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When looking into land use and human agency in the modification of the landscape, the concepts of socio-economic opportunities vs. natural constraints is one of the key issues. In comparison with the modern world, past human communities relied much more upon local resources and a tight societal structure to better adapt to the conditions and changes in the surrounding environment. Therefore, in the study of prehistorical cultures land use is both a strong source of information about sustenance strategies and community behaviours and a subject potentially easier to model within a set of natural and social parameters. To this purpose, we investigated the settlement distribution patterns of Bronze Age structures of the Nuragic culture on the island of Sardinia (Italy) using spatial point pattern analysis. We investigated different covariates divided into natural (topography, water and geological resources) and cultural (type of structure, settlement hierarchy), alone and in combination, and looked at how each could explain the distribution of Nuragic sites.Several covariates from both natural and cultural groups show significant values, with the best representing models of pattern distribution coming from the combination of covariates from both groups. Aside from topographic parameters, distance from known ore deposits seems to have an impact on structure density. Among cultural covariates, there is a clear association between simple and complex megalithic structures (nuraghes). This pattern suggests the collation of smaller structures around larger settlements, either by the former emerging from the presence of the latter or vice versa. These findings offer new insight on the development and ways of life of the Nuragic society in their geographical context, and highlight how the relationship between the physical and the social aspects of human-landscape interactions is fundamentally interdependent. This approach could also represent a potential tool to compare to other Bronze Age and prehistorical communities.

dynamics of a rotating colony and trajectory of cells

In the southwestern coast of Sardinia coastal sediments preserve evidence of geomorphic processes such as slope, colluviation and pedogenesis, as well as human activities. We present the preliminary results of an integrated approach focused on descriptive and analytical soil investigation together with micromorphological data, geoarchaeological investigations and landscape survey as part of a larger project aimed to characterise the geoheritage of the region. We describe palaeosol sequences related to stratal architectures that date back to the Late Pleistocene. Our goal is to gain information on landscape evolution in the area and the effect of human agency on the larger environment, as well as document hydroclimatic change.At the current coastline level, the last marine transgression exposed marine sequences dated to the MIS5, later covered by fluvial and slope deposits throughout the last portion of the Late Quaternary. Several soil sequences show traces of recent colluvial events of anthropogenic origin. Such deposits contain pottery and other human made materials related to the Iron/roman age. These initial findings seem to suggest a strong control of human activity on environmental change in the area, not related to a single location but widespread in the landscape. This control was such to cover and take precedence over the natural pre-existing surface dynamics, thereby complicating the definition of Anthropocene in Sardinia. Further investigations would bring more light on the ways palaeosols can inform on the shifts in human land use and occupation. How has land use accelerated since the Bronze age? How can these palaeosequences inform us about anthropogenic processes overstepping natural ongoing surface dynamics?

The geological substrate and its landforms, as main providers of natural resources, have a clear influence on landscape management practices The landscape evolution of the island of Sardinia (Italy) during the Holocene has strongly influenced the populations settled there, especially during the Bronze Age. We constructed a map of the land units in the southwestern corner of Sardinia and compared them with the distribution of known Bronze Age megalithic towers called nuraghes. Our aim is to understand which factors represent relevant criteria for settlement and try to infer possible causes.The vast majority of nuraghes are located in proximity to river networks at low and mid elevations. Most densely settled areas also show the highest landscape diversity with a variety of land units much higher than the rest of the territory. Another potential factor affecting the location choice for nuraghes is the presence of elevated outcrops, which provide the advantage of a raised position and of stable foundations. The interaction of human dispersal patterns with landscape features can provide useful information on the sustenance strategies of past communities. It can therefore be interesting to consider the combined effect of geodiversity and landscape diversity in order to build more accurate dispersal models.

Coordinated rotational motion is an intriguing, yet still elusive mode of collective cell migration, which is relevant in pathological and morphogenetic processes. Most of the studies on this topic have been carried out on confined epithelial cells. The driver of collective rotation in such conditions has not been clearly elucidated, although it has been speculated that spatial confinement can play an essential role in triggering cell rotation. Here, we study the growth of epithelial cell colonies freely expanding (i.e., with no physical constraints) on the surface of cell culture plates, a case which has received scarce attention in the literature. We find that coordinated cell rotation spontaneously occurs in cell clusters in the free growth regime, thus implying that cell confinement is not necessary to elicit collective rotation as previously suggested. The collective rotation was size and shape dependent: a highly coordinated disk-like rotation was found in small cell clusters with a round shape, while collective rotation was suppressed in large irregular cell clusters generated by merging of different clusters in the course of their growth. The angular motion was persistent in the same direction, although clockwise and anticlockwise rotations were equally likely to occur among different cell clusters. Radial cell velocity was low as compared to the angular velocity. A clear difference in morphology was observed between cells at the periphery and the ones in the core of the clusters, the former being more elongated and spread out as compared to the latter. Overall, our results provide the first quantitative and systematic evidence that coordinated cell rotation does not require a spatial confinement and occurs spontaneously in freely expanding epithelial cell colonies.

