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This paper presents a method to design the response threshold (RT) of energy selective surface (ESS) based on series LC circuits (SLC_based_ESS). A simple SLC_based_ESS structure composed of metal strips and PIN diodes is used for demonstration. According to our research, the RT is rarely related to the geometry parameters of unit cells. By contrast, the RT could be designed by introducing auxiliary structures (ASs) to SLC_based_ESS arrays. With the AS, the induced currents on diodes are enhanced and thus RT is greatly reduced. Prototypes are fabricated and measured under different power levels. The results agree well with simulations, proving an effective design of RT by the proposed method.
Recently, we analysed spontaneous symmetry breaking (SSB) of solitons in linearly coupled dual-core waveguides with fractional diffraction and cubic nonlinearity. In a practical context, the system can serve as a model for optical waveguides with the fractional diffraction or Bose–Einstein condensate of particles with Lévy index $\alpha <2$. In an earlier study, the SSB in the fractional coupler was identified as the bifurcation of subcritical type, becoming extremely subcritical in the limit of $\alpha \rightarrow 1$. There, the moving solitons and collisions between them at low speeds were also explored. In the present paper, we present new numerical results for fast solitons demonstrating restoration of symmetry in post-collision dynamics.
We present a closed-form solution to a discounted optimal stopping zero-sum game in a model based on a generalised geometric Brownian motion with coefficients depending on its running maximum and minimum processes. The optimal stopping times forming a Nash equilibrium are shown to be the first times at which the original process hits certain boundaries depending on the running values of the associated maximum and minimum processes. The proof is based on the reduction of the original game to the equivalent coupled free-boundary problem and the solution of the latter problem by means of the smooth-fit and normal-reflection conditions. We show that the optimal stopping boundaries are partially determined as either unique solutions to the appropriate system of arithmetic equations or unique solutions to the appropriate first-order nonlinear ordinary differential equations. The results obtained are related to the valuation of the perpetual lookback game options with floating strikes in the appropriate diffusion-type extension of the Black–Merton–Scholes model.
We study locally constant skew-product maps over full shifts of finite symbols with arbitrary compact metric spaces as fiber spaces. We introduce a new criterion to determine the density of leaves of the strong unstable (and strong stable) foliation, that is, for its minimality. When the fiber space is a circle, we show that both strong foliations are minimal for an open and dense set of robustly transitive skew-products. We provide examples where either one foliation is minimal or neither is minimal. Our approach involves investigating the dynamics of the associated iterated function system (IFS). We establish the asymptotic stability of the phase space of the IFS when it is a strict attractor of the system. We also show that any transitive IFS consisting of circle diffeomorphisms that preserve orientation can be approximated by a robust forward and backward minimal, expanding, and ergodic (with respect to Lebesgue) IFS. Lastly, we provide examples of smooth robustly transitive IFSs where either the forward or the backward minimal fails, or both.
Poisonous birds are rare but on New Guinea, including Indonesia’s easternmost provinces, no less than nine poisonous species, eight pitohuis and one species of ifrita, are found. Pitohuis when handled can cause sneezing with numbness and burning of nasal tissue and nausea in humans. In the bird markets of western Indonesia novelty birds are traded at a premium and overexploitation of popular songbirds leads traders to find replacement species to meet demand. We conducted over 800 surveys in the bird markets of Sumatra, Java, Bali, Lombok, and Sulawesi between 1994 and 2023 and from 2015 onwards we assessed the online trade in pitohuis and Blue-capped Ifrit Ifrita kowaldi. We identified the species, recorded their prices and location, and the date when the birds were offered for sale. We analysed temporal trends, volumes, prices, and geographical origin of the sellers. Between 1994 and 2014 we did not encounter a single pitohui in the Indonesian bird markets. In the following years we recorded 113 pitohuis in 12 bird markets and we recorded 199 pitohuis for sale online; 248 were variable pitohuis and 54 were Hooded Pitohui Pitohui dichrous. No ifritas were recorded. Most pitohuis were recorded in eastern Java and Bali. Prices differed between eastern Java (mean of US$93) and western Java and Bali (US$185), possibly suggesting pitohuis arrive from West Papua in eastern Java and from there make their way to the outer markets. Pitohuis are marketed as “Papuan Straw-headed Bulbuls”; the Straw-headed Bulbul Pycnonotus zeylanicus is a very popular and expensive songbird from Southeast Asia, including western Indonesia, that has become rare both in the wild and in the markets due to overexploitation. Discussions about pitohuis on online forums rarely mention “poisonous” but when it is mentioned traders dismiss this as something not to worry about and they claim it to be dietary-dependent. Poisonous pitohuis are novelty, as well as master, birds in Indonesia, where they are marketed for their song ignoring any negative side-effects of them being poisonous. The trade in novelty species, when detected early, does allow for the authorities to intervene in a timely manner to ensure that this trade does not impede their conservation.
