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Insects experience variable temperature conditions in their natural environment, making constant temperature conditions in studies unrealistic. To address this, we investigated the effects of repeated short-term heat stress (STH) and short-term cold stress (STC) conditions on the pre-oviposition, oviposition, and post-oviposition periods, as well as on fecundity and egg viability of the parthenium beetle, Zygogramma bicolorata Pallister (Coleoptera: Chrysomelidae). We found that pre-oviposition periods were shortest under STH conditions and at the optimal temperature and longest under STC conditions. Conversely, oviposition and post-oviposition periods were longest at the optimal temperature. Oviposition periods were shortest under STH, whereas post-oviposition periods were shortest under both STH and STC conditions. Age-specific fecundity trends were triangular, and egg-viability trends were plateau-shaped at all temperatures. Females subjected to STH conditions experienced the highest oviposition peaks early in their adult life. Conversely, lifetime fecundity and longevity were highest at the optimal temperature, whereas egg viability was maximal under STH conditions. Regardless of the temperature they were maintained at, middle-aged females exhibited the highest fecundity and egg viability. Based on these results, despite reducing overall fecundity and longevity, STH conditions enhanced daily oviposition in females, with the peak occurring early in adult life. Additionally, both STH and STC conditions increased percentage egg viability in parthenium beetles.
In Oliveira, Schlomiuk, Travaglini, and Valls, Geometry, integrability and bifurcation diagrams of a family of quadratic differential systems as application of Darboux theory of integrability, Electron. J. Qual. Theory Differ. Equ.45(2021), 1–90, the authors investigate about the integrability of the family QSH (the whole class of non-degenerate planar quadratic systems possessing at least one invariant hyperbola). However, some very difficult cases are left open in Oliveira, Schlomiuk, Travaglini, and Valls, Geometry, integrability and bifurcation diagrams of a family of quadratic differential systems as application of Darboux theory of integrability, Electron. J. Qual. Theory Differ. Equ.45(2021), 1–90, and the main aim of this article is to study the Liouvillian integrability some of the systems that were left behind in Oliveira, Schlomiuk, Travaglini, and Valls, Geometry, integrability and bifurcation diagrams of a family of quadratic differential systems as application of Darboux theory of integrability, Electron. J. Qual. Theory Differ. Equ.45(2021), 1–90.
Early recognition of cardiac involvement and prediction of disease prognosis are essential for the management of inflammatory diseases such as multisystem inflammatory syndrome. This study aimed to investigate the role of Pentraxin-3 levels in identifying cardiac involvement and evaluating disease severity in patients with multisystem inflammatory syndrome.
Methods:
The study included 56 multisystem inflammatory syndrome patients and 26 healthy children as a control group. The multisystem inflammatory syndrome group was divided into those with cardiac involvement (n = 34) and those without (n = 22), as well as those with clinically mild-moderate (n = 30) and severe (n = 26) multisystem inflammatory syndrome. Blood samples for measurement of Pentraxin-3 levels were obtained from all patients before treatment and from the healthy controls.
Results:
In the patient group, the mean age was 8.2 ± 4 years (range: 2–17 years), and the male-to-female ratio was 1.8. In the control group, these values were 9.5 ± 3.7 years (range: 2–16 years) and 1.9, respectively (p > 0.05). Plasma Pentraxin-3 levels were significantly higher in multisystem inflammatory syndrome patients compared to controls (7.1 ± 5 ng/mL vs. 2.9 ± 2.1 ng/mL, p = 0.001). Patients with cardiac involvement had a significantly higher median Pentraxin-3 level than those without (5.8 ng/mL vs. 4.1 ng/mL, p = 0.004). Severe disease was also associated with a higher median Pentraxin-3 level compared to mild-moderate disease (6.1 ng/mL vs. 4.4 ng/mL, p = 0.001). Pentraxin-3 level was negatively correlated with left ventricular ejection fraction and positively correlated with B-type natriuretic peptide, troponin.
Conclusion:
Elevated Pentraxin-3 levels in multisystem inflammatory syndrome patients may help predict the clinical course of the disease and cardiac involvement. However, larger-scale prospective studies are needed to further elucidate this.
