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It is widely claimed that the second Critique’s argument for the postulate of immortality is relevantly different from the first Critique’s argument for the postulate. It is also widely claimed that after the second Critique, Kant distances himself from its particular version of the argument, and even the postulate altogether. It is the purpose of this article to challenge these claims, arguing instead that (a) there is overwhelming textual evidence showing that Kant did not abandon the postulate; (b) the second Critique does not contain a substantially different argument for the postulate than how it is argued for in the first Critique; and (c) the philosophical objections levied against the second Critique’s argument, including its putative substitution of holiness for virtue, become moot once its argument is better understood.
This paper explores the movement of the New York City Interborough Association of Women Teachers (IAWT) for “equal pay for equal work” in teaching salaries, which it won in 1911. The IAWT’s success sheds light on the possibilities and limits of women teachers advocating for change within a feminized profession. Leading the movement were of a group of women teachers, organizing before woman’s suffrage and in an era of sex-differentiated work and pay, who convinced the city’s public and state’s legislators that they deserved pay equal to what men teachers received. They did so by strategic maneuvering in city and state politics and making equal pay look reasonable. And they did so by narrowly defining their goals and leaning on their identities as women to push a theoretically sex-neutral claim of justice. Their success, though limited, was nonetheless a victory in shifting ideas about women’s societal and professional status in New York City and the state.
Bayesian agents, argues Belot, are orgulous: they believe in inductive success even when guaranteed to fail on a topologically typical collection of data streams. Here we shed light on how pervasive this phenomenon is. We identify several classes of inductive problems for which Bayesian convergence to the truth is topologically typical. However, we also show that, for all sufficiently complex classes, there are inductive problems for which convergence is topologically atypical. Last, we identify specific topologically typical collections of data streams, observing which guarantees convergence to the truth across all problems from certain natural classes of effective inductive problems.
Although the theology of Tradition of the Dominican Yves Congar was highly influential in drafting the Dogmatic Constitution Dei Verbum at the Second Vatican Council, postconciliar debates neglected some of the most original aspects of this theology. This article proposes a retrieval of the notion of Tradition as ‘milieu éducatif’, advanced by the theologian in Tradition and Traditions, as a valuable resource for contemporary discussions on Christian formation. It intends to highlight how Congar connected the theological realities of revelation and its transmission by the Church with the concrete practice of Christian life. This notion is, then, put in conversation with contemporary Christian thinkers who have reflected on the practical aspects of Christian formation, chiefly James K.A. Smith. This dialogue aims to show the relevance of Congar’s notion to current discussions. While the theology of Tradition exposed by the French Dominican can be completed and specified by current proposals, it can also offer a new theological depth to those proposals.
The nature and value of the religious priesthood have often been questioned, including after Vatican II. John Paul II, however, claims that the religious priest ‘reproduces in his life the fullness of the mystery of Christ’. Examining Aquinas’s understanding of Christ’s total self-sacrifice provides a model that explains how. In this article, I present a Christological and Thomistic approach to the question by identifying Christ as a religious priest, highlighting one of Aquinas’s patristic sources (St Gregory the Great) and one of his greatest spiritual interpreters of modern times (Bl Columba Marmion). Because of his grace of headship, Christ contains all the perfections found in his members. The perfection of Christ’s priestly and religious life consists in his total sacrifice of himself to the Father out of love. Christ firmly fixed his will to offer himself from the moment of the Incarnation. By vowing to follow the counsels, religious priests imitate the fixity of Christ’s will to offer himself as a total self-holocaust. This conclusion allows me to propose that Christ is the religious priest, which has several theological and pastoral implications.
Exposure to stress related to the COVID-19 pandemic contributes to psychopathology risk, yet not all children are negatively impacted. The current study examined a parasympathetic biomarker of stress sensitivity, respiratory sinus arrhythmia (RSA), as a moderator of the effects of exposure to pandemic stress on child internalizing and externalizing behaviors in a sample of children experiencing economic marginalization. Three to five years pre-pandemic, when children were preschool-aged, RSA during baseline and a challenging parent-child interaction were collected. Mid-pandemic, between November 2020 and March 2021, children’s exposure to pandemic stress and internalizing and externalizing behaviors were collected. Results demonstrated that children who, pre-pandemic, demonstrated blunted parasympathetic reactivity (i.e., no change in RSA relative to baseline) during the dyadic challenge exhibited elevated risk for externalizing behaviors mid-pandemic. Further, this risk was greatest for children exposed to high and moderate levels of pandemic stress. Consistent with diathesis stress and polyvagal frameworks, these conditional effects suggest that blunted parasympathetic reactivity in response to stress in early childhood may escalate the development of externalizing behaviors following stress exposure at school age.