A graph $G$ is $q$-Ramsey for another graph $H$ if in any $q$-edge-colouring of $G$ there is a monochromatic copy of $H$, and the classic Ramsey problem asks for the minimum number of vertices in such a graph. This was broadened in the seminal work of Burr, Erdős, and Lovász to the investigation of other extremal parameters of Ramsey graphs, including the minimum degree.
It is not hard to see that if $G$ is minimally $q$-Ramsey for $H$ we must have $\delta (G) \ge q(\delta (H) - 1) + 1$, and we say that a graph $H$ is $q$-Ramsey simple if this bound can be attained. Grinshpun showed that this is typical of rather sparse graphs, proving that the random graph $G(n,p)$ is almost surely $2$-Ramsey simple when $\frac{\log n}{n} \ll p \ll n^{-2/3}$. In this paper, we explore this question further, asking for which pairs $p = p(n)$ and $q = q(n,p)$ we can expect $G(n,p)$ to be $q$-Ramsey simple.
We first extend Grinshpun’s result by showing that $G(n,p)$ is not just $2$-Ramsey simple, but is in fact $q$-Ramsey simple for any $q = q(n)$, provided $p \ll n^{-1}$ or $\frac{\log n}{n} \ll p \ll n^{-2/3}$. Next, when $p \gg \left ( \frac{\log n}{n} \right )^{1/2}$, we find that $G(n,p)$ is not $q$-Ramsey simple for any $q \ge 2$. Finally, we uncover some interesting behaviour for intermediate edge probabilities. When $n^{-2/3} \ll p \ll n^{-1/2}$, we find that there is some finite threshold $\tilde{q} = \tilde{q}(H)$, depending on the structure of the instance $H \sim G(n,p)$ of the random graph, such that $H$ is $q$-Ramsey simple if and only if $q \le \tilde{q}$. Aside from a couple of logarithmic factors, this resolves the qualitative nature of the Ramsey simplicity of the random graph over the full spectrum of edge probabilities.
This paper presents an analytical mapping of institutional design possibilities for alternative ways for digital platforms to institutionalise property and corporate form. It builds on the institutional imagination catalysed by three vignettes of experimental sharing economy initiatives presented towards the start of the paper, each of which highlights the imbrication and interdependence between economic and social dimensions of the sharing economy. The paper then interrogates the vignettes through three analytical entry points to the institutional design of commons-based sharing economies: platform, care and place. By remapping the vignettes’ practices around these three entry points, the paper shows how they help constitute the incipient formalisation of commons-based approaches to the sharing economy. The prospects for carrying out a redesign of property and corporate forms more generally thereby become more visible, providing a sound foundation for more in-depth empirical and historical work on alternative trajectories of the sharing economy in the future.
Recent technological advancements have facilitated alternative work arrangements. This paper investigates how flextime and working from home (WfH) relate to workers’ well-being using longitudinal data drawn from the Understanding Society study for the UK. It accounts for individual, job, and family characteristics while controlling for individual fixed effects. Additionally, it employs the Oster test to examine the potential influence of unobserved variables. Results show that men experience improved job satisfaction and mental health with flextime arrangements, while women predominantly benefit in terms of job satisfaction. Additionally, women adopting remote work report heightened satisfaction with job and life, and better mental health, whereas men primarily report greater job satisfaction. Interestingly, flextime effects are stronger for men, while WfH is more beneficial for women. Some heterogeneous effects are also found by parental status, age, and income groups.
The invertebrate indices for assessing water quality have not been widely developed in tropical regions where invertebrate diversity is generally high and severe water quality degradation is ongoing. We compared the applicability of six existing invertebrate indices using the dataset from 23 Indonesian streams and developed a new index by modifying an existing one using Threshold Indicator Taxa Analysis (TITAN). Analyses using general linear models (GLMs) revealed that among the six existing indices, the biological monitoring working party (BMWP)-based scoring system for Thailand streams (BMWP THAI) exhibited the strongest negative relationship with phosphate (PO4-P) concentration, a proxy for stream water quality. Based on the results of TITAN, five taxa were added to develop a modified invertebrate index, namely BMWP IDN, by assigning taxon scores in accordance with the responses to the water quality gradient. The relationship between the BMWP IDN and PO4-P concentration was found to be stronger than any of the existing invertebrate indices, indicating the superiority of the new index. Therefore, the extraction of uncovered sensitive taxa was important for modifying the existing index, and this study can contribute to improving the invertebrate index for assessing water quality of Indonesian streams.
