOR]

The law of superposition underpins first-order linear pharmacokinetic relationships. Most drugs, therefore, after a single dose can be described by first-order or linear processes, which can be superposed to understand multiple-dose regimen behavior. However, there are a number of situations where drugs could display behaviors after multiple dosing that leads to capacity-limited or saturation non-linear kinetics and the law of superposition is overruled. This review presents a practical guide to understand the equations and calculations for single and multiple-dosing regimens after intravenous and oral administration. It also provides the pharmaceutical basis for saturation in ADME processes and the consequent changes in the area under the concentration–time curve, which represents drug exposure that can lead to the modulation of efficacy and/or toxic effects. The pharmacokineticist must implicitly understand the principles of superposition, which are a central tenet of drug behavior and disposition during drug development. [ABSTRACT FROM AUTHOR]

Nuclear thermal propulsion is an evolving technology that can be utilized for long-distance space travel. This technology yields the advantage of a high thrust and specific impulse, but requires an examination of the potential design adjustments necessary to enhance its feasibility. The development of nuclear thermal propulsion requires a comprehensive understanding of the system-level behavior during transient and steady-state operation. This paper extends our previous research by including the proper handling of turbomachinery with multi-channel thermal hydraulic simulations only for steady-state solutions. The system-level approach presented here enables the treatment of the turbopump components through non-dimensional analysis that eliminates the assumption of constant efficiencies. All the other components within the system (e.g., reflector and core) can be discretized to multiple channels and layers, in which the full thermal hydraulic solution is established. The approach chosen here enables the realistic modeling of the propellant flow within the expander cycle by capturing the pressure losses, mass flow rate splits, and enthalpy gain for various operational conditions. The verification of the package is completed through point comparisons of previous investigations into similar system designs. Furthermore, sensitivity studies are used to benchmark the capabilities of the package and investigate solution variations due to the perturbation of operational conditions and regimes. The sensitivity studies performed here are important to capture variation in flow characteristics (e.g., temperature, pressure, mass flow rates) for different design objectives such as the thrust and specific impulse. This work demonstrates that system-level simulations lacking multi-channel capability and proper turbomachinery treatment may yield higher uncertainties in understanding the engine's response and characteristics to changing various requirements. This is extremely important when screening the design space of such propulsion systems and when transient simulations are required. [ABSTRACT FROM AUTHOR]

Dynamic competition-cooperation models are employed to scrutinize the interplay among products, markets, or services, either in terms of competition or cooperation. Additionally, they serve to predict the behavior of the entities under examination, such as passenger volumes within transportation systems. Utilizing steady-state and asymptotic analyses, researchers delve into the long-term dynamics of these entities. While steady-state analysis delves into equilibrium conditions, asymptotic analysis scrutinizes system behavior as time extends toward infinity. However, the influence of socioeconomic factors, which are external, cannot be disregarded in dynamic competition-cooperation models concerning passenger volumes in transportation systems. These factors typically encompass population dynamics, gross domestic product (GDP), oil prices, unemployment rates, consumer price indices, among others. The primary aim of this study is to assess the stability and asymptotic behavior of dynamic competition-cooperation models in light of economic factors. The investigation reveals that the solutions derived from these models do not exhibit periodic behavior. Rather, the system tends to converge or diverge. Notably, when convergence transpires, it does not converge towards a fixed point but towards a function of the economic factors. This underscores the profound influence of prevailing economic conditions on the behavior of transportation systems. [ABSTRACT FROM AUTHOR]

Consideration has been given to a nonlinear problem of a filtration pressure field in a porous bed operated in a specified depression regime with a one-dimensional radial flow of a compressible medium in it. Solutions have been obtained of a problem for the zeroth and the first expansion coefficients of a nonlinear filtration pressure field, which represent the main and the first asymptotic approximations describing high-amplitude pressure fields in oil and gas beds with a weakly compressible framework. The development of the asymptotic method as applied to the problem under consideration has led to the creation of a new method of constructing analytical expressions for expansion coefficients, which coincides with the method of succession of steady states in solving the problem for the leading approximation. Based on a computational experiment, it has been shown that the pressure field in a porous bed with a weakly compressible framework is most accurately described using the method of succession of steady states, according to which pressure disturbances in the bed are absent at short times. It has been established that with increase in the distance from the well axis the disturbance delay time increases, and the velocity of the buildup of perturbations, caused by the operation of the well in a constant depression mode, decreases. [ABSTRACT FROM AUTHOR]