Port-a-caths are implanted intravascular chest ports that enable venous access. With more port placements performed by interventional radiologists, it is important to discern differences in infection and complication rates between double- and single-lumen ports.
Methods:
We retrospectively reviewed 1,385 port placements over 2 years at the University of Miami. Patients were grouped by single- or double-lumen ports. Data on duration of catheter stay, bloodstream infections, malfunctions, and other complications (fibrin sheath, thrombosis, catheter malposition) were collected. Multivariate Cox regression was performed to identify variables predicting port infection.
Results:
The mean patient age was 58.8 years; the mean BMI was 26.9 kg/m2; and 61.5% of these patients were female. Our search revealed 791 double-lumen ports (57.1%) and 594 single-lumen ports (42.9%). The median follow-up was 668 days (range, 2–1,297). Double-lumen ports were associated with significantly higher rates of bacteremia (2.78% vs 0.84%; P = .02), port malfunction (8.3% vs 2.0%; P < .001), fibrin sheath formation (2.2% vs 0.5%; P < .02), catheter tip malposition (1.0% vs 0; P = .01), and catheter-associated thrombosis (1.4% vs 0; P = .003). Multivariate Cox regression analysis, after adjusting for other variables, showed that double-lumen chest ports had 2.98 times (95% confidence interval, 1.12–7.94) the hazard rate of single-lumen ports for developing bloodstream infection (P = .029).
Conclusions:
Double-lumen chest ports are associated with increased risk for bloodstream infection, malfunction, fibrin sheath formation, catheter tip malposition, and catheter-associated thrombosis. Interventional radiologists may consider placing single-lumen ports if clinically feasible; however, future studies are needed to determine clinical significance. The study limitations included the retrospective study design and the potential loss of patient follow-up.
This paper uses the writings of European teachers and Chinese students at St. Stephen’s Girls’ College in Hong Kong—published in English periodicals of its school magazine and local English newspapers—to examine how the school tactically positioned itself as an educational site for the “useful women of China” during a period in Republican China that was simultaneously defined as a time of “cosmopolitan modernity” and “national rebuilding.” St. Stephen’s brand of usefulness responded to the “New Woman” phenomenon in Republican China, and it was defined through the narrative of science learning and a sense of service. Through its progressive science curriculum and social service branch, the school helped prepare a class of “career women” for China. It was in educating this class that St. Stephen’s, in resonance with the colonial state, envisioned its role in the shaping of modern China.
The understanding of the entrainment mechanism of synthetic jets can help optimise the synthetic jet actuators in engineering applications. It is generally believed that vortex rings or strong velocity fluctuations in the near field of the synthetic jet are responsible for its enhanced entrainment. However, in recent years, it has been found that the enhanced entrainment of the synthetic jet may be caused by the instability or the vortex ring breakdown in the transition region. To shed new light on this issue, synthetic jets with different Reynolds numbers and dimensionless stroke lengths are investigated with time-resolved two-dimensional particle image velocimetry. Based on the analyses of velocity triple-decomposition, Fourier mode decomposition and phase-averaged $\lambda _{ci}D/U_0$ field, the streamwise positions of the vortex ring breakdown are determined for the synthetic jets, and the entrainment coefficient can be divided into three components, i.e. the coherent turbulent kinetic energy production, the random turbulent kinetic energy production and the shape of the velocity profile. It is found that the entrainment coefficient is dominated by the component related to the random turbulent kinetic energy production, and reaches its peak value at the position of vortex ring breakdown. The results obtained in different cases show a strong correlation between vortex ring breakdown and entrainment enhancement. From the perspective of instantaneous snapshot, the mechanism of vortex ring breakdown enhanced entrainment is revealed, that is, vortex ring breakdown enhanced the small-scale vortex near the turbulent/non-turbulent interface, resulting in an increase of enstrophy production, and thus enhanced local entrainment.
