Filling the gap. Human cranial remains from Gombore II (Melka Kunture, Ethiopia; ca. 850 ka) and the origin of Homo heidelbergensis

African archaic humans dated to around 1,0 Ma share morphological affinities with Homo ergaster and appear distinct in cranio-dental morphology from those of the Middle Pleistocene that are referred to Homo heidelbergensis. This observation suggests a taxonomic and phylogenetic discontinuity in Africa that ranges across the Matuyama/Brunhes reversal (780 ka). Yet, the fossil record between roughly 900 and 600 ka is notoriously poor. In this context, the Early Stone Age site of Gombore II, in the Melka Kunture formation (Upper Awash, Ethiopia), provides a privileged case-study. In the Acheulean layer of Gombore II, somewhat more recent than 875±10 ka, two large cranial fragments were discovered in 1973 and 1975 respectively: a partial left parietal (Melka Kunture 1) and a right portion of the frontal bone (Melka Kunture 2), which probably belonged to the same cranium. We present here the first detailed description and computer-assisted reconstruction of the morphology of the cranial vault pertaining to these fossil fragments. Our analysis suggest that the human fossil specimen from Gombore II fills a phenetic gap between Homo ergaster and Homo heidelbergensis. This appears in agreement with the chronology of such a partial cranial vault, which therefore represents at present one of the best available candidates (if any) for the origin of Homo heidelbergensis in Africa

Caratterizzazione morfo-dinamica della regione occipitale del cranio nel genere Homo: Una prospettiva evo-devo

The PhD project is based on 3D geometric morphometrics analysis (GMM) of the rear portion of the human cranium (the area surrounding the posterior fossa) in fossil and recent samples. The aim is not simply to quantify the differences in occipital morphology between human species and lineages, but also to relate these differences to the phenomenon of encephalization, which should be regarded as the primary determinant for the variability in cranial morphology within the genus Homo, from both the ontogenetic and evolutionary perspectives. With the emergence of the genus Homo at the beginning of the Early Pleistocene, the non-allometric increase of cerebral volumes (encephalization) – and the subsequent development of the cranium along differential growth vectors (mainly antero-posterior directed) – has led to disturbance of the postural equilibrium between the skull and the spine that occurred in the Late Miocene with the transition to bipedalism and its maintenance among the australopithecines. This disturbance resulted in functional responses, both direct and indirect, in terms of increased instability in the patterns of cranial ossification (due to differential brain growth, highlighted by the presence of ontogenetic stress indicators such as sutural ossicles on the rear braincase) and in the increase and rearrangement of the nuchal muscles that supports and rotates the skull on the spine. The increase in muscle masses has lead in many fossil human species (e.g. Homo erectus , Neanderthals) to the occurrence of large insertions and associated bony structures such as tori, ridges and pits. Only with the emergence of our species, in consequence of the achievement of a more globular cranial shape and moving of the nuchal muscles forward and beneath the cerebral and cerebellar volumes, a new and more stable head balance is regained. Within this evolutionary and developmental melieux, the occurrence and distribution of cranial discrete traits known as hypostotic features (interpreted as an expression of "ontogenetic stress") versus hyperostotic feature, are evaluated in various hominin OTUs by multivatiate statistics. Different patterns are observed in the comparison between Middle Pleistocene samples from Africa, Asia and Europe. Using 2block partial least-square analysis, the non-metric variables (discrete traits) are compared to changes in morphology of the cranial vault recorded by 3D geometric morphometrics. These differences appear to be consistent with geographically-distinct trajectories of encephalization. In this framework, the peculiar (i.e., globular) cranial morphology of H. sapiens emerges from the fossil record of late H. heidelbergensis in Africa, which is characterized by a pattern of "ontogenetic stress" affecting the mid-lateral regions of the cranial vault (in relationship with the expansion, elevation and bending of the parietal lobes of the brain). This suggests a sharp structural reorganization in H. sapiens, which minimises the "ontogenetic stress" and allows to recover a morpho-functional balance, combining high degrees of encephalization with a radial distribution of expansion forces that act on the cranial vault. By contrast, in examining the transition in Europe from H. heidelbergensis to H. neanderthalensis, the analysis carried out in this thesis supported the notion that the increased encephalization – involving first the occipital region, and then the biparietal vault – is associated with the maintenance of a plesiomorphic architecture in the cranial (and encephalic) morphology, with increased instability in growth and osteogenetic processes, as shown by the extreme levels of hypostosis recorded among the Neanderthals. The influence of the muscular loading forces acting on the external surface of the squama of the occipital (on the nuchal scale in particular) considered as the most powerful external “constrains” in relationship with the occipital interspecific shape variability, are also considered by finite element analysis (FEA)

Anonymous crypt P2P. A model for a secure and private communication

The aim of this work is to contribute to the modelling of a peer-to-peer protocol in order to fill a lack that still remains in the wide panorama of developed model, i.e. .e. a deterministic anonymous and crypt peer-to-peer communication system. This work considers first the most important model confirmed by the diffusion and the reliability for their purposes, presenting an overview that focuses on the main characteristics. Than an analysis of the requirements is done and two different strategies are analysed, building two models for different anonymity and security levels. The two models are discussed and a communication protocol for a minimal user client interface is described. Finally the scalability problem is discussed