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Background The clinical candidate alpibectir augments the activity of, and overcomes resistance to, the anti-TB drug ethionamide in vitro and in vivo. Objectives A Phase 1, double-blind, randomized, placebo-controlled study to investigate the safety, tolerability, pharmacokinetics (PK) and food effect of alpibectir administered as single and multiple oral doses in healthy volunteers (NCT04654143). Methods Eighty participants were randomized. In single ascending dose (SAD), a total of six dose levels of alpibectir (0.5 to 40 mg) were tested under fasted and fed (10 mg) conditions as single daily doses in sequential cohorts. In multiple ascending dose (MAD), repeat doses (5 to 30 mg) were administered once daily for 7 days in three sequential cohorts. Results No serious adverse event was reported. Thirteen participants across groups experienced a total of 13 mild or moderate treatment-emergent adverse events. Alpibectir showed rapid absorption after single dose (mean T max range of 0.88 to 1.53 h). Food affected the PK of alpibectir, characterized by a slower absorption (mean T max 3.87 h), a lower C max (−17.7%) and increased AUC0– t (+19.6%) compared with the fasted condition. Following repeat dosing, dose proportionality was shown for both C max and AUC0–tau. Accumulation of alpibectir was observed across all doses, with a more profound effect on AUC during a dosing interval (AUC0–tau) compared with C max (1.8- and 1.3-fold on average), respectively. Steady state was considered to have been achieved by Day 7 of dosing. Conclusions Alpibectir was generally well tolerated, and no clinically relevant safety findings were identified in the participants treated during SAD or MAD. The PK is dose-proportional and affected by food. [ABSTRACT FROM AUTHOR]

This paper provides information on the performance study of precision current shunts in the context of their output voltage stability. Besides, it briefly focuses on the phenomena affecting the steady state of these measuring instruments. The authors present a methodology for testing current shunts to ensure a high-quality result of current measurement. The investigation highlights three characteristics of shunts (the dependence of resistance on temperature, the response of the output voltage to a fast increase of current, and the transition from a cold state to a warm one). The test equipment with precision shunts were considered during the experimental examination. The results of an investigation confirmed satisfactory operational properties and compliance with the needs of laboratories. Additionally, the authors emphasize using a precision shunt as a measuring standard when calibrating other instruments like high-precision digital ammeters. From this point of view, the simplified mathematical modeling of the change in the AC-DC transfer difference, depending on the resistance change caused by the warming current, was carried out. [ABSTRACT FROM AUTHOR]

Understanding the state transitions in biological systems and identifying critical steady states are crucial for investigating disease development and discovering key therapeutic targets. To advance the study of state transitions in specific biological entities, we proposed the Ternary Entity State Inference System (T-ESIS). T-ESIS builds upon the Entity State Inference System by providing richer information on entity states, where states can take values of 0, 1, or 1/2, representing activation, inhibition, and normal states, respectively. This method infers state transition pathways based on interaction relationships and visualizes them through the Entity State Network. Furthermore, the cyclic structures within the Entity State Network capture positive and negative feedback loops, providing a topological foundation for the formation of steady states.To demonstrate the applicability of T-ESIS, entity states were modeled, and attractor analysis was conducted in non-small cell lung cancer (NSCLC) networks. Our analysis provided valuable insights into targeted therapy for NSCLC, highlighting the potential of T-ESIS in uncovering therapeutic targets and understanding disease mechanisms. Moreover, the proposed T-ESIS framework facilitated the inference of entity state transitions and the analysis of steady states in biological systems, offering a novel approach for studying the dynamic principles of these systems. This ternary dynamic modeling approach not only deepened our understanding of biological networks but also provided a methodological reference for future research in the field.

As an archipelagic country, Indonesia has great potential in the fisheries sector. As a free trade zone, Batam is important in exporting fishery products. One of the fishery export products in Batam City is gonggong snails. It is a favorite seafood item in Riau Islands Province and has high economic value. However, previous studies focused more on the content of gonggong snails and their industrial feasibility; there has been no specific research on the analysis of gonggong snail exports in Batam City, even though gonggong snails are one of Batam City's export products. In this research, we will forecast the freight on board (FoB) value for gonggong exports in Batam City using a discrete-time Markov chain with two states: above and below the moving average. There are several types of moving averages, including simple moving averages and weighted moving averages. An initial analysis will determine the moving averages' type and duration following the Gonggong export FOB data in Batam. The data used is the Gonggong export FoB data for Batam City from January 2020 to November 2023. Based on this data, the transition probability matrix will be calculated based on the number of export transitions below and above the Weighted Moving Average 6 (WMA 6) value. Limiting probability from the Markov chain will be used to predict the long-term FOB value of fishery product exports up to steady-state conditions. It was found that steady-state conditions would be reached after 17 months, with a probability of FOB exports below WMA6 of 55.06% and FOB exports above WMA6 of 44.94%.