It is unclear how much adolescents’ lives were disrupted throughout the COVID-19 pandemic or what risk factors predicted such disruption. To answer these questions, 1,080 adolescents in 9 nations were surveyed 5 times from March 2020 to July 2022. Rates of adolescent COVID-19 life disruption were stable and high. Adolescents who, compared to their peers, lived in nations with higher national COVID-19 death rates, lived in nations with less stringent COVID-19 mitigation strategies, had less confidence in their government’s response to COVID-19, complied at higher rates with COVID-19 control measures, experienced the death of someone they knew due to COVID-19, or experienced more internalizing, externalizing, and smoking problems reported more life disruption due to COVID-19 during part or all of the pandemic. Additionally, when, compared to their typical levels of functioning, adolescents experienced spikes in national death rates, experienced less stringent COVID-19 mitigation measures, experienced less confidence in government response to the COVID-19 pandemic, complied at higher rates with COVID-19 control measures, experienced more internalizing problems, or smoked more at various periods during the pandemic, they also experienced more COVID-19 life disruption. Collectively, these findings provide new insights that policymakers can use to prevent the disruption of adolescents’ lives in future pandemics.
We consider inertial waves propagating in a fluid contained in a non-axisymmetric three-dimensional rotating cavity. We focus on the particular case of a fluid enclosed inside a truncated cone or frustum, which is the volume that lies between two horizontal parallel planes cutting an upright cone. While this geometry has been studied in the past, we generalise it by breaking its axisymmetry and consider the case of a truncated elliptic cone for which the horizontal sections are elliptic instead of circular. The problem is first tackled using ray tracing, where local wave packets are geometrically propagated and reflected within the closed volume without attenuation. We complement these results with a local asymptotic analysis and numerical simulations of the original linear viscous problem. We show that the attractors, well known in two dimensional or axisymmetric domains, can be trapped in a particular plane in three dimensions provided that the axisymmetry of the domain is broken. Contrary to previous examples of attractors in three-dimensional domains, all rays converge towards the same limit cycle regardless of initial conditions, and it is localised in the bulk of the fluid.
Let $\mathbb {F}_q^d$ denote the d-dimensional vector space over the finite field $\mathbb {F}_q$ with q elements. Define for $\alpha = (\alpha _1, \dots , \alpha _d) \in \mathbb {F}_q^d$. Let $k\in \mathbb {N}$, A be a nonempty subset of $\{(i, j): 1 \leq i < j \leq k + 1\}$ and $r\in (\mathbb {F}_q)^2\setminus {0}$, where $(\mathbb {F}_q)^2=\{a^2:a\in \mathbb {F}_q\}$. If $E\subset \mathbb {F}_q^d$, our main result demonstrates that when the size of the set E satisfies $|E| \geq C_k q^{d/2}$, where $C_k$ is a constant depending solely on k, it is possible to find two $(k+1)$-tuples in E such that one of them is dilated by r with respect to the other, but only along $|A|$ edges. To be more precise, we establish the existence of $(x_1, \dots , x_{k+1}) \in E^{k+1}$ and $(y_1, \dots , y_{k+1}) \in E^{k+1}$ such that, for $(i, j) \in A$, we have $\lVert y_i - y_j \rVert = r \lVert x_i - x_j \rVert $, with the conditions that $x_i \neq x_j$ and $y_i \neq y_j$ for $1 \leq i < j \leq k + 1$, provided that $|E| \geq C_k q^{d/2}$ and $r\in (\mathbb {F}_q)^2\setminus \{0\}$. We provide two distinct proofs of this result. The first uses the technique of group actions, a powerful method for addressing such problems, while the second is based on elementary combinatorial reasoning. Additionally, we establish that in dimension 2, the threshold $d/2$ is sharp when $q \equiv 3 \pmod 4$. As a corollary of the main result, by varying the underlying set A, we determine thresholds for the existence of dilated k-cycles, k-paths and k-stars (where $k \geq 3$) with a dilation ratio of $r\in (\mathbb {F}_q)^2\setminus \{0\}$. These results improve and generalise the findings of Xie and Ge [‘Some results on similar configurations in subsets of $\mathbb {F}_q^d$’, Finite Fields Appl.91 (2023), Article no. 102252, 20 pages].
