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After the catastrophic fire at Notre Dame de Paris, a significant challenge was presented by the numerous lead-contaminated remnants. To address this, a detailed digitization strategy was devised and executed, tailored to the unique needs of this extensive and diverse corpus. This strategy involved the development and customization of both hardware and software tools, ensuring their effectiveness throughout the digitization process – from initial data acquisition to data dissemination.Central to our approach was the alignment of our methods with the distinct characteristics of each artifact, facilitating their effective preservation and future utility. Our strategy's adaptability was key, allowing us to incorporate advanced deep learning techniques into various aspects of our workflow. Notably, this included the implementation of the Segment Anything Model for automatic image segmentation, enhancing our image-based modeling capabilities. We also ventured into pioneering methods like 3D Gaussian Splatting and the exploration of radiance field methods for visualization.Moreover, the project has been mindful of data responsibility, aiming to make all digital data openly accessible beyond 2025. We have placed a strong emphasis on harmonizing and managing data, minimizing redundancies, and ensuring efficient storage, all while maintaining transparency about the limitations and errors in our methodologies. This holistic approach to digitization, balancing technological innovation with responsible data management, aims to preserve and make accessible the digital heritage of Notre Dame de Paris for future generations.

Neural Radiance Fields (NeRF or NeRFs) are to date emerging as a novel method for synthesizing novel views of complex 3D scenes, leveraging an artificial neural network to optimize a volumetric scene function using a set of input views. We conduct a preliminary critical review of the scientific and technical literature on NeRFs, and we highlight possible applications of the latter in the Cultural Heritage domain, for the image-based reconstruction of 3D models of real, multi-scale objects, even in combination with the more well-established photogrammetric techniques. A comparison is made between NeRFs and photogrammetry in terms of operating procedures and outputs (volumetric renderings vs. point clouds or meshes). It is demonstrated that NeRFs could be conveniently used for rendering objects (sculptures, archaeological remains, sites, paintings etc.) that are challenging for photogrammetry, typically: i) metallic, translucent, and/or transparent surfaces; ii) objects that present homogeneous textures; iii) occlusions, vegetation, and elements of very fine detail.

With the development of digital technologies in the documentation methods for cultural and architectural heritage, platforms and tools have emerged as solutions to collect, manage and produce data for multidisciplinary monitoring and studying purposes. In the context of an incident such as the fire of the Notre-Dame de Paris in April 2019, the considerable mobilization of the architects, scientists and researchers, has led the "digital data" working group to conceive a digital ecosystem capable to collect and integrate existing data, produce new data, share and archive, and finally structure and semantically enrich. One of the particular aspects of this works involves an approach to build a complete digital report of the Notre-Dame de Paris cathedral. With the help of photogrammetric acquisitions of the cathedral, leading to point clouds generation, projects were created in the aïoli platform. The structuring of the collected data (condition report, architectural descriptions, chemical and physical analysis…) has then led to the construction of semantic annotations, accompanied by description sheets and attachments. The vast multidisciplinary studies conducted on the cathedral as well as the large number of projects and annotations built over the course of 4 years constitute a singular collection of data, that will be the object of cross comparison and data interpretation in the future years.

The French 20th century heritage is in a situation of obligatory change within the framework of a societal transition. However, this change must be accompanied by a careful and precise look at the building so as not to lead to a complete banalization of the specific architecture of the different trends of the 20th century. These transformations have already started and are not dependent on research or patrimonialization for implementation. Technical solutions alone pose significant risks of architectural missteps. Thus this paper introduce a tool-based method for the production of systematic knowledge on this fragile "heritage". By applying it to a corpus of seven collective housing operations of the 20th century, as a framework for observing the development of analysis criteria, shaping the tools and confronting the reproducibility of the method, this paper seeks to present the proposals of objectification of gaze and memory, in an approach of openness and diversity of the knowledge (interdisciplinary scientifically, but also profane). Whether through dedicated visual representation or the use of conceptual models such as CIDOC-CRM, the ultimate goal is to examine the emergence of intrinsic protection for 20th-century architectural heritage by providing inhabitants access to the architecture and the knowledge produced through its objective analysis and explicit qualities, thereby enabling their acculturation. The objective is to question the perceived appearance of such protection.

