Completeness of algebraic CPS simulations

The algebraic lambda calculus and the linear algebraic lambda calculus are two extensions of the classical lambda calculus with linear combinations of terms. They arise independently in distinct contexts: the former is a fragment of the differential lambda calculus, the latter is a candidate lambda calculus for quantum computation. They differ in the handling of application arguments and algebraic rules. The two languages can simulate each other using an algebraic extension of the well-known call-by-value and call-by-name CPS translations. These simulations are sound, in that they preserve reductions. In this paper, we prove that the simulations are actually complete, strengthening the connection between the two languages.Comment: In Proceedings DCM 2011, arXiv:1207.682

Semantics of a Typed Algebraic Lambda-Calculus

Algebraic lambda-calculi have been studied in various ways, but their semantics remain mostly untouched. In this paper we propose a semantic analysis of a general simply-typed lambda-calculus endowed with a structure of vector space. We sketch the relation with two established vectorial lambda-calculi. Then we study the problems arising from the addition of a fixed point combinator and how to modify the equational theory to solve them. We sketch an algebraic vectorial PCF and its possible denotational interpretations

An overview of Alpine and Mediterranean palaeogeography, terrestrial ecosystems and climate history during MIS 3 with focus on the Middle to Upper Palaeolithic transition

This paper summarizes the current state of knowledge about the millennial scale climate variability characterizing Marine Isotope Stage 3 (MIS 3) in S-Europe and the Mediterranean area and its effects on terrestrial ecosystems. The sequence of Dansgaard-Oeschger events, as recorded by Greenland ice cores and recognizable in isotope profiles from speleothems and high-resolution palaeoecological records, led to dramatic variations in glacier extent and sea level configuration with major impacts on the physiography and vegetation patterns, both latitudinally and altitudinally. The recurrent succession of (open) woodlands, including temperate taxa, and grasslands with xerophytic elements, have been tentatively correlated to GIs in Greenland ice cores. Concerning colder phases, the Greenland Stadials (GSs) related to Heinrich events (HEs) appear to have a more pronounced effect than other GSs on woodland withdrawal and xerophytes expansion. Notably, GS 9-HE4 phase corresponds to the most severe reduction of tree cover in a number of Mediterranean records. On a long-term scale, a reduction/opening of forests throughout MIS 3 started from Greenland Interstadials (GIs) 14/13 (ca. 55\u201348 ka), which show a maximum in woodland density. At that time, natural environments were favourable for Anatomically Modern Humans (AMHs) to migrate from Africa into Europe as documented by industries associated with modern hominin remains in the Levant. Afterwards, a variety of early Upper Palaeolithic cultures emerged (e.g., Uluzzian and Proto-Aurignacian). In this chronostratigraphic framework, attention is paid to the Campanian Ignimbrite tephra marker, as a pivotal tool for deciphering and correlating several temporal-spatial issues crucial for understanding the interaction between AMHs and Neandertals at the time of the Middle to Upper Palaeolithic transition

Integrated multidisciplinary ecological analysis from the Uluzzian settlement at the Uluzzo C Rock Shelter, south-eastern Italy

open20siThe Middle to Upper Palaeolithic transition, between 50 000 and 40 000 years ago, is a period of important ecological and cultural changes. In this framework, the Rock Shelter of Uluzzo C (Apulia, southern Italy) represents an important site due to Late Mousterian and Uluzzian evidence preserved in its stratigraphic sequence. Here, we present the results of a multidisciplinary analysis performed on the materials collected between 2016 and 2018 from the Uluzzian stratigraphic units (SUs) 3, 15 and 17. The analysis involved lithic technology, use-wear, zooarchaeology, ancient DNA of sediments and palaeoproteomics, completed by quartz single-grain optically stimulated luminescence dating of the cave sediments. The lithic assemblage is characterized by a volumetric production and a debitage with no or little management of the convexities (by using the bipolar technique), with the objective to produce bladelets and flakelets. The zooarchaeological study found evidence of butchery activity and of the possible exploitation of marine resources, while drawing a picture of a patchy landscape, composed of open forests and dry open environments surrounding the shelter. Ancient mitochondrial DNA from two mammalian taxa were recovered from the sediments. Preliminary zooarchaeology by mass spectrometry results are consistent with ancient DNA and zooarchaeological taxonomic information, while further palaeoproteomics investigations are ongoing. Our new data from the re-discovery of the Uluzzo C Rock Shelter represent an important contribution to better understand the meaning of the Uluzzian in the context of the Middle/Upper Palaeolithic transition in south-eastern Italy.First published: 13 July 2021openSARA SILVESTRINI, MATTEO ROMANDINI, GIULIA MARCIANI, SIMONA ARRIGHI, LISA CARRERA, ANDREA FIORINI, JUAN MANUEL LÓPEZ-GARCÍA, FEDERICO LUGLI, FILOMENA RANALDO, VIVIANE SLON, LAURA TASSONI, OWEN ALEXANDER HIGGINS, EUGENIO BORTOLINI, ANTONIO CURCI, MATTHIAS MEYER, MICHAEL CHRISTIAN MEYER, GREGORIO OXILIA, ANDREA ZERBONI, STEFANO BENAZZI, SPINAPOLICE ENZA ELENASARA SILVESTRINI, MATTEO ROMANDINI, GIULIA MARCIANI, SIMONA ARRIGHI, LISA CARRERA, ANDREA FIORINI, JUAN MANUEL LÓPEZ-GARCÍA, FEDERICO LUGLI, FILOMENA RANALDO, VIVIANE SLON, LAURA TASSONI, OWEN ALEXANDER HIGGINS, EUGENIO BORTOLINI, ANTONIO CURCI, MATTHIAS MEYER, MICHAEL CHRISTIAN MEYER, GREGORIO OXILIA, ANDREA ZERBONI, STEFANO BENAZZI, SPINAPOLICE ENZA ELEN

Backdating systematic shell ornament making in Europe to 45,000 years ago.