This publication is part of the proceedings of the Biot-Bažant Conference on Engineering Mechanics and Physics of Porous Materials, which took place virtually on June 1-3, 2021. It contains a one-page abstract and the video of the talk that was given at the conference.

Environmental and time-scale reconstructions of deep sedimentary sequences are based on a wide variety of markers to highlight and characterise environmental variations within a homogeneous sedimentary setting. Moreover, in the lack of reliable age constrain, it is often the only way to highlight timelines and correlations between sequences collected in different places. Within this set of potential markers, palaeosols developed on terrestrial sedimentary beds during biostasy conditions stand out. These evidences are often useful for both their visibility within a core and their strong environmental implications. In continental basins characterized by glacial contributions, they also represent potential time information linked to the fluctuation of glacial and interglacial periods. However, the interpretation of sedimentary markers in cores using visual identification to the naked eye can possibly lead to the wrong conclusions: this method for palaeosol identification is not straightforward and prone to the production of false positives. We conducted detailed micromorphological investigations on a series of markers in a core from the central-northern portion of the Po Plain foreland basin, proximal to the Southern Italian Alps which fed the basin during the Pleistocene.Seventeen sedimentary anomalies were identified during the visual description on the basis of colours and textures as potential palaeosols and were sampled to be studied in thin section. The study allowed to recognise evidences of soil-forming processes, which could characterise the past pedogenesis as well as their environment. From micromorphological analysis, only 4 samples showed visible signs of pedogenesis or post depositional weathering caused by proximity to the surface. Observed elements range from pedoplasmation to pedogenetic features related to redoximorphic processes and clay illuviation, thus allowing to interpreted them as truncated palaeosols. Conversely, 6 samples showed forms of transport of soil material, either sedimentary or in solution, but did not represent soils formed in situ; these can be interpreted as pedorelicts. Of the remaining samples, 5 were calcrete potentially related to groundwaters, and 2 represented accumulations of Fe/Mn oxides in wetland conditions (“bog iron”). These results suggest a reconsideration of the role of palaeosols as stratigraphic markers in the study of subsurface sedimentary sequences. Precise identification and microstructure characterization are necessary to avoid possible misinterpretations and correlations among cores.

In a world where the interaction between humans and the physical landscape is deep and widespread since prehistory, geological and cultural heritage are still very much separate and addressed by experts and professionals coming from very different fields. The scarcity of effective communication channels impairs shared experience and fruitful collaboration in enhancing geosite awareness in the general public. When integrated approaches appear, they often still concentrate on the cultural narration using geological and environmental information only to support a palimpsest very much human-centred. Attention on integrated divulgation of the geological and natural processes surrounding cultural sites is still lacking. In fact, there is the possibility of walking the opposite path: that is, of using cultural heritage in order to inform the public and divulgate past and current geological processes acting on the wider landscape. This is especially true in highly dynamic environments, where geomorphological processes visibly modify cultural landmarks over time. In this sense, coasts are the ideal setting. They have represented one of the preferential places for human settlement since the dawn of civilization. Coastal environments show strong, complex geomorphological dynamics subject to cycles and variations over time which can be recorded in many different archives, some readily understandable by non-experts.In this contribution we bring examples of how the interaction between cultural heritage and geoheritage can be used to enhance the communication of geomorphological issues. The coastal area of the southwestern portion of Sardinia (Italy) is the location of numerous archaeological settlements, ranging from Mesolithic shelters to wide, majestic Punic and Roman trade ports and cities. Sea level rise since the Last Glacial Maximum has widely interested this territory, and its effect is very well recorded in archaeological contexts. Here, variations in topography and geomorphology are changing the contexts of the sites themselves and sometimes threat their integrity through different geological and geomorphological hazards. The development of narrations focused on explaining these processes, using the archaeological evidence as a tool to convey geological concepts, might raise geological awareness in the general public and spread knowledge about the geomorphological history and features of the local and global landscape.