Abstract Objectives Hypoxia is a known feature of sickle cell anaemia (SCA) which results from chronic anaemia and recurrent vaso-occlusive crisis (VOC) which can cause tissue ischaemia that leads to an end organ damage. The hallmark of SCA is chronic anaemia and recurrent vaso-occlusive crisis. The aim of this study is to compare the oxygen saturation of sickle cell anaemic individuals with the normal haemoglobin type (Hb AA) control and also to determine the prevalence of hypoxemia among SCA. Results Two-hundred and twenty-two (136 Hb SS and 86 Hb AA) participated in the study. The mean ± SD of age (years), oxygen saturation (%) and pulse rate (bpm) of participants with sickle cell anaemia and Hb AA control were 21.85 ± 3.04 and 22.14 ± 3.18 (t = 0.701, p = 0.436), 95.21 ± 3.02 and 98.07 ± 0.81 (t=-8.598, p

Accurate evaluation of the wind convection heat transfer coefficient (hw) for solar‐based systems is essential, especially for solar desalination systems. Thermal behavior and productivity of solar stills are highly affected by the external heat loss through the glass cover. This paper describes a new experimental approach to estimate the hw on the glass cover of the conventional single‐slope solar distiller (CSS). Indoor experiments have been conducted under steady‐state conditions for a wind speed between 0 and 3 m/s. The hw has been evaluated through an energy balance performed on the distiller's glass cover. The results showed that increasing the wind speed increases the hw (from 5.64 to 31.57 W/m2 K) and enhances the distillation rate (from 5.28 to 7.61 mL/min). A new relationship for the hw was proposed for the CSS and compared with the experimental data available in the literature. The comparison shows that the obtained results are close to the data from solar systems, with a deviation ranging from 27.4% to 37%. However, a significant deviation was obtained with earlier models derived from flat plates (from 29.5% to 59%). [ABSTRACT FROM AUTHOR]

Quantum thermal machines can generate steady-state entanglement by harvesting spontaneous interactions with local environments. However, using minimal resources and control, the entanglement is typically weak. Here, we study entanglement generation in a two-qubit quantum thermal machine in the presence of a continuous feedback protocol. Each qubit is measured continuously and the outcomes are used for real-time feedback to control the local system-environment interactions. We show that there exists an ideal operation regime where the quality of entanglement is significantly improved, to the extent that it can violate standard Bell inequalities and uphold quantum teleportation. In agreement with (Khandelwal et al 2020 New J. Phys. 22 073039), we also find, for ideal operation, that the heat current across the system is proportional to the entanglement concurrence. Finally, we investigate the robustness of entanglement production when the machine operates away from the ideal conditions. [ABSTRACT FROM AUTHOR]

The study of a receptor-ligand system generally relies on the analysis of its doseresponse (or concentration-effect) curve, which quantifies the relation between ligand concentration and the biological effect (or cellular response) induced when binding its specific cell surface receptor. Mathematical models of receptor-ligand systems have been developed to compute a dose-response curve under the assumption that the biological effect is proportional to the number of ligand-bound receptors. Given a dose-response curve, two quantities (or metrics) have been defined to characterize the properties of the ligand-receptor system under consideration: amplitude and potency (or halfmaximal effective concentration, and denoted by EC50). Both the amplitude and the EC50 are key quantities commonly used in pharmaco-dynamic modeling, yet a comprehensive mathematical investigation of the behavior of these two metrics is still outstanding; for a large (and important) family of receptors, called cytokine receptors, we still do not know how amplitude and EC50 depend on receptor copy numbers. Here we make use of algebraic approaches (Gr\"obner basis) to study these metrics for a large class of receptor-ligand models, with a focus on cytokine receptors. In particular, we introduce a method, making use of two motivating examples based on the interleukin-7 (IL-7) receptor, to compute analytic expressions for the amplitude and the EC50. We then extend the method to a wider class of receptor-ligand systems, sequential receptor-ligand systems with extrinsic kinase, and provide some examples. The algebraic methods developed in this paper not only reduce computational costs and numerical errors, but allow us to explicitly identify key molecular parameters and rates which determine the behavior of the dose-response curve. Thus, the proposed methods provide a novel and useful approach to perform model validation, assay design and parameter exploration of receptor-ligand systems. [ABSTRACT FROM AUTHOR]