This study introduces vector autoregression (VAR) as a linear procedure that can be used for synthesizing turbulence time series over an entire plane, allowing them to be imposed as an efficient turbulent inflow condition in simulations requiring stationary and cross-correlated turbulence time series. VAR is a statistical tool for modelling and prediction of multivariate time series through capturing linear correlations between multiple time series. A Fourier-based proper orthogonal decomposition (POD) is performed on the two-dimensional (2-D) velocity slices from a precursor simulation of a turbulent boundary layer at a momentum thickness-based Reynolds number, $Re_{\theta }=790$. A subset of the most energetic structures in space are then extracted, followed by applying a VAR model to their complex time coefficients. It is observed that VAR models constructed using time coefficients of 5 and 30 most energetic POD modes per wavenumber (corresponding to $66\,\%$ and $97\,\%$ of turbulent kinetic energy, respectively) are able to make accurate predictions of the evolution of the velocity field at $Re_{\theta }=790$ for infinite time. Moreover, the 2-D velocity fields from the POD–VAR when used as a turbulent inflow condition, gave a short development distance when compared with other common inflow methods. Since the VAR model can produce an infinite number of velocity planes in time, this enables reaching statistical stationarity without having to run an extremely long precursor simulation or applying ad hoc methods such as periodic time series.
We improve known estimates for the number of points of bounded height in semigroup orbits of polarized dynamical systems. In particular, we give exact asymptotics for generic semigroups acting on the projective line. The main new ingredient is the Wiener-Ikehara Tauberian theorem, which we use to count functions in semigroups of bounded degree.
The study presents observations on the interaction of double-blade propeller tip vortices with a smooth-wall turbulent boundary layer (TBL). The wall-bounded helicoidal vortices from the propeller modify the velocity profiles and turbulence statistics. The effects of two different tip clearances, $\epsilon = 0.1\delta _0$ and $0.5\delta _0$, at a matched thrust, are explored with particle image velocimetry to understand the dynamics of tip-vortex formation within the logarithmic and wake regions of the boundary layer. The measurements are performed with $\lambda =U_{tip}/U_{\infty }$ in the range 5.3–5.9, and a blade passing frequency ($\,f_{prop}$) of the same order of the boundary-layer time scale ($\,f_{TBL}$). Observations indicate a reduction in the extent of the log region and an enhancement of the wake parameter $\varPi$, mirroring the behaviour seen in TBLs under adverse pressure gradient conditions. Notably, the slipstream most contracted region exhibits a significant reduction in the skin friction coefficient $C_f$ and an amplification of the velocity fluctuation statistics across the entire boundary layer. At a clearance of $\epsilon = 0.1\delta _0$, there is evidence of the formation of paired coherent wall-bounded structures. The presence of the wall decreases the amplitude of both periodic and stochastic fluctuations obtained with a phase-locked triple decomposition. An exception is observed behind the propeller for the stochastic fluctuations of the wall-normal component of the flow, which become amplified as the blades move away from the wall. This leads to the creation of a more intense phase-locked two-point spatial coherence than that observed in fluctuations aligned with the streamwise direction. Furthermore, results reveal that reduced tip clearances lead to higher viscous dissipation and more active energy exchange between the mean flow and organized motions.
This paper contains a method to prove the existence of smooth curves in positive characteristic whose Jacobians have unusual Newton polygons. Using this method, I give a new proof that there exist supersingular curves of genus $4$ in every prime characteristic. More generally, the main result of the paper is that, for every $g \geq 4$ and prime p, every Newton polygon whose p-rank is at least $g-4$ occurs for a smooth curve of genus g in characteristic p. In addition, this method resolves some cases of Oort’s conjecture about Newton polygons of curves.
Prior research on status has focused primarily on the cognitive perspective, exploring the effects of status and offering a limited understanding of the impact of positive status change and its emotional mechanisms. This study draws upon the two-facet model of pride to examine how positive status change influences the behaviors of new status holders. Specifically, we propose that when status differentiation is low, positive status change enhances new status holders' prosocial behavior through their authentic pride, while in cases of high status differentiation, it increases their self-interested behavior through their hubristic pride. To test our hypotheses, we conducted a series of studies, including a laboratory experiment, a scenario experiment, and a time-lagged multilevel and multisource field study. Our multilevel analyses of the data provided strong support for our hypotheses. Our findings shed light on when and why positive status change triggers different behaviors among new status holders, offering important insights into the emotional mechanisms that underlie the effects of status change.