Over the last decade, a large number of digital documentation projects have demonstrated the potential of image-based modelling of heritage objects in the context of documentation, conservation, and restoration. The inclusion of these emerging methods in the daily monitoring of the activities of a heritage restoration site (context in which hundreds of photographs per day can be acquired by multiple actors, in accordance with several observation and analysis needs) raises new questions at the intersection of big data management, analysis, semantic enrichment, and more generally automatic structuring of this data. In this article we propose a data model developed around these questions and identify the main challenges to overcome the problem of structuring massive collections of photographs through a review of the available literature on similarity metrics used to organise the pictures based on their content or metadata. This work is realized in the context of the restoration site of the Notre-Dame de Paris cathedral that will be used as the main case study.

Research in the field of Cultural Heritage is increasingly moving towards the creation of digital information systems, in which the geometric representation of an artifact is linked to some external information, through meaningful tags. The process of attributing additional and structured information to various elements in a given digital model is customarily identified with the term semantic annotation; the added contextual information is associated, for instance, to analysis and conservation terms. Starting from the existing literature, aim of this work is to discuss how semantic annotations are used, in digital architectural heritage models, to link the geometrical representation of an artefact with knowledge-related information. Most consolidated methods -such as traditional mapping on 2D media, are compared with more recent approaches making the most of 3D representation. Reference is made, in particular, to Heritage-BIM techniques and to collaborative reality-based platforms, such as Aïoli (http://aioli.cloud). Potentialities and limits of the different solutions proposed in literature are critically discussed, also addressing future research challenges in Cultural Heritage application fields.

Abstract Background The incidence of breech presentation in single pregnancies at term is between three to 5 %. In order to support eligible women in their choice of mode of delivery, a dedicated breech clinic with a care pathway was developed in December 2015 in a tertiary referral centre in Brussels. The primary objective of this study was to evaluate the vaginal birth rate before and after the introduction of a dedicated breech clinic. The secondary objective was to compare the early neonatal outcomes before and after the breech clinic was introduced. Methods This was a single centre retrospective and prospective study. The inclusion criteria were term (from 37 weeks), singleton fetus and breech presentation at delivery. The exclusion criteria were suspected intrauterine growth restriction, severe fetal malformations and intrauterine fetal demise. We used a composite outcome as an indicator of neonatal morbidity and mortality. Results After the introduction of the breech clinic, we observed a significant increase in planned vaginal delivery from 7.4% (12/162) to 53.0% (61/115) (OR: 13.5; 95% CI: 6.7–27.0). The effective vaginal breech delivery rate (planned and unexpected) significantly increased from 4.3% (7/162) pre-implementation of breech clinic to 43.5% (50/115) post-implementation (OR: 17.0; 95% CI: 7.3–39.6). Neonatal outcomes were not statistically different between the before and after periods. Conclusion The introduction of a dedicated breech clinic has led to an increase in vaginal deliveries for breech babies without adversely affecting neonatal outcomes.

The evolution of the digital technologies allowed since the early 1990s, to multiply the photogrammetric acquisitions, the digital and mechanical diagnosis and the 3D diagnosis of the sculptural heritage, generating a better knowledge of these objects. The multiplication of these tools therefore allowed to establish multidisciplinary methodologies, generally leading towards less invasive restorations protocol. Here, the diagnosis of a case study is first accomplished, starting with a photogrammetric acquisition, then tested in the two and three dimension annotation platform named aïoli, in order to determine the current possibilities for an innovative use of these tools, benefiting at the diagnosis of the sculptural heritage. On the order hand, along with the multiplication of the multidisciplinary methodologies, a very contemporary problematic arises: the need to improve the communication and discussion between different professionals. The goal was here to offer innovative methods to give all professionals the same vocabulary, a shared knowledge, therefore allowing a better diagnosis of these pieces of art.