Distressing mental images are common in people with psychosis. The central role of metacognitive difficulties in psychosis suggests that metacognitive interventions with imagery properties could play a central role in managing distressing mental imagery. A brief imagery-based metacognitive intervention was developed to target the control mechanism of distressing mental images in psychosis.
Aims:
A fixed baseline case series was designed to investigate whether the intervention was acceptable, feasible and effective.
Method:
Eight participants who met criteria for a schizophrenia spectrum diagnosis and experienced distressing future-oriented mental images took part in the case series, which consisted of three phases; baseline, intervention, and follow-up. Symptoms of anxiety, depression, persecutory delusions and schemas were assessed pre- and post-intervention, and qualitative feedback was collected at follow-up.
Results:
The metacognitive intervention was feasible, acceptable, and rated as highly satisfactory. One participant dropped out at the baseline phase. No adverse events were reported. Positive change scores with a decrease in symptoms were reported for anxiety, depression, persecutory delusions, and schemas. Tau-U analysis showed positive trends and high effect sizes on mental imagery characteristics at follow-up.
Conclusion:
Our findings suggest that it is acceptable and feasible to engage people with psychosis in a brief imagery-based metacognitive intervention and that positive change can be achieved. Further studies are needed to replicate and clarify the findings of our study and develop the evidence base for this intervention.
Aerothermodynamic characteristics of a sphere in a subsonic flow are calculated over a broad range of gas rarefaction by the direct simulation Monte Carlo method based on ab initio interatomic potentials and Cercignani–Lampis surface scattering kernel. Calculations of the drag and average energy transfer coefficients are performed for various noble gases in the range of Mach number from 0.1 to 1. The obtained results point out that the influence of the interatomic potential is weak in subsonic flows. A comparison of the present results with a linear theory shows that the numerical solutions at Mach number equal to 0.1 are close to those obtained from the linearized kinetic equation in the transitional and free-molecular regimes. In the near-continuum flow regime, the difference between the present solution and the linear theory is significant. To reveal the effects of the gas–surface accommodation, a few sets of the tangential momentum and normal energy accommodation coefficients are considered in simulations. It is shown that the effect of the accommodation coefficients on the sphere drag is not trivial, and, for non-diffuse scattering, the drag coefficient can be either larger or smaller than that for diffuse scattering. The effect of the sphere temperature is also investigated and the calculated values of the average energy transfer coefficient are used to find the Stanton number, recovery factor and adiabatic surface temperature. The numerical results for the sphere drag and energy transfer are compared with the semi-empirical fitting equations known from the literature.
Clozapine is the only evidence-based intervention for treatment-resistant schizophrenia. One of the drug's most well-known and potentially fatal adverse effects is agranulocytosis (severe neutropenia). Hence, regular blood tests are an essential component of clozapine treatment. This article presents a narrative review of the history, incidence, potential aetiology and management of clozapine-associated neutropenia. It gives an overview of clozapine monitoring requirements, including those for benign ethnic neutropenia. We point to the growing body of evidence that the risk of clozapine-induced agranulocytosis is mostly confined to the first year of treatment and that the risk of fatality is considerably lower than previously assumed. Given the absence of alternative evidence-based interventions for treatment-resistant schizophrenia, we suggest that rechallenging with clozapine should be considered in most patients with clozapine-associated mild to moderate neutropenia who do not respond to other treatments. A more careful risk–benefit analysis is needed in cases of severe neutropenia (agranulocytosis).
We consider the constrained-degree percolation model in a random environment (CDPRE) on the square lattice. In this model, each vertex v has an independent random constraint $\kappa_v$ which takes the value $j\in \{0,1,2,3\}$ with probability $\rho_j$. The dynamics is as follows: at time $t=0$ all edges are closed; each edge e attempts to open at a random time $U(e)\sim \mathrm{U}(0,1]$, independently of all the other edges. It succeeds if at time U(e) both its end vertices have degrees strictly smaller than their respective constraints. We obtain exponential decay of the radius of the open cluster of the origin at all times when its expected size is finite. Since CDPRE is dominated by Bernoulli percolation, this result is meaningful only if the supremum of all values of t for which the expected size of the open cluster of the origin is finite is larger than $\frac12$. We prove this last fact by showing a sharp phase transition for an intermediate model.