We study the implications of state dependent costs of policy mismatch in political agency models where politicians have reputational concerns and ``good'' politicians share the same objectives with the voters. We find that state-dependent costs can increase the set of parameters where pandering is an equilibrium strategy. Indeed, in our model, pandering can arise even without office rents. Moreover, we show that voters do not necessarily prefer biased politicians to be in favour of the policy that produces the cheapest expected cost of mismatch. We discuss the implications of those results for populism, environmental policies and the equilibrium incentives to over- or under-provide lockdowns or other mitigation measures.

Malaria is associated with significant microcirculation disorders, especially when the infection reaches its severe stage. This can lead to a range of fatal conditions, from cerebral malaria to multiple organ failure, of not fully understood pathogenesis. It has recently been proposed that a breakdown of the glycocalyx, the carbohydrate-rich layer lining the vascular endothelium, plays a key role in severe malaria (SM), but direct evidence supporting this hypothesis is still lacking. Here, the interactions between Plasmodium falciparum infected red blood cells (PfRBCs) and endothelial glycocalyx are investigated by developing an in vitro, physiologically relevant model of human microcirculation based on microfluidics. Impairment of the glycocalyx is obtained by enzymatic removal of sialic acids residues, which, due to their terminal location and net negative charge, are implicated in the initial interactions with contacting cells. We show a more than twofold increase of PfRBCs adhesion to endothelial cells upon enzymatic treatment, relative to untreated endothelial cells. As a control, no effect of enzymatic treatment on healthy red blood cells adhesion is found. The increased adhesion of PfRBCs is also associated with cell flipping and reduced velocity as compared to the untreated endothelium. Altogether, these results provide a compelling evidence of the increased cytoadherence of PfRBCs to glycocalyx-impaired vascular endothelium, thus supporting the advocated role of glycocalyx disruption in the pathogenesis of this disease.

We study a (possibly repeated) trust game between a principal and an agent, whose skills are private information at the beginning of the relationship and later revealed to the principal. The principal can commit to a long-term relationship through a contract. We show that such a commitment may be needed for trust. Furthermore, the optimal length of the contract between the principal and the agent and the principal’s payoff are not monotonic in both the probability that the agent is high-skilled and the value of replacing a low-skilled agent with a high-skilled one.

Il microdispositivo presentato nel presente brevetto per invenzione industriale consente di realizzare un gradiente controllato di chemoattraente o altra sostanza chimica, al fine di investigare la motilità chemotattica delle cellule in 2D e 3D. Il saggio di chemiotassi viene realizzato mediante osservazione in microscopia Time Lapse in vitro del campione sottoposto ad un gradiente di concentrazione controllato di una specifica sostanza, mantenendo condizioni di temperatura, umidità, concentrazione di CO2 e pH analoghe a quelle fisiologiche.

La cella per la realizzazione di un saggio di Chemiotassi in 2D e 3D consente di osservare mediante tecniche di microscopia Time Lapse in vitro, dei campioni, tipicamente delle cellule in coltura, mentre sono sottoposti a gradienti controllati di concentrazione di una specifica molecola o composto. La cella, divisa in due o più pozzetti, consente di realizzare un flusso noto di chemoattraente nei pozzetti contenenti i campioni in esame. Durante il saggio di chemiotassi la cella contenente i campioni viene mantenuta in condizioni del tutto analoghe a quelle fisiologiche, in termini di temperatura, umidità, concentrazione di CO2 e pH; inoltre la cella consente di mimare la matrice extracellulare da cui le cellule sono tipicamente circondate, sospendendole in un gel 3D di collagene; la cella consenta anche di investigare la capacità delle cellule di invadere tessuti, in presenza o meno di uno stimolo chemotattico. Il saggio consente di monitorare la traiettoria descritta dalle cellule sottoposte allo stimolo chemotattico, tramite tecniche di analisi delle immagini. Dalla analisi delle traiettorie descritte è possibile ricavare informazioni quantitative sulla motilità cellulare in presenza o meno di stimoli chemotattici noti e riproducibili.