Naturalness consumption and Biodiversity in an Ecoregion of Central Italy

Landscape naturalness and landscape biodiversity are closely connected with ecosystem sustainability. In this study, “naturalness consumption” and “induced biodiversity” created by human interference were evaluated in an ecoregion of Central Italy that represents a meaningful local example of land-use pattern in a Mediterranean environment. A core set of selected indicators and indexes applied to the database produced by GIS was used first to evaluate the landscape naturalness for each phyto-climatic unit and then to calculate the naturalness consumption. Moreover, the landscape biodiversity of each phyto-climate was evaluated, considering the ecomosaic space organization and taking into account the presence of some important ecological structures like ecotones and hedges. In the naturalness analysis, the highest naturalness consumption occurred in phyto-climates with a higher presence of cultivated areas. In the biodiversity analysis, the phyto-climates with a lower naturalness and a higher presence of agricultural land showed higher values of landscape biodiversity in comparison with the other phyto-climatic units. The results suggest that biodiversity in agro-ecosystems can compensate for naturalness consumption in terms of landscape sustainability. Indeed, natural landscapes carry out a conservative role, while more bio-diverse landscapes offer a balance between human requirements and native ecosystem conditions in a frame of co-evolutionary development

Accurate Maximum Power Tracking in Photovoltaic Systems Affected by Partial Shading

A maximum power tracking algorithm exploiting operating point information gained on individual solar panels is presented. The proposed algorithm recognizes the presence of multiple local maxima in the power voltage curve of a shaded solar field and evaluates the coordinated of the absolute maximum. The effectiveness of the proposed approach is evidenced by means of circuit level simulation and experimental results. Experiments evidenced that, in comparison with a standard perturb and observe algorithm, we achieve faster convergence in normal operating conditions (when the solar field is uniformly illuminated) and we accurately locate the absolute maximum power point in partial shading conditions, thus avoiding the convergence on local maxima

Light Has Been Thrown (on Human Origins): a Brief History of Palaeoanthropology, with Notes on the "Punctuated" Origin of Homo Sapiens

“Light will be thrown on the origin of man and his history”: this was the single line that Charles Darwin devoted to human evolution in the Origin of Species (1859). At present, there is a number of extinct species, which we understand  to be related to human evolution, demonstrating that the Darwin’s prediction was correct: light has been thrown, indeed. Moreover, the science of human origin (or palaeoanthropology) appears to be able to shed much light not only on the natural history of humankind, but also on mechanisms and patterns of "evolution" as a general phenomenon. This is of special interest when we focus on data and hypotheses concerning the origin of our own species, Homo sapiens

Detection of a misaligned broken pipe by electromagnetic interaction

The study we are presenting concerns electromagnetic scattering of a plane wave due to the presence of a misaligned broken pipe buried in a half-space occupied by cement and by asphalt/ground, for civil-engineering applications

Using Beerkan experiments to estimate hydraulic conductivity of a crusted loamy soil in a Mediterranean vineyard

In bare soils of semi-arid areas, surface crusting is a rather common phenomenon due to the impact of raindrops. Water infiltration measurements under ponding conditions are becoming largely applied techniques for an approximate characterization of crusted soils. In this study, the impact of crusting on soil hydraulic conductivity was assessed in a Mediterranean vineyard (western Sicily, Italy) under conventional tillage. The BEST (Beerkan Estimation of Soil Transfer parameters) algorithm was applied to the infiltration data to obtain the hydraulic conductivity of crusted and uncrusted soils. Soil hydraulic conductivity was found to vary during the year and also spatially (i.e., rows vs. inter-rows) due to crusting, tillage and vegetation cover. A 55 mm rainfall event resulted in a decrease of the saturated soil hydraulic conductivity, Ks, by a factor of 1.6 in the inter-row areas, due to the formation of a crusted layer at the surface. The same rainfall event did not determine a Ks reduction in the row areas (i.e., Ks decreased by a non-significant factor of 1.05) because the vegetation cover intercepted the raindrops and therefore prevented alteration of the soil surface. The developed ring insertion methodology on crusted soil, implying pre-moistening through the periphery of the sampled surface, together with the very small insertion depth of the ring (0.01 m), prevented visible fractures. Consequently, Beerkan tests carried out along and between the vine-rows and data analysis by the BEST algorithm allowed to assess crusting-dependent reductions in hydraulic conductivity with extemporaneous measurements alone. The reliability of the tested technique was also confirmed by the results of the numerical simulation of the infiltration process in a crusted soil. Testing the Beerkan infiltration run in other crusted soils and establishing comparisons with other experimental methodologies appear advisable to increase confidence on the reliability of the method that seems suitable for simple characterization of crusted soils

Measuring the shape. Performance evaluation of a photogrammetry improvement applied to the Neanderthal skull Saccopastore 1

Several digital technologies are nowadays developed and applied to the study of the human fossil record. Here, we present a low-cost hardware implementation of the digital acquisition via photogrammetry, applied to a specimen of paleoanthropological interest: the Neanderthal skull Saccopastore 1. Such implementation has the purpose to semi-automatize the procedures of digital acquisition, by the introduction of an automatically rotating platform users can easily build on their own with minimum costs. We provide all the technical specifications, mostly based on the Arduino UNO™ microcontroller technology, and evaluate the performance and the resolution of the acquisition by comparing it with the CT-scan of the same specimen through the calculation of their shape differences. In our opinion, the replication of the automatic rotating platform, described in this work, may contribute to the improvement of the digital acquisition processes and may represent, in addition, a useful and affordable tool for both research and dissemination