Radiocarbon (14C) dating is a powerful tool for establishing reliable chronologies for proxy records recovered from environmental archives, including lacustrine sediments. However, lacustrine sediments are often limited with respect to availability of material such as terrestrial macrofossils that are traditionally targeted for 14C dating. Flow cytometry, in combination with physicochemical preprocessing, is an emerging technique for the isolation of pollen from terrestrial sediments, holding the promise of pollen recovery of sufficient purity and efficiency for routine 14C analysis. Here, we examine the performance of this approach by undertaking a comprehensive blank assessment for a new pollen isolation protocol and comparing pollen-14C data against established chronologies for two lake records. Our procedure yields consistent values for constant contamination with extraneous carbon of 1.34±0.40 µg C and an F14C of 0.85±0.04, rendering our method suitable for microscale 14C analysis. The pollen-14C data are largely in agreement with age estimates for the same layers of the lake sediment cores based on macrofossil-14C analysis and tephrochronology. However, we also observe that our pollen samples appear to be, on average, slightly older than their macrofossil counterparts. We hypothesize this to be the result of sedimentary and translocation processes that retard pollen transport and lacustrine deposition.

En este trabajo presentamos los resultados del análisis traceológico de una muestra cerámica procedente de sitios arqueológicos del sector meridional del valle de Abaucán (Tinogasta, Catamarca, Argentina), con el objetivo de visualizar cadenas operativas de los procesos de modelado durante el primer milenio de la era. Para ello la muestra seleccionada, de contextos arqueológicos y relevamientos de piezas de museos, fue sometida al análisis de traza a través de la propuesta de García Roselló y Calvo Trías (2013). Adicionalmente, nos valimos de la experimentación como método de estudio para observar el proceso de manufactura de forma directa y obtener un parámetro controlado que permita la comparación con el material arqueológico. Los resultados brindaron datos con un alto grado de detalle del levantado de las piezas, relacionando las trazas con elecciones técnicas específicas, con herramientas y gestos manuales aplicados por los alfareros en el pasado del oeste de Catamarca.

This thesis presents my contributions to various aspects of the theory of universally Baire sets. One of these aspects is the smallest inner model containing all reals whose all sets of reals are universally Baire (viz., $L(\mathbb {R})$) and its relation to its inner model $\mathsf {HOD}$. We verify here that $\mathsf {HOD}^{L(\mathbb {R})}$ enjoys a form of local definability inside $L(\mathbb {R})$, further justifying its characterization as a “core model” in $L(\mathbb {R})$. We then study a “bottom-up” construction of more complicated universally Baire sets (more generally, determined sets). This construction allows us to give an “L-like” description of the minimum model of $\mathsf {AD}_{\mathbb {R}} + \mathsf {Cof}(\Theta ) = \Theta $. A consequence of this description is that this minimum model is contained in the Chang-plus model. Our construction, together with Woodin’s work on the Chang-plus model, shows that a proper class of Woodin cardinals which are limits of Woodin cardinals implies the existence of a hod mouse with a measurable limit of Woodin cardinals whose strategy is universally Baire.

Another aspect of the theory of universally Baire sets is the generic absoluteness and maximality associated with them. We include some results concerning generic $\Sigma _1^{H(\omega _2)}$-absoluteness with universally Baire sets as predicates or parameters, as well as generic $\Pi _2^{H(\omega _2)}$-maximality with universally Baire sets as predicates. In the second case, we are led to consider the general question of when a model of an infinitary propositional formula can be added by a stationary-set-preserving poset. We characterize when this happens in terms of a game which is a variant of the Model Existence Game. We then give a sufficient condition for this in terms of generic embeddings.

Abstract taken directly from the thesis

E-mail: obrad@math.ucla.edu

URL: https://hal.science/view/index/docid/5273407

We report new AMS radiocarbon dates of 16 samples from the Holocene deposits of the Vistula Spit, a large coastal barrier landform on the Southern Baltic coast. Collection of the samples was conducted directly from the sedimentary succession excavated during 2020–2022 construction of the Vistula Spit shipping canal. The dated material represents several paleosol horizons and peat lenses buried in the dune deposits, as well as their substrate – beach and shallow marine deposits.

Adam Smith seeks to explain in the Wealth of Nations and Lectures on Jurisprudence the persistence of slavery as an institution. In order to accomplish this, he also draws on arguments he had developed in The Theory of Moral Sentiments. The result is a sophisticated explanation that bridges economic, psychological, and moral considerations. After presenting Smith’s explanation, I will consider a discussion of the moral wrong of slavery in the work of Ottobah Cugoano, author of the incisive criticism of the slave trade Thoughts and Sentiments on the Evil of Slavery. I will suggest that Cugoano’s account of what is morally wrong in slavery shows an important lacuna in Smith’s views.

This special issue, “On Their Own Terms: Experts in Imperial China,” examines various kinds of expertise from Han times into the twentieth century from the angle of practitioners themselves, and sometimes even on their own terms.

Paul Erdős and R. Daniel Mauldin asked a series of questions on certain types of polygons of area $1$, the vertices of which can be found in every planar set of infinite Lebesgue measure. We address two of these questions, one on cyclic quadrilaterals and the other on convex polygons with congruent sides, with, respectively, positive and negative answers.

When two black male directors produce university productions of Jackie Sibblies Drury’s Fairview in different parts of the country at the same time, they bond over their shared understanding of the white gaze, and how black people are created and viewed in the white imagination, both in the play and in their own lives.

A range of sizes of eight sea urchin species in the Family Echinometridae (Echinostrephus aciculatus, Heliocidaris erythrogramma, Colobocentrotus atratus, Heterocentrotus mamillatus, Heterocentrotus trigonarius, Echinometra mathaei, Echinometra lucunter, and Echinometra vanbrunti) were digitized and their shapes decomposed using elliptical Fourier analysis to quantify shape differences. Coefficients of sines and cosines of harmonics were used in a principal components analysis to show the separation of species. The principal component analysis shows the Echinometridae shape morphospace with the greatest separation of Echinostrephus and Colobocentrotus from other species. Major loadings were related to morphological measurements: height/diameter, lift of the oral surface above the substrate, and position of the ambitus to height. All species showed an increase in height/diameter with size, but only some species showed a correlation of oral lift or position of the ambitus with Fourier coefficients.

Given $p\in[1,\infty)$ and a bounded open set $\Omega\subset\mathbb{R}^d$ with Lipschitz boundary, we study the $\Gamma$-convergence of the weighted fractional seminorm

\begin{equation*}[u]_{s,p,f}^p=\int_{\mathbb{R}^d} \int_{\mathbb{R}^d} \frac{|\tilde u(x)- \tilde u(y)|^p}{\|x-y\|^{d+sp}}\,f(x)\,f(y)\,\mathrm{d} x\,\mathrm{d} y,\end{equation*}

as $s\to1^-$ for $u\in L^p(\Omega)$, where $\tilde u=u$ on $\Omega$ and $\tilde u=0$ on $\mathbb{R}^d\setminus\Omega$. Assuming that $(f_s)_{s\in(0,1)}\subset L^\infty(\mathbb{R}^d;[0,\infty))$ and $f\in\mathrm{Lip}_b(\mathbb{R}^d;(0,\infty))$ are such that $f_s\to f$ in $L^\infty(\mathbb{R}^d)$ as $s\to1^-$, we show that $(1-s)[u]_{s,p,f_s}^p$ $\Gamma$-converges to the Dirichlet $p$-energy weighted by $f^2$. In the case $p=2$, we also prove the convergence of the corresponding gradient flows.