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Because bark and ambrosia beetles fly during their dispersal and host location processes, their flight height is important for assessing their host selection strategy. There is no consensus regarding the height of their dispersal flight in forests, and their method of approaching trees is unclear. This is also the case for Platypus quercivorus (Murayama) (Coleoptera: Platypodinae), which causes Japanese oak wilt by transporting a pathogenic fungus. To clarify the vertical distribution of the flying population of P. quercivorus inside the host tree canopy, interception traps were set up at heights of 1–9 m from the ground near the main trunk of eight host trees, Quercus serrata Thunberg (Fagaceae). Captured beetles were collected between July and October 2022. Hole-boring activities were observed on all trees during the season, and beetles were captured at all heights from 1 to 9 m. Beetle capture probability increased with a decrease in height, and the number of captured beetles increased with a decrease in distance from the main trunk. However, the trap design in this study could not capture individuals coming directly above and must be addressed to elucidate their method of approaching their host plant.
A field K in a ring language $\mathcal {L}$ is finitely undecidable if $\mbox {Cons}(T)$ is undecidable for every nonempty finite $T \subseteq {\mathtt{Th}}(K; \mathcal {L})$. We extend a construction of Ziegler and (among other results) use a first-order classification of Anscombe and Jahnke to prove every NIP henselian nontrivially valued field is finitely undecidable. We conclude (assuming the NIP Fields Conjecture) that every NIP field is finitely undecidable. This work is drawn from the author’s PhD thesis [48, Chapter 3].
In A Treatise of Human Nature, Hume argues that morality pertains primarily to character, and that actions have moral content only to the extent that they signal good or bad character. I formalize his signalling theory of moral/immoral actions using simple game-theoretic models. Conditions exist under which there is a separating equilibrium in which actions do indeed credibly signal character, but conditions also exist in which there is only a pooling or semi-separating equilibrium. A tradeoff is identified between the signalling value of actions, and the consequentialist goal of incentivizing all character types to choose beneficial actions.
While the idea that Beethoven had African ancestry became popular in the 1960s during the Civil Rights struggle in the United States, its conception arose during an earlier moment: the global New Negro movement of the 1920s. Appearing in newspaper columns, music journals, and essays, Black American writings on Beethoven challenged white musicians’ claims to the canon of Bach, Beethoven, and Brahms. This article argues that the project of making Beethoven Black belonged to a greater and more ambitious endeavour to rewrite Western music history. Black musicologists sought to globalize the Western canon, and in so doing, critique its grand narratives. Locating Black musical idioms in eighteenth-century piano sonatas or conducting archival research on Black European figures such as George Bridgetower, their music histories challenged readers to re-examine just who, exactly, had contributed to the project of cultural modernity and on what grounds.
The present work is devoted to the analysis of drop impact on a deep liquid pool, focusing on the high-energy splashing regimes caused by large raindrops at high velocities. Such cases are characterized by short time scales and complex mechanisms, thus they have received very little attention until now. The BASILISK open-source solver is used to perform three-dimensional direct numerical simulations. The capabilities of octree adaptive mesh refinement techniques enable capturing of the small-scale features of the flow, while the volume of fluid approach combined with a balanced-force surface-tension calculation is applied to advect the volume fraction of the liquids and reconstruct the interfaces. The numerical results compare well with experimental visualizations: both the evolution of crown and cavity, the emanation of ligaments, the formation of bubble canopy and the growth of a downward-moving spiral jet that pierces through the cavity bottom, are correctly reproduced. Reliable quantitative agreements are also obtained regarding the time evolution of rim positions, cavity dimensions and droplet distributions through an observation window. Furthermore, simulation gives access to various aspects of the internal flows, which allows us to better explain the observed physical phenomena. Details of the early-time dynamics of bubble ring entrapment and splashing performance, the formation/collapse of bubble canopy and the spreading of drop liquid are discussed. The statistics of droplet size show the bimodal distribution in time, corroborating distinct primary mechanisms of droplet production at different stages.
We establish an equiconsistency between (1) weak indestructibility for all $\kappa +2$-degrees of strength for cardinals $\kappa $ in the presence of a proper class of strong cardinals, and (2) a proper class of cardinals that are strong reflecting strongs. We in fact get weak indestructibility for degrees of strength far beyond $\kappa +2$, well beyond the next inaccessible limit of measurables (of the ground model). One direction is proven using forcing and the other using core model techniques from inner model theory. Additionally, connections between weak indestructibility and the reflection properties associated with Woodin cardinals are discussed. This work is a part of my upcoming thesis [7].