This article examines the role of state-owned firms in economic growth. While some scholars denigrate state firms, most analysts of East Asian development have noted their importance. To date, however, little work has been done on how state firms operate and how they have actually contributed to industrial development and economic growth. Looking closely at postwar Taiwan as a newly industrializing country and the case of Taiwan Machinery Manufacturing Corporation (TMMC), this article argues that state enterprises resolved coordination failures and provided manufacturing capacity to infant industries. Drawing on company archives and state records, I argue that TMMC helped drive growth through the provision of manufacturing machinery, equipment, parts, repairs, and upgrading. By supplying firms with the necessary technology and materials to modernize production and be competitive on the global market, I show how TMMC helped facilitate Taiwan’s economic miracle.
As I read Zhang and Chen's (2024) perspective paper, I was impressed with the authors' flexibility moving into the medical field and the impact of their research. Moreover, I agreed wholeheartedly with their call to learn by working across fields and with their assessment of how differently management and healthcare scholarship is created, disseminated, and used. Yet I was quite stumped by the editor's request that I suggest some ‘urgent and pressing’ issues that might help management scholars achieve the kind of practical relevance of medical researchers.
For a prime p and a rational elliptic curve $E_{/\mathbb {Q}}$, set $K=\mathbb {Q}(E[p])$ to denote the torsion field generated by $E[p]:=\operatorname {ker}\{E\xrightarrow {p} E\}$. The class group $\operatorname {Cl}_K$ is a module over $\operatorname {Gal}(K/\mathbb {Q})$. Given a fixed odd prime number p, we study the average nonvanishing of certain Galois stable quotients of the mod-p class group $\operatorname {Cl}_K/p\operatorname {Cl}_K$. Here, E varies over all rational elliptic curves, ordered according to height. Our results are conditional, since we assume that the p-primary part of the Tate–Shafarevich group is finite. Furthermore, we assume predictions made by Delaunay for the statistical variation of the p-primary parts of Tate–Shafarevich groups. We also prove results in the case when the elliptic curve $E_{/\mathbb {Q}}$ is fixed and the prime p is allowed to vary.
In this article, we give explicit bounds on the Wasserstein and Kolmogorov distances between random variables lying in the first chaos of the Poisson space and the standard normal distribution, using the results of Last et al. (Prob. Theory Relat. Fields165, 2016). Relying on the theory developed by Saulis and Statulevicius in Limit Theorems for Large Deviations (Kluwer, 1991) and on a fine control of the cumulants of the first chaoses, we also derive moderate deviation principles, Bernstein-type concentration inequalities, and normal approximation bounds with Cramér correction terms for the same variables. The aforementioned results are then applied to Poisson shot noise processes and, in particular, to the generalized compound Hawkes point processes (a class of stochastic models, introduced in this paper, which generalizes classical Hawkes processes). This extends the recent results of Hillairet et al. (ALEA19, 2022) and Khabou et al. (J. Theoret. Prob.37, 2024) regarding the normal approximation and those of Zhu (Statist. Prob. Lett.83, 2013) for moderate deviations.
Expert drivers possess the ability to execute high sideslip angle maneuvers, commonly known as drifting, during racing to navigate sharp corners and execute rapid turns. However, existing model-based controllers encounter challenges in handling the highly nonlinear dynamics associated with drifting along general paths. While reinforcement learning-based methods alleviate the reliance on explicit vehicle models, training a policy directly for autonomous drifting remains difficult due to multiple objectives. In this paper, we propose a control framework for autonomous drifting in the general case, based on curriculum reinforcement learning. The framework empowers the vehicle to follow paths with varying curvature at high speeds, while executing drifting maneuvers during sharp corners. Specifically, we consider the vehicle’s dynamics to decompose the overall task and employ curriculum learning to break down the training process into three stages of increasing complexity. Additionally, to enhance the generalization ability of the learned policies, we introduce randomization into sensor observation noise, actuator action noise, and physical parameters. The proposed framework is validated using the CARLA simulator, encompassing various vehicle types and parameters. Experimental results demonstrate the effectiveness and efficiency of our framework in achieving autonomous drifting along general paths. The code is available at https://github.com/BIT-KaiYu/drifting.