Close-Range Photogrammetry (CRP) and Reflectance Transformation Imaging (RTI) are two of the most used image-based techniques when documenting and analyzing Cultural Heritage (CH) objects. Nevertheless, their potential impact in supporting study and analysis of conservation status of CH assets is reduced as they remain mostly applied and analyzed separately. This is mostly because we miss easy-to-use tools for of a spatial registration of multimodal data and features for joint visualisation gaps. The aim of this paper is to describe a complete framework for an effective data fusion and to present a user friendly viewer enabling the joint visual analysis of 2D/3D data and RTI images. This contribution is framed by the on-going implementation of automatic multimodal registration (3D, 2D RGB and RTI) into a collaborative web platform (AIOLI) enabling the management of hybrid representations through an intuitive visualization framework and also supporting semantic enrichment through spatialized 2D/3D annotations.

Image based-modeling practices in the field of Cultural Heritage studies are nowadays no longer seen as one-shot applications but as various and complex multimodal scenarios. Current use of SFM and photogrammetric methods implies their extensions to facilitate the management of complex multimodal data sets carried-out by different experts around a single heritage asset. In order to fully benefit of collaborative semantic enrichment of spatially oriented resources, a versatile and robust solution have been developed to enable incremental registration of image-sets within the web-based platform AIOLI. For this purpose, this paper will present an on-going development of a Totally Automated Co-registration and Orientations (TACO) work-flow.

In Italy, most of the cultivated walnuts belong to the Sorrento ecotype, and they are considered commercially valuable due to their specific organoleptic characteristics. The aim of this study is to evaluate and compare the morphological and compositional characteristics of walnuts sampled from ‘Sorrento’ trees cultivated in different locations in Campania and trees of both the ‘Chandler’ and ‘Sorrento’ varieties derived from the same location. The results demonstrated that ‘Sorrento’ and ‘Chandler’ walnuts have different biometric characteristics and a different fat content, with the highest fat content being found in the ‘Sorrento’ variety. Regarding the fatty acid (FA) composition, the content of monounsaturated and saturated fatty acids (MUFAs and SFAs) was highest in the ‘Sorrento’ variety (from 13 to 15% for MUFAs and from 11 to 13% for SFAs), while the polyunsaturated fatty acids (PUFAs) content was highest in the ‘Chandler’ variety (77%). The total phenolics content (TPC) was highest in the ‘Sorrento’ variety (from 910 to 1230 mg GAE/100 g), while no difference in γ-tocopherol content was found. Furthermore, the influence of walnut area cultivation was shown for fat content, FA composition and TPC. Therefore, both walnut varieties demonstrated good nutritional properties considering the PUFAs and γ-tocopherol content.

Cultural Heritage documentation and preservation has become a fundamental concern in this historical period. 3D modelling offers a perfect aid to record ancient buildings and artefacts and can be used as a valid starting point for restoration, conservation and structural analysis, which can be performed by using Finite Element Methods (FEA). The models derived from reality-based techniques, made up of the exterior surfaces of the objects captured at high resolution, are - for this reason - made of millions of polygons. Such meshes are not directly usable in structural analysis packages and need to be properly pre-processed in order to be transformed in volumetric meshes suitable for FEA. In addition, dealing with ancient objects, a proper segmentation of 3D volumetric models is needed to analyse the behaviour of the structure with the most suitable level of detail for the different sections of the structure under analysis. Segmentation of 3D models is still an open issue, especially when dealing with ancient, complicated and geometrically complex objects that imply the presence of anomalies and gaps, due to environmental agents such as earthquakes, pollution, wind and rain, or human factors. The aims of this paper is to critically analyse some of the different methodologies and algorithms available to segment a 3D point cloud or a mesh, identifying difficulties and problems by showing examples on different structures.