Cognitive representations are typically analyzed in terms of content, vehicle, and format. Although current work on formats appeals to intuitions about external representations, such as words and maps, in this article, we develop a computational view of formats that does not rely on intuitions. In our view, formats are individuated by the computational profiles of vehicles, that is, the set of constraints that fix the computational transformations vehicles can undergo. The resulting picture is strongly pluralistic, makes space for a variety of different formats, and is intimately tied to the computational approach to cognition in cognitive science and artificial intelligence.
It is theoretically known that an isotropic chemically active particle in an unbounded solution undergoes symmetry breaking when the intrinsic Péclet number ${{Pe}}$ exceeds a finite critical value (Michelin et al., Phys. Fluids, vol. 25, 2013, 061701). At that value, a transition takes place from a stationary state to spontaneous motion. In two dimensions, where no stationary state is possible in an unbounded domain, a linear stability analysis in a large bounded domain (Hu et al., Phys. Rev. Lett., vol. 123, 2019, 238004) reveals that the critical ${{Pe}}$ value slowly diminishes as the domain size increases. Motivated by these findings, we here consider an unbounded domain from the outset, addressing the two-dimensional problem of steady self-propulsion with a focus on the limit ${{Pe}}\ll 1$. This singular limit is handled using matched asymptotic expansions, conceptually decomposing the fluid domain into a particle-scale region, where the leading-order solute transport is diffusive, and a remote region, where diffusion and advection are comparable. The expansion parameter is provided by the product of ${{Pe}}$ and $U$, the unknown particle speed (normalised by the standard autophoretic scale). The problem is unconventional in that the scaling of $U$ with ${{Pe}}$ must be determined in the course of the perturbation analysis. The resulting approximation, $U=4\exp ({-2/{Pe}-\gamma _{E}-1})/{{Pe}}$ ($\gamma _{E}$ being the Euler–Mascheroni constant), is in remarkable agreement with the numerical predictions of Hu et al. in the common interval of validity.
We construct reduced-order models of aeroacoustic sources for single and twin subsonic jets ($M_j=0.9$, $Re=3600$), with the goal of accurately recovering the far-field sound over a wide band of frequencies $St=[0.07,1.0]$ and directivity angles $\phi = [30^{\circ },120^{\circ }]$ within a subdecibel level accuracy. These models are realized via combining spatio-temporally coherent spectral proper orthogonal decomposition (SPOD) modes extracted directly from Lighthill's stress tensor, itself calculated using large-eddy simulation (LES). We consider two sets of twin subsonic jets of diameter $D$ each, with spacings of $0.1D$ and $1D$, where the jets merge upstream and downstream of breakdown, respectively. The closely spaced twin jet decays the slowest due to reduced turbulent stresses which are, however, more broadband due to early merging. Such jets show strong shielding in the plane of jets, especially at shallow directivity angles where sound levels may drop below that of the single jet. The farther spaced twin jets have dynamics more akin to the constituent single jet with turbulent fluctuations peaking here at $St=0.34$, but showing very little shielding, with their overall sound pressure level (OASPL) mostly linked to the nature of extra flow structures created during merging. Three-dimensional, energy-ranked, coherent structures for twin jets exhibit rather poor low-rank behaviour, especially at the far-field spectral peak $St=0.14$. At $St \gtrsim 0.3$, the SPOD wavepackets show strong visual coherence, resembling Kelvin–Helmholtz instability modes upstream of breakdown, while at the lower frequencies, there is very little spatial coherence with wavepackets peaking downstream of breakdown. Although the leading SPOD modes radiate poorly, reduced-order models using a subset of them, up to $45$ SPOD modes per frequency, show a remarkable match (within $1$ dB) against the LES-predicted sound over $0.1 \lesssim St \lesssim 0.5$, at all angles investigated. At other frequencies, the closely spaced twin jet shows more error, due to its greater hierarchy of spatio-temporal structures, showing slower convergence at the shallower angles.
Let $W_{\Gamma} $ be the right-angled Coxeter group with defining graph $\Gamma $. We show that the asymptotic dimension of $W_{\Gamma} $ is smaller than or equal to $\mathrm{dim}_{CC}(\Gamma )$, the clique-connected dimension of the graph. We generalize this result to graph products of finite groups.
A long-standing problem in understanding goal-directed systems has been the insufficiency of mechanistic explanations to make sense of them. This article offers a solution to this problem. It begins by observing the limitations of mechanistic decompositions when it comes to understanding physical fields. We argue that introducing the field concept, as it has been developed in field theory, alongside mechanisms is able to provide an account of goal directedness in the sciences.