Advances in surgical and perioperative care have reduced the need for prolonged mechanical ventilation in children following cardiac surgery.
Aim of the study:
To evaluate the feasibility and assess the clinical outcomes of an early extubation strategy in the operating room for children undergoing congenital heart surgery, including neonates (age < 28 days).
Methods:
This is a retrospective analysis including congenital open-heart surgery cases. We excluded patients who remained open chest postoperatively or patients with severe hemodynamic instability and high inotropic support from the study. Study variables include age, gender, weight, preoperative cardiac diagnosis, preoperative diagnosis of genetic or chromosomal abnormalities, prematurity, preoperative mechanical ventilation (invasive or non-invasive), cardiopulmonary bypass time, circulatory arrest time, postoperative use of inotropes, duration of mechanical ventilation, postoperative respiratory complication, sepsis, bleeding or other complications, paediatric cardiac ICU stay, total hospital stay, incidence of failed extubation, and operative or postoperative mortality.
Results:
This study included 163 patients who underwent congenital open cardiac surgery, out of these studied patients, 118 (72.4%) were extubated in the operating room. In total, 19.6% of studied patients had Down syndrome. Other genetic or chromosomal disorders were present among 8.6% of studied patients. There was a statistically significant difference between operating room extubation group and non-operating room extubation group regarding Risk Adjustment for Congenital Heart Surgery Score classification, postoperative paediatric ICU duration, postoperative hospital length of stay, vasoactive-inotrope score, duration of inotrope, open chest, and mortality.
Conclusion:
Extubation in the operating room after congenital open-heart surgery was successful in most of our patients, even following complex procedures.
Direct numerical simulation is performed for flow separation over a bump in a turbulent channel. Comparisons are made between a smooth bump and one where the lee side is covered with replicas of shark denticles – dermal scales that consist of a slender base (the neck) and a wide top (the crown). As flow over the bump is under an adverse pressure gradient (APG), a reverse pore flow is formed in the porous cavity region underneath the crowns of the denticle array. Remarkable thrust is generated by the reverse pore flow as denticle necks accelerate the fluid passing between them in the upstream direction. Several geometrical features of shark denticles, including some that had not previously been considered hydrodynamically functional, are identified to form the two-layer denticle structure that enables and sustains the reverse pore flow and thrust generation. The reverse pore flow is activated by the APG before massive flow detachment. The results indicate a proactive, on-demand drag reduction mechanism that leverages and transforms the APG into a favourable outcome.
Evidence abounds on the salience of attachment to early development and beyond. In 2018, Adshead distilled the relevance of 20 years of attachment theory to psychiatric practice.2 We argue research funders must move one step further: develop the evidence around perinatal attachment-informed interventions.
We explore the application of the reference map technique, originally developed for Eulerian simulation of solid mechanics, in Lagrangian kinematics of turbulent flows. Unlike traditional methods based on explicit particle tracking, the reference map facilitates the calculation of flow maps and gradients without the need for particles. This is achieved through an Eulerian update of the reference map, which records the take-off positions of fluid particles. This approach is found to be mathematically equivalent to the work of Leung (J. Comput. Phys., vol. 230, issue 9, 2011, pp. 3500–3524), who computed the flow map of simple two-dimensional flows using an Eulerian approach. We discuss important modifications necessary for its first application to complex three-dimensional turbulent flows, including the conservative, low-dissipation update of the flow map and the treatment of periodic boundary conditions. We first demonstrate the accuracy of finite-time Lyapunov exponent (FTLE) calculations based on the reference map against the standard particle-based approach in a two-dimensional Taylor–Green vortex. Then we apply it to turbulent channel flow at $Re_\tau =180$, where Lagrangian coherent structures identified as ridges of the backward-time FTLE are found to bound vortical regions of flow, consistent with Eulerian coherent structures from the $Q$-criterion. The reference map also proves suitable for material surface tracking despite not explicitly tracking particles. This capability can provide valuable insights into the Lagrangian landscape of turbulent momentum transport, complementing Eulerian velocity field analysis. The evolution of initially wall-normal material surfaces in the viscous sublayer, buffer layer and log layer sheds light on the Reynolds stress-generating events from a Lagrangian perspective.