In the field of wall paintings studies different imaging techniques are commonly used for the documentation and the decision making in term of conservation and restoration. There is nowadays some challenging issues to merge scientific imaging techniques in a multimodal context (i.e. multi-sensors, multi-dimensions, multi-spectral and multi-temporal approaches). For decades those CH objects has been widely documented with Technical Photography (TP) which gives precious information to understand or retrieve the painting layouts and history. More recently there is an increasing demand of the use of digital photogrammetry in order to provide, as one of the possible output, an orthophotomosaic which brings a possibility for metrical quantification of conservators/restorators observations and actions planning. This paper presents some ongoing experimentations of the LabCom MAP-CICRP relying on the assumption that those techniques can be merged through a common pipeline to share their own benefits and create a more complete documentation.

The primary purpose of the survey for the restoration of Cultural Heritage is the interpretation of the state of building preservation. For this, the advantages of the remote sensing systems that generate dense point cloud (range-based or image-based) are not limited only to the acquired data. The paper shows that it is possible to extrapolate very useful information in diagnostics using spatial annotation, with the use of algorithms already implemented in open-source software. Generally, the drawing of degradation maps is the result of manual work, so dependent on the subjectivity of the operator. This paper describes a method of extraction and visualization of information, obtained by mathematical procedures, quantitative, repeatable and verifiable. The case study is a part of the east facade of the Eglise collégiale Saint-Maurice also called Notre Dame des Grâces, in Caromb, in southern France. The work was conducted on the matrix of information contained in the point cloud asci format. The first result is the extrapolation of new geometric descriptors. First, we create the digital maps with the calculated quantities. Subsequently, we have moved to semi-quantitative analyses that transform new data into useful information. We have written the algorithms for accurate selection, for the segmentation of point cloud, for automatic calculation of the real surface and the volume. Furthermore, we have created the graph of spatial distribution of the descriptors. This work shows that if we work during the data processing we can transform the point cloud into an enriched database: the use, the management and the data mining is easy, fast and effective for everyone involved in the restoration process.

The history and identity of the Avignon’s bridge is inseparable from that of the Rhône river. Therefore, in order to share the history and memory of the Rhône, it is essential to get to know this bridge and especially to identify and make visible the traces of its past, its construction, its interaction with the river dynamics, which greatly influenced his life. These are the objectives of the PAVAGE project that focuses on digitally surveying, modelling and re-visiting a heritage site of primary importance with the aim of virtually restoring the link between the two sides which, after the disappearance of the Roman bridge of Arles, constituted for a long time the only connection between Lyon or Vienna and the sea. Therefore, this project has an important geo-historical dimension for which geo-morphological and paleoenvironmental studies were implemented in connection with the latest digital simulation methods exploiting geographic information systems. By integrating knowledge and reflections of archaeologists, historians, geomorphologists, environmentalists, architects, engineers and computer scientists, the result of this project (which involved 5 laboratories during 4 years) is a 3D digital model covering an extension of 50 km2 achieved by integrating satellite imagery, UAV-based acquisitions, terrestrial laser scanning and photogrammetry, etc. Beyond the actions of scientific valorisation concerning the historical and geomorphological dimensions of the project, the results of this work of this interdisciplinary investigation and interpretation of this site are today integrated within a location-based augmented reality application allowing tourists to exploring the virtual reconstruction of the bridge and its environment through tablets inside the portion of territory covered by this project (between Avignon and Villeneuve-lez-Avignon). This paper presents the main aspects of the 3D virtual reconstruction approach.