Personal ornaments are commonly linked to the emergence of symbolic behavior. Although their presence in Africa dates back to the Middle Stone Age, evidence of ornament manufacturing in Eurasia are sporadically observed in Middle Palaeolithic contexts, and until now, large-scale diffusion has been well documented only since the Upper Palaeolithic. Nevertheless, little is known during the period between ca. 50,000 and 40,000 years ago (ka), when modern humans colonized Eurasia replacing existing hominin populations such as the Neandertals, and a variety of “transitional” and/or early Upper Palaeolithic cultures emerged. Here, we present shell ornaments from the Uluzzian site of Grotta del Cavallo in Italy, southern Europe. Our results show evidence of a local production of shell beads for ornamental purposes as well as a trend toward higher homogeneity in tusk bead shape and size over time. The temporal interval of the layers of interest (45–40 ka) makes Cavallo the earliest known shell ornament making context in Europe

Human talar ontogeny: Insights from morphological and trabecular changes during postnatal growth

The study of the development of human bipedalism can provide a unique perspective on the evolution of morphology and behavior across species. To generate new knowledge of these mechanisms, we analyze changes in both internal and external morphology of the growing human talus in a sample of modern human juveniles using an innovative approach. The sample consists of high‐resolution microCT scans of 70 modern juvenile tali, aged between 8 postnatal weeks and 10 years old, from a broad chronological range from Middle/Late Neolithic, that is, between 4800 and 4500 BCE, to the 20th century. We applied geometric morphometric and whole‐bone trabecular analysis (bone volume fraction, degree of anisotropy, trabecular number, thickness, and spacing) to all specimens to identify changes in the external and internal morphology during growth. Morphometric maps were also generated. During the first year of life, the talus has an immature and globular shape, with a dense, compact, and rather isotropic trabecular architecture, with numerous trabeculae packed closely together. This pattern changes while children acquire a more mature gait, and the talus tends to have a lower bone volume fraction, a higher anisotropy, and a more mature shape. The changes in talar internal and external morphologies reflect the different loading patterns experienced during growth, gradually shifting from an “unspecialized” morphology to a more complex one, following the development of bipedal gait. Our research shows that talar plasticity, even though genetically driven, may show mechanical influences and contribute to tracking the main locomotor milestones

Early life of Neanderthals

The early onset of weaning in modern humans has been linked to the high nutritional demand of brain development that is intimately connected with infant physiology and growth rate. In Neanderthals, ontogenetic patterns in early life are still debated, with some studies suggesting an accelerated development and others indicating only subtle differences to modern humans. Here we report the onset of weaning and rates of enamel growth using an unprecedented sample set of three late (~70-50 ka) Neanderthals and one Upper Paleolithic modern human from Northeastern-Italy via spatially-resolved chemical/isotopic analyses and histomorphometry of deciduous teeth. Our results reveal that the modern human nursing strategy, with onset of weaning at 5-6 months, was present among these Neanderthals. This evidence, combined with dental development akin to modern humans, highlights their similar metabolic constraints during early life and excludes late weaning as a factor contributing to Neanderthals' demise

Insulin dynamics in young women with polycystic ovary syndrome and normal glucose tolerance across categories of body mass index.

BACKGROUND: Evidence favours insulin resistance and compensatory hyperinsulinemia as the predominant, perhaps primary, defects in polycystic ovary syndrome (PCOS). The aim of the present study was to evaluate insulin metabolism in young women with PCOS but normal glucose tolerance as compared with age, body mass index and insulin resistance-matched controls to answer the question whether women with PCOS hypersecrete insulin in comparison to appropriately insulin resistance-matched controls. RESEARCH DESIGN AND METHODS: Sixty-nine cases were divided according to their body mass index (BMI) in normal-weight (N = 29), overweight (N = 24) and obese patients (N = 16). Controls were 479 healthy women (age 16-49 y). Whole body Insulin Sensitivity (WBISI), fasting, and total insulin secretion were estimated following an oral glucose tolerance test (C-peptide deconvolution method). RESULTS: Across classes of BMI, PCOS patients had greater insulin resistance than matched controls (p<0.0001 for all the comparisons), but they showed higher fasting and total insulin secretion than their age, BMI and insulin resistance-matched peers (p<0.0001 for all the comparisons). CONCLUSION: Women with PCOS show higher insulin resistance but also larger insulin secretion to maintain normal glucose homeostasis than age-, BMI- and insulin resistance-matched controls