Biotechnologies such as high-throughput screening (HTS) enable evaluation of large compound libraries for their biological activity and toxic properties. In the field of drug development, embryonic stem (ES) cells have been instrumental in HTS for testing the effect of new compounds. We report an innovative method in one step to differentiate ES cells in neurons and glial cells. The four different neuronal subtypes, -aminobutyric acid (GABA)-ergic, dopaminergic, serotonergic, and motor neurons, are formed in culture. This protocol is adaptable to small wells and is highly reproducible, as indicated by the Z-factor value. Moreover, by using either leukemia inhibitory factor (LIF) or recombinant Cripto protein in our culture conditions, we provide evidence that this protocol is suitable for testing the effect of different molecules on neuronal differentiation of ES cells. Finally, thanks to the simplicity in carrying out the experiment, this method provides the possibility of following the morphological evolution of the in vitro differentiating neuronal cells by timelapse videomicroscopy. Our experimental system provides a powerful tool for testing the effect of different substances on survival and/or differentiation of neuronal and glial cells in an HTS-based approach. Furthermore, using genetically modified ES cells, it would be possible to screen for drugs that have a therapeutic effect on specific neuronal pathologies or to follow, by time-lapse videomicroscopy, their ability to in vitro differentiate.

La presente invenzione comprende l’electrospinning di soluzioni di esteri dell’acido ialuronico, e di composti contenenti esteri dell’acido ialuronico ottenuti mediante processo di electrospinning. Questa metodologia consente di realizzare matrici tridimensionali ad elevata porosità ed area superficiale da impiegare nella crescita in vitro di cellule, o nell’ambito della ricostruzione di tessuti danneggiati (tissue engineering).

Una delle principali patologie associate alla colecisti è la calcolosi biliare. I calcoli sono prevalentemente costituiti da colesterolo (o da bilirubinato di calcio), che viene in larga misura trasportato all’interno di micelle miste o vescicole, data la sua scarsa solubilità in acqua, e precipita sotto forma di cristalli in condizioni di sovrassaturazione. Nonostante i progressi compiuti in questo campo, che includono l’identificazione di diverse sostanze che agiscono come promotori o come inibitori della formazione di calcoli, le cause ed i meccanismi della calcolosi biliare sono tuttora oggetto di ricerca. Due fattori sembrano comunque giocare un ruolo fondamentale nella patogenesi dei calcoli biliari: elevate concentrazioni di calcio e di colesterolo nella bile, ed elevati tempi di residenza della bile nella colecisti. Data la complessità del problema, un approccio di tipo multidisciplinare appare essenziale. Così, per quanto riguarda il ruolo della concentrazione di colesterolo, le condizioni di sovrassaturazione della bile sono state studiate in letteratura mediante metodi chimico-fisici, che hanno portato alla costruzione di diagrammi di fase relativi ai tre principali componenti biliari, colesterolo, sali biliari e lecitina, opportunamente discolti in soluzione salina. Utlizzando tali sistemi modello, è stato possibile identificare, negli intervalli di composizione di rilevanza fisiologica, delle regioni in cui coesistono all’equilibrio una fase solida cristallina ed una fase micellare. Questo approccio ha permesso di definire un indice di sovrassaturazione del colesterolo rispetto alle condizioni di equilibrio, e quindi un indice di litogenicità della bile. Obiettivo di questo articolo è di fornire sia una rassegna dei dati riportati in letteratura che una presentazione dei risultati ottenuti nel nostro laboratorio sulla nucleazione e cristallizzazione del colesterolo in bile modello, discutendone le possibili implicazioni biologiche. L’apparato sperimentale da noi utilizzato consiste in una stazione di video microscopia ottica con tavolo portaoggetti e messa a fuoco motorizzati. I campioni di bile vengono introdotti in un apposito incubatore da microscopio a camicia d’acqua, che consente di controllare la temperatura con elevata precisione e stabilità per periodi estesi di osservazione (la scala di tempo degli esperimenti è di alcune settimane). Le varie fasi del processo di cristallizzazione vengono seguite acquisendo periodicamente immagini dei campioni all’interno dell’incubatore. A tal fine, i campioni vengono sottoposti ad una scansione automatica mediante il sistema di posizionamente motorizzato del microscopio, che viene gestito via computer attraverso un apposito codice di controllo. Le immagini acquisite vengono convertite in formato digitale e archiviate su disco, per essere successivamente processate mediante un software di analisi dell’immagine. Questa metodologia consente di misurare la velocità di crescita e la morfologia di singoli cristalli di colesterolo in funzione del tempo.

Edited by F.J. Martinez Boza, A. Guerrero, P. Partal, J. M. Franco, and J. Munoz

After having seen strategic delegation at work within firms, in this chapter we study how it may affect the organisation and the activity of the trade union.