Ventilator-associated pneumonia (VAP) is a well-established cause of morbidity in critically ill patients. Current VAP criteria exclude patients on extracorporeal membrane oxygenation (ECMO). This retrospective analysis tests the validity of VAP in this population, as well as a new proposed diagnostic criterion for ECMO-associated pneumonia.
To evaluate the impact of receptive vocabulary versus years of education on neuropsychological performance of Black and White older adults.
Method:
A community-based prospectively enrolled cohort (n = 1,007; 130 Black, 877 White) in the Emory Healthy Brain Study were administered the NIH Toolbox Picture Vocabulary Test and neuropsychological measures. Group differences were evaluated with age, sex, and education or age, sex, and Toolbox Vocabulary scores as covariates to determine whether performance differences between Black versus White participants were attenuated or eliminated.
Results:
With vocabulary as a covariate, the main effect of race was no longer significant for the MoCA, Phonemic Fluency, Rey Auditory Verbal Learning Test, and Rey Complex Figure Test immediate and delayed recall. Although still significantly different between groups, the effect sizes for Animal Fluency, Trails B-A, Symbol Digit Modalities Test, and Rey Copy were attenuated, with the greatest reductions occurring for the Multilingual Naming Test and Judgment of Line Orientation.
Conclusions:
Findings support the value of using receptive vocabulary as a proxy for premorbid ability level when comparing the cognitive performance of Black and White older adults. The results extend investigations using measures of single word reading to encompass measures assessing word meaning.
To describe the effect of a Stenotrophomonas maltophilia (SM) respiratory culture nudge on antibiotic use in colonized patients.
Design:
IRB-approved quasi-experiment.
Setting:
Five acute-care hospitals in Michigan.
Patients:
Adult patients with SM respiratory culture between 01/01/2022 and 01/27/2023 (pre-nudge) and 03/27/2023–12/31/2023 (post-nudge). Patients with active community/hospital/ventilator-acquired pneumonia or who received SM-targeted antibiotics at the time of culture were excluded.
Methods:
A nudge comment was implemented 02/2023 stating: “S. maltophilia is a frequent colonizer of the respiratory tract. Clinical correlation for infection is required. Colonizers do not require antibiotic treatment.” The primary outcome was no treatment with SM-therapy; secondary outcomes were treatment with SM-therapy ≥72 hrs, length of stay, and in-hospital, all-cause mortality. Safety outcomes included antibiotic-associated adverse drug events (ADEs).
Results:
94 patients were included: 53 (56.4%) pre- and 41 (43.6%) post-nudge. Most patients were men (53, 56.4%), had underlying lung disease (61, 64.8%), and required invasive ventilatory support (70, 74.5%). Eleven (11.7%) patients resided in a long-term care facility. No treatment with SM therapy was observed in 13 (23.1%) pre- versus 32 (78.0%) post-nudge patients (P <0.001). There were no differences in secondary outcomes. Antibiotic-associated ADEs were common (33/41, 76%) in patients who received ≥72hrs of SM-therapy: fluid overload (18, 44%), hyponatremia (17, 42%), elevated SCr (12, 29%), hyperkalemia (5, 12%). After adjustment for confounders, post-nudge was associated with 11-fold increased odds of no treatment with SM-therapy (adjOR, 11.72; 95%CI, 4.18–32.83).
Conclusions:
A targeted SM nudge was associated with a significant reduction in treatment of colonization, with similar patient outcomes. SM-treated patients frequently developed antibiotic-associated ADEs.
Capsules, which are potentially active fluid droplets enclosed in a thin elastic membrane, experience large deformations when placed in suspension. The induced fluid–structure interaction stresses can potentially lead to rupture of the capsule membrane. While numerous experimental studies have focused on the rheological behaviour of capsules until rupture, there remains a gap in understanding the evolution of their mechanical properties and the underlying mechanisms of damage and breakup under flow. We here investigate the damage and rupture of bioartificial microcapsules made of ovalbumin reticulated with terephthaloyl chloride and placed in simple shear flow. We characterize damage by identifying how the surface shear modulus of the capsule membrane changes over time. Rupture is then characterized by comparing the number and size distribution of capsules before and after exposure to shear, while varying the shear rates and time during which capsules are sheared. Our findings reveal how the percentage of ruptured capsules increases with their size, exposure time to shear, and the ratio of viscous to elastic forces at rupture.