In recent years, advances in the fields of photogrammetry and computer vision have produced several solutions for generating 3D reconstruction starting from simple images. Even if the potentialities of the image-based 3D reconstruction approach are nowadays very well-known in terms of reliability, accuracy and flexibility, there is still a lack of low-cost, open-source and automated solutions for collecting mass of archaeological findings, specially if one consider the real (and non theoretical) contextual aspects of a digitization campaign on the field (number of objects to acquire, available time, lighting conditions, equipment transport, budget, etc...) as well as the accuracy requirements for an in-depth shape analysis and classification purpose. In this paper we present a prototype system (integrating hardware and software) for the 3D acquisition, geometric reconstruction, documentation and archiving of large collections of archaeological findings. All the aspects of our approach are based on high-end image-based modeling techniques and designed basing on an accurate analysis of the typical field conditions of an archaeological campaign, as well as on the specific requirements of archaeological finding documentation and analysis. This paper presents all the aspects integrated into the prototype: - a hardware development of a transportable photobooth for the automated image acquisition consisting of a turntable and three DSLR controlled by a microcontroller; - an automatic image processing pipeline (based on Apero/Micmac) including mask generation, tie-point extraction, bundle adjustment, multi-view stereo correlation, point cloud generation, surface reconstruction; - a versatile (off-line/on-line) portable database for associating descriptive attributes (archaeological description) to the 3D digitizations on site; - a platform for data-gathering, archiving and sharing collections of 3D digitizations on the Web. The presentation and the assessment of this prototype is based on an interdisciplinary experience carried out on the study of the Tholos in Delphi within the framework of the CNRS's Eloquentia project and the EFA's archaeological program.

This paper discusses a methodology to evaluate the accuracy of recently developed image-based 3D modelling techniques. So far, the emergence of these novel methods has not been supported by the definition of an internationally recognized standard which is fundamental for user confidence and market growth. In order to provide an element of reflection and solution to the different communities involved in 3D imaging, a promising approach is presented in this paper for the assessment of both metric quality and limitations of an open-source suite of tools (Apero/MicMac), developed for the extraction of dense 3D point clouds from a set of unordered 2D images. The proposed procedural workflow is performed within a metrological context, through inter-comparisons with "reference" data acquired with two hemispherical laser scanners, one total station, and one laser tracker. The methodology is applied to two case studies, designed in order to analyse the software performances in dealing with both outdoor and environmentally controlled conditions, i.e. the main entrance of Cathédrale de la Major (Marseille, France) and a custom-made scene located at National Research Council of Canada 3D imaging Metrology Laboratory (Ottawa). Comparative data and accuracy evidence produced for both tests allow the study of some key factors affecting 3D model accuracy.

In the domain of conservation and promotion of cultural heritage, the development of new information technologies offers new tools for sharing knowledge on heritage building. These tools are destined to help experts to enrich and access information about buildings. This article proposes an approach allowing the automatic transfer of annotations in a set of spatially-oriented photographs (whose positions and orientations in space are estimated) by using 3D information. First of all, an automated image-based 3D reconstruction method produces 3D information (specifically 3D coordinates) by processing photographs of the set. Then, the process of annotations' transfer between images uses this generated 3D information. Finally, this process allows the implementation of the annotations modification. As a consequence, this process provides a simple way to annotate blocs of images all at once instead of one by one.

In order to handle more efficiently projects of restoration, documentation and maintenance of historical buildings, it is essential to rely on a 3D enriched model for the building. Today, the concept of Building Information Modelling (BIM) is widely adopted for the semantization of digital mockups and few research focused on the value of this concept in the field of cultural heritage. In addition historical buildings are already built, so it is necessary to develop a performing approach, based on a first step of building survey, to develop a semantically enriched digital model. For these reasons, this paper focuses on this chain starting with a point cloud and leading to the well-structured final BIM; and proposes an analysis and a survey of existing approaches on the topics of: acquisition, segmentation and BIM creation. It also, presents a critical analysis on the application of this chain in the field of cultural heritage.

Because of its low-cost and ease in use, 3D reconstruction from sets of images has an great potential for enhancing cultural heritage documentation, conservation and valuation. However, these technologies, from image acquisition to final 3D model obtaining, are often difficult to master for non-expert people. Our work consists in developing a series of acquisition protocols for the museum's photographs. The end-goal being to enable those professionals to generate efficiently and easily 3D models of heritage artefact.