Maternal depression and anxiety are associated with infant and mother self- and interactive difficulties. Although maternal depression and anxiety usually co-occur, studies taking this comorbidity into account are few. Despite some literature, we lack a detailed understanding of how maternal depressive and anxiety symptoms may be associated with patterns of mother–infant interaction. We examined associations of maternal postpartum depressive and anxiety symptoms with infant and mother self- and interactive patterns by conducting multi-level time-series models in a sample of 56 Turkish mothers and their 4-month infants. Time-series models assessed the temporal dynamics of interaction via infant and mother self- and interactive contingency. Videotaped face-to-face interaction was coded on a 1s time base for infant and mother gaze and facial affect, infant vocal affect, and mother touch. Results indicated that mothers with high depressive symptoms were vulnerable to infants looking away, reacting with negative touch; their infants remained affectively midrange, metaphorically distancing themselves from mothers’ affect. Mothers with high anxiety symptoms were vulnerable to infants becoming facially dampened and mothers reacted with negative facial affect. Altered infant and mother self-contingency patterns were largely opposite for maternal depressive and anxiety symptoms. These patterns describe foundational processes by which maternal postpartum mood is transmitted to the infant and which may affect infant development.
Dewar (2019) argues that removing excess structure via “sophistication” can have explanatory benefits to removing excess structure via “reduction.” In this paper, I argue that a more robust reason to prefer sophisticated theories is that they have representational benefits.
Among advocates and critics of the “extended evolutionary synthesis” (EES), “reciprocal causation” refers to the view that adaptive evolution is a bidirectional phenomenon, whereby organisms and environments impinge on each other through processes of niche construction and natural selection. I argue that reciprocal causation is incompatible with the view that natural selection is a metaphysically emergent causal process. The emergent character of selection places reciprocal causation on the horns of dilemma, and neither horn can rescue it. I conclude that proponents of the EES must abandon the claim that the process of natural selection features in cycles of reciprocal causation.
Left aortic arch with right descending aorta associated with coarctation of the aorta is a rare congenital cardiac anomaly. Conventional aortic arch repair in this condition may cause airway compression by the abnormally coursing descending aorta. We present the case of a neonate with this anomaly who underwent successful descending aortic translocation to prevent postoperative left main bronchial stenosis.
COVID-19 had the potential to dramatically increase public support for welfare. It was a time of apparent increased solidarity, of apparently deserving claimants, and of increasingly widespread exposure to the benefits system. However, there are also reasons to expect the opposite effect: an increase in financial strain fostering austerity and self-interest, and thermostatic responses to increasing welfare generosity. In this paper, we investigate the effects of the pandemic on attitudes towards working-age unemployment benefits in the UK using a unique combination of data sources: (i) temporally fine-grained data on attitudinal change over the course of the pandemic; and (ii) a novel nationally representative survey contrasting attitudes towards pandemic-era and pre-pandemic claimants (including analysis of free-text responses). Our results show that the pandemic prompted little change in UK welfare attitudes. However, we also find that COVID-era unemployment claimants were perceived as substantially more deserving than those claiming prior to the pandemic. This contrast suggests a strong degree of ‘COVID exceptionalism’ – with COVID claimants seen as categorically different from conventional claimants, muting the effect of the pandemic on welfare attitudes overall.
Studies found support for a link between pubertal timing and self-regulation in low-resource environments. This link could potentially explain a link between pubertal timing and early risk behavior. This study builds on this body of research by examining the mediated effect of pubertal timing on sexual activity through self-regulation in 728 adolescents and their families in a group with poor resources and a group with adequate resources. Income-to-Needs (ITN) was measured at age 7.5 to establish two groups (low-ITN and Medium/High-ITN). Pubertal timing was measured at age 10.5, self-regulation was assessed at age 14 and operationalized with effortful control, and sexual activity was assessed at age 16. Structural equation modeling was employed to test the hypothesized model in both groups. The link between pubertal timing and sexual activity mediated by effortful control was only significant in the low-ITN group. Specifically, more advanced pubertal maturity was associated with lower levels of adolescents’ effortful control, which in turn was associated with more sexual activity at age 16. Findings were partially replicated with a drug use index replacing sexual activity. This study shows a different operating link from pubertal timing to effortful control and subsequent risk behavior in resource-poor environments. Implications are discussed.
Standard narratives about physical teleology say its death was a fait accompli of the Scientific Revolution, but the principle of least action (PLA) has been taken to instantiate teleology’s survival into Enlightenment physics. Other scholars claim this PLA-based teleological metaphysics fell to general philosophical attacks on final causes. None of these narratives fully captures the philosophical interest of its demise. It illustrates a metaphysics being refuted because it could not be coherently modeled in mathematics, hence directly through mathematization and not by philosophical argument or empirical test.