Direct numerical simulations are conducted for temporally evolving stratified wake flows at Reynolds numbers from $10\,000$ to $50\,000$ and Froude numbers from $2$ to 50. Unlike previous studies that obtained statistics from a single realization, we take ensemble averages among 80–100 realizations. Our analysis shows that data from one realization incur large convergence errors. These errors reduce quickly as the number of statistical samples increases, with the benefit of ensemble average diminishing beyond 40–60 realizations. The data with ensemble average allow us to test the previously established scalings and arrive at new scaling estimates. Specifically, the data do not support power-law scaling in the centreline velocity deficit $U_0$ beyond the near wake. Its decay rate increases continuously from 0.1 at the onset of the non-equilibrium regime until the end of our calculations without reaching any asymptote. Additionally, while no power-law scalings could be found in the wake width ($L_H$) and wake height ($L_V$) in the late wake, $L_H\sim (Nt)^{1/3}$ is a good working approximation of the wake's horizontal size, where $N$ is buoyancy frequency and $t$ is time. Besides the low-order statistics, we also report the transverse integrated terms and the vertically integrated terms in the turbulent kinetic energy budget equation as a function of the vertical and transverse coordinates. The data indicate that there are two peaks in the vertically integrated production and transport terms, and one peak when the two terms are integrated horizontally.
We prove Abelian and Tauberian theorems for regularized Cauchy transforms of positive Borel measures on the real line whose distribution functions grow at most polynomially at infinity. In particular, we relate the asymptotics of the distribution functions to the asymptotics of the regularized Cauchy transform.
Experimental and theoretical studies on millimetre-sized droplets suggest that at low Reynolds number the difference between the drag force on a circulating water droplet and that on a rigid sphere is very small (less than 1 %) (LeClair et al., J. Atmos. Sci., vol. 29, 1972, pp. 728–740). While the drag force on a spherical liquid droplet at high viscosity ratios (of the liquid to the gas), is approximately the same as that on a rigid sphere of the same size, the other quantities of interest (e.g. the temperature) in the case of a rarefied gas flow over a liquid droplet differ from the same quantities in the case of a rarefied gas flow over a rigid sphere. The goal of this article is to study the effects of internal motion within a spherical microdroplet/nanodroplet – such that its diameter is comparable to the mean free path of the surrounding gas – on the drag force and its overall dynamics. To this end, the problem of a slow rarefied gas flowing over an incompressible liquid droplet is investigated analytically by considering the internal motion of the liquid inside the droplet and also by accounting for kinetic effects in the gas. Detailed results for different values of the Knudsen number, the ratio of the thermal conductivities and the ratio of viscosities are presented for the pressure and temperature profiles inside and outside the liquid droplet. The results for the drag force obtained in the present work are in good agreement with the theoretical and experimental results existing in the literature.
The loading and unloading operations of smart logistic application robots depend largely on their perception system. However, there is a paucity of study on the evaluation of Lidar maps and their SLAM algorithms in complex environment navigation system. In the proposed work, the Lidar information is finetuned using binary occupancy grid approach and implemented Improved Self-Adaptive Learning Particle Swarm Optimization (ISALPSO) algorithm for path prediction. The approach makes use of 2D Lidar mapping to determine the most efficient route for a mobile robot in logistical applications. The Hector SLAM method is used in the Robot Operating System (ROS) platform to implement mobile robot real-time location and map building, which is subsequently transformed into a binary occupancy grid. To show the path navigation findings of the proposed methodologies, a navigational model has been created in the MATLAB 2D virtual environment using 2D Lidar mapping point data. The ISALPSO algorithm adapts its parameters inertia weight, acceleration coefficients, learning coefficients, mutation factor, and swarm size, based on the performance of the generated path. In comparison to the other five PSO variants, the ISALPSO algorithm has a considerably shorter path, a quick convergence rate, and requires less time to compute the distance between the locations of transporting and unloading environments, based on the simulation results that was generated and its validation using a 2D Lidar environment. The efficiency and effectiveness of path planning for mobile robots in logistic applications are validated using Quanser hardware interfaced with 2D Lidar and operated in environment 3 using proposed algorithm for production of optimal path.