The paper will describe a new approach based on the development of a procedural modelling methodology for archaeological data representation. This is a custom-designed solution based on the recognition of the rules belonging to the construction methods used in roman times. We have conceived a tool for 3D reconstruction of masonry structures starting from photogrammetric surveying. Our protocol considers different steps. Firstly we have focused on the classification of opus based on the basic interconnections that can lead to a descriptive system used for their unequivocal identification and design. Secondly, we have chosen an automatic, accurate, flexible and open-source photogrammetric pipeline named Pastis Apero Micmac – PAM, developed by IGN (Paris). We have employed it to generate ortho-images from non-oriented images, using a user-friendly interface implemented by CNRS Marseille (France). Thirdly, the masonry elements are created in parametric and interactive way, and finally they are adapted to the photogrammetric data. The presented application, currently under construction, is developed with an open source programming language called Processing, useful for visual, animated or static, 2D or 3D, interactive creations. Using this computer language, a Java environment has been developed. Therefore, even if the procedural modelling reveals an accuracy level inferior to the one obtained by manual modelling (brick by brick), this method can be useful when taking into account the static evaluation on buildings (requiring quantitative aspects) and metric measures for restoration purposes.

Today with the development of new information technologies, the domain of conservation and promotion of cultural heritage benefits from new tools to disseminate knowledge on heritage buildings. These tools are intended to help experts to enrich and access information about buildings. This paper describes this critical issue and proposes an approach permitting the automatic transfer of annotations in a set of oriented photographs (whose positions and orientations in space are known) by using 3D information. First of all, photographs are processed with an automated image-based 3D reconstruction method to produce 3D information (specifically 3D coordinates). Then, 3D information is used in the process of annotations’ transfer between images. Finally, with this process, the modification of annotations can be easily implemented. As a consequence, this process provides a simple way to annotate blocs of images all at once instead of one by one.

Today, we need 3D models of heritage buildings in order to handle more efficiently projects of restoration, documentation and maintenance. In this context, developing a performing approach, based on a first phase of building survey, is a necessary step in order to build a semantically enriched digital model. For this purpose, the Building Information Modeling is an efficient tool for storing and exchanging knowledge about buildings. In order to create such a model, there are three fundamental steps: acquisition, segmentation and modeling. For these reasons, it is essential to understand and analyze this entire chain that leads to a well- structured and enriched 3D digital model. This paper proposes a survey and an analysis of the existing approaches on these topics and tries to define a new approach of semantic structuring taking into account the complexity of this chain.

The site of Qal'at Sem'an, located in the north of Syria, was built in the honor of Saint Simeon around the column on the top of which he lived many years and died in 459. Since 2003, this site has been the object of digital surveys which covered the major part of the area. The sanctuary (Qal'at Sem'an) and the village (Deir Sem'an) are composed of different types of edifices; this variety gives us a large field of studies. Several surveying methods were applied on these sectors according to the morphology of the analyzed parts and to the analysis needs. This article presents a case study based on a combination of different digital measurement and modeling techniques for the virtual reconstruction of various parts of this complex site. As this work is conducted over several years, different acquisition tools have been experimented for image-based and range-based 3D modeling. In particular, we focus on the "Residence", a civil building of the 6th century which probably was an oil mill. We will describe the anastylosis process founded firstly on the digital surveying, secondly on the 3D model structuring and finally on the information interfacing by using NUBES, an integrated platform for describing, analyzing, documenting and sharing digital representations of heritage buildings. The final goal of our work is to evaluate the relevance of the survey / modeling / semantic structuring workflow for an effective analysis of a complex site.

During the modelling process, 3D models are not easily conceived to support changes over time. On the contrary, for the description of cultural heritage, it is often necessary to display not only the actual state of buildings but also their previous states so to understand their modifications. The construction and structuring of spatio-temporal models of cultural heritage demand a double conceptual effort: on one side, 3D models must be reconstructed and structured in space according to architectural concepts; on the other one, such elements should follow the criteria of temporal decomposition. For this reason, links between structured elements should be established to keep track of changes over time. Moreover, only the current state can be reconstructed in a rigorous way using a combination of different 3D measurement techniques (such as laser scanning and photogrammetry); on the contrary, knowledge about past states is conditioned by missing elements, whose morphology and dating can reveal uncertain. For this reason, this paper describes a methodological approach to make use of the existing iconographic corpus for the analysis and the 3D management of building transformations. The aim is to establish a relation between the iconography used for the hypothetical reconstruction and the 3D representation that depends on it. As a result, 3D representations can be used like visualization systems capable of reflecting the amount of knowledge produced studying historic buildings.

The article describes a pipeline, based on image-data, for the 3D reconstruction of building façades or architectural elements and the successive modeling using geometric primitives. The approach overcome some existing problems in modeling architectural elements and deliver efficient-in-size reality-based textured 3D models useful for metric applications. For the 3D reconstruction, an opensource pipeline developed within the TAPENADE project is employed. In the successive modeling steps, the user manually selects an area containing an architectural element (capital, column, bas-relief, window tympanum, etc.) and then the procedure fits geometric primitives and computes disparity and displacement maps in order to tie visual and geometric information together in a light but detailed 3D model. Examples are reported and commented.

This paper reviews some experimental measurements of convective heat transfer coefficient distributions which are connected with the cooling of gas turbines, performed by the authors’ research group at the University of Naples Federico II with infrared thermography. Measurements concern impinging jets, cooling of rotating disks, and gas turbine blades, which are either stationary or rotating. The heated thin foil sensor, associated with the detection of surface temperature by means of infrared thermography, is exploited to accurately measure detailed convective heat transfer coefficient maps. The paper also intends to show how to correctly apply the infrared technique in a variety of gas turbines cooling problems.

An analysis is conducted on a catalogue containing more than 2000 seismic events occurred in the southern Tyrrhenian Sea between 1988 and October 2002, as an attempt to characterise the main seismogenetic processes active in the area in space, time and magnitude domain by means of the parameters of phenomenological laws. We chose to adopt simple phenomenological models, since the low number of data did not allow to use more complex laws. The two main seismogenetic volumes present in the area were considered for the purpose of this work. The first includes a nearly homogeneous distribution of hypocentres in a NW steeply dipping layer as far as about 400 km depth. This is probably the seismological expression of the Ionian lithospheric slab subducting beneath the Calabrian Arc. The second contains hypocentres concentrated about a sub-horizontal plane lying at an average depth of about 10 km. It is characterised by a background seismicity spread all over the area and by clusters of events that generally show a direction of maximum elongation. The parameters of the models describing seismogenetically homogeneous subsets of the earthquake catalogue in the three analysis domains, along with their confidence intervals, are estimated and analysed to establish whether they can be regarded as representative of a particular subset.

We performed an analysis of refraction data recorded in Italy since 1968 in the frame of the numerous deep seismic sounding and wide-angle reflection/refraction projects. The aims of this study are to construct a parametric database including the recording geometric information relative to each profile, the phase pickings and the results of some kinematic analyses performed on the data, and to define a reference 1D velocity model for the Italian territory from all the available refraction data. As concerns the first goal, for each seismic section we picked the P-wave first-arrival-times, evaluated the uncertainties of the arrival-times pickings and determined from each travel time-offset curve the 1D velocity model. The study was performed on 419 seismic sections. Picking was carried out manually by an algorithm which includes the computation of three picking functions and the picking- error estimation. For each of the travel time-offset curves a 1D velocity model has been calculated. Actually, the 1D velocity-depth functions were estimated in three different ways which assume: a constant velocitygradient model, a varying velocity-gradient model and a layered model. As regards the second objective of this work, a mean 1D velocity model for the Italian crust was defined and compared with those used for earthquake hypocentre locations and seismic tomographic studies by different institutions operating in the Italian area, to assess the significance of the model obtained. This model can be used in future works as input for a next joint tomographic inversion of active and passive seismic data.

The northern coast of Sicily and its offshore area represent a hinge zone between a sector of the Tyrrhenian Basin, characterized by the strongest crustal thinning, and the sector of the Sicilian belt which has emerged. This hinge zone is part of a wider W-E trending right-lateral shear zone, which has been affecting the Maghrebian Chain units since the Pliocene. Seismological and structural data have been used to evaluate the seismotectonic behavior of the area investigated here. Seismological analysis was performed on a data set of about 2100 seismic events which occurred between January 1988 and October 2002 in the Southern Tyrrhenian Sea. This paper focuses in particular on a set of data relating to the period from 6th September 2002, including both the main shock and about 540 aftershocks of the Palermo seismic sequence. The distribution of the hypocenters revealed the presence of two main seismogenic zones. The events of the easternmost zone may be related to the Ionian lithospheric slab diving beneath the Calabrian Arc. The seismicity associated with the westernmost zone is closely clustered around a sub-horizontal regression plane contained within the thinned Southern Tyrrhenian crust, hence suggesting that this seismogenic zone is strictly connected to the deformation field active within the hinge zone. On the basis of both structural and seismological data, the brittle deformation pattern is characterized by high-angle faults, mainly represented by transcurrent synthetic right-lateral and antithetic left-lateral systems, producing both restraining/uplifting and releasing/subsiding zones which accommodate strains developing in response to the current stress field (characterized by a maximum axis trending NW-SE) which has been active in the area since the Pliocene. The cluster of the seismic sequence which started with the 6th September 2002's main shock is located within the hinge zone. The distribution of the hypocenters relative to this sequence emphasizes the presence of a high-angle NE-SW-oriented deformation belt within which several shear surfaces are considered to be found sub-parallel to that established for the main shock. The kinematics of all these structures is consistent with a compressive right-lateral focal mechanism.

Estimates of the fractal dimension of hypocentral distributions require evaluating the range of independent variables in which fractal parameters exhibit a power law. Systematic and accidental errors are produced mainly by the subjective selection of this range, the insufficiency of data sets as well as by hypocenter mislocations. Therefore it is very important to determine the confidence intervals which are associated with fractal dimension estimates. The effects of various sources of errors are studied using different geometric clusters of epicenters, which have been synthetically generated using a multicluster algorithm with different hierarchical levels, so as to reproduce some characteristics of the patterns typical of real epicenter distributions. Subsequently, groups of differently sized subsets of synthetic epicenters were obtained by randomly sampling each distribution. Confidence intervals of fractal dimensions were thus calculated using all the estimates obtained for the various subsets. This procedure was also tested on real seismic data, consisting of epicentral distributions in three Sicilian areas and five clusters of mining-induced seismic events (Wujek coal mine, Poland). In that analysis both correlation dimensions and their confidence intervals were taken into account.

A study was conducted to determine whether retinyl phosphate would act as substrate for the enzymatic synthesis of mannosyl retinyl phosphate. Retinyl phosphate, prepared chemically, supported the growth of vitamin A-deficient rats at the same rate as retinol. It also stimulated the uptake of [14C]mannose from GDP-[14C]mannose into total chloroform-methanol extractable lipid. This reaction occurred in the presence of ATP, Mn2+, detergent (Zonyl A), and a membrane-rich enzyme preparation from the livers of vitamin A-deficient rats, provided that a lipid extract of the membrane preparation of α-L-lecithin was also added. Total chloroform-methanol-extractable, labeled mannolipid was separated into two principal labeled mannolipids by thin-layer or column chromatography or by differential solvent extraction. The properties of these mannolipids identified them as glycophospholipids: one was identical with authentic synthetic dolichyl mannosyl phosphate, and the other was concluded to be mannosyl retinyl phosphate because of its incorporation of radioactivity from [3H]retinyl phosphate, its rapid hydrolysis by dilute acid, and the formation of substance that cochromatographed with retinol upon its acid hydrolysis. The presence of ATP or GTP was essential for the stimulation of mannolipid synthesis, probably because of their protective action on the substrates against phosphatases present in the crude enzyme fraction. A pH of 6.0-6.2 favored the formation of dolichyl mannosyl phosphate; a higher pH (6.7-7.0) that of mannosyl retinyl phosphate.