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In revision total hip arthroplasty, achieving robust fixation is difficult and implant movement may occur over time. Bone may also rearrange around the implant as a result of mechanical loading, making the measurement of migration challenging. The study aimed to quantify changes in bone shape and implant position 1 year following acetabular reconstruction using custom three‐dimensional‐printed cups. This observational retrospective cohort study involved 23 patients with Paprosky type IIIB defects. Postop computed tomography scans taken within 1 week of surgery and at 1‐year postsurgery were co‐registered and analyzed. Three co‐registration strategies were implemented including bone‐to‐bone and implant‐to‐implant. (1) Co‐registration of the ipsilateral innominate bone (diseased anatomy) was used to measure changes in implant position. (2) Co‐registration of the implant was carried out to quantify changes in the ipsilateral innominate bone shape. (3) Co‐registration of the contralateral innominate bone (nondiseased anatomy) was performed to measure changes in the ipsilateral innominate bone shape and implant position. The median centroid distances (interquartile range [IQR]) were 2.3 mm (IQR: 3.7–1.7 mm) for changes in implant position, 2.4 mm (IQR: 3.6–1.6 mm) for changes in ipsilateral innominate bone shape, and 3.7 mm (IQR: 4.6–3.5 mm) for changes in ipsilateral innominate bone shape and implant position. Following acetabular reconstruction, implant movements and periprosthetic bone remodeling are physiological and of a similar extent. Surgeons and engineers should consider this when performing implant monitoring in these patients. [ABSTRACT FROM AUTHOR]

The interest in archival research applied to archaeology has never waned, and indeed in recent years we have witnessed a new interest, at least in the study of pre-Roman Italy. Broader theoretical considerations have gone hand in hand with targeted research on specific contexts, and specific personalities have been reread. In this context, the studies of the Tyrrhenian area have reached a particular level of detail for some case studies and have allowed, among other things, to highlight secondary actors on the stage of archaeological research, whose contribution was fundamental, especially with regard to the phases of discovery and study of those contexts that often still constitute the foundations on which the history of entire territories is based today. So far, this type of focus has mainly been placed on the first fifty years after the unification of Italy, but it is clearly possible to extend it to more recent periods. This is exactly what is being attempted with the study of the so-called Carte Bracci, an archive fund at the Archaeological Museum of the Agro Falisco, which is being reported on here for the first time. The Carte Bracci are an essential tool for researchers working on the area north of Rome, between Capena and Orte, which was under the supervision of the ‘Custode di zona’ Arcangelo Bracci during his years of service to the State (1950-1975). A brief biographical sketch of Arcangelo Bracci, written by a person who knew him personally, is presented, followed by a description of the structure of the collection and the selection of a specific case study – that of the quarries and their impact on the territory – which is particularly relevant to shed light on his activity in the area. Finally, considering the relevance of the documentation, the research and dissemination potential of the current study is outlined. [ABSTRACT FROM AUTHOR]

The study of the Faliscan region in the pre-Roman period is one of the lines of research of the Dipartimento di Scienze dell’Antichità, Sapienza Università di Roma. The main sites of the area were extensively investigated in the decades between the end of the 19th and be‑ ginning of the 20th century, and were widely reconsidered over the last thirty years. Since 2011, a new project has been structured focusing on Falerii (Civita Castellana, VT), the main center of the region. Finally, since 2019, a new season of field investigations has been underway on the Vignale hill, one of the two hills on which the ancient city stood. This new series of activities has been also an opportunity to reflect on the role that a scientific mission and a research team can play in a territory, in which the value of the archaeological heritage is not always fully recognised, also questioning how to involve the local community in all its facets. It was immediately clear that it was necessary to act on several levels, in an attempt to involve different parts of the population. A multilayered dissemination project was therefore structured. The project was articulated in various actions, focused on different parts of the ongoing research and was carried out in strict collaboration with the local community. The paper presents the first results of this dissemination path: a tactile experience, also intended for the dif‑ ferently-abled audience, and new visit itineraries for the Archaeological Museum of the Agro Falisco (Forte Sangallo, Civita Castellana, VT). [ABSTRACT FROM AUTHOR]

In this work, the consolidation efficiency of SiO2 nanoparticles (synthesized in the Chemistry laboratories at the Tor Vergata University of Roma) was tested on Pietraforte sandstone surfaces belonging to the bell tower of San Lorenzo (Florence, Italy) and was fully investigated. Nanoparticles (synthesized in large-scale mass production) have been characterized by XRD—X-Ray Diffraction; Raman and FTIR—Fourier Transform Infrared spectroscopy; SEM—Scanning Electron Microscopy; while the Pietraforte sandstone morphology was examined by Porosimetry, capillary absorption test, surface hardness test, drilling resistance and tensile strength. The colorimetric measurements were also performed to characterize the optical modification exhibited by Pietraforte sandstones, especially after the SiO2 treatments. Our results show that applying to the Pietraforte, the new consolidating agent based on SiO2 nanoparticles, has several advantages, as they are more resistant to perforation, wear, and abrasion even long range (for long times of exposure and consolidating exercise against Florentine sandstone), compared to the CaCO3 nanoparticles (tested in our previous paper), which instead show excellent performance but only close to their first application. This means that over time, their resistance to drilling decreases, they wear much more easily (compared to SiO2-treated sandstone), and tend to exhibit quite a significant surface abrasion phenomena. The experimental results highlight that the SiO2 consolidation efficiency on this kind of Florentine Pietraforte sandstone (having low porosity and a specific calcitic texture) seems to be higher in terms of water penetration protection, superficial cohesion forces, and an increase in surface resistance. Comparing the performance of SiO2 nanoparticles with commercial consolidants in solvents such as Estel 1000 (tested here), we demonstrate that: (A) the restorative effects are obtained with a consolidation time over one week, significantly shorter when compared to the times of Estel 1000, exceeding 21 days; (B) SiO2 nanoparticles perform better than Estel 1000 in terms of cohesion forces, also ensuring excellent preservation of the optical and color properties of the parent rock (without altering it after application). [ABSTRACT FROM AUTHOR]

Large acetabular bone defects are challenging in hip revision surgery. Clinical assessment is crucial to evaluate modern technologies in surgical reconstruction. We aimed to better understand the bone remodeling that occurs following acetabular reconstruction. Our objectives were: (1) To characterize changes in the shape of the pelvis by studying sequential computed tomography (CT) scans collected immediately and 1‐year postoperatively and (2) to identify which part of the pelvis is most susceptible to remodeling. We used the CT scans taken at two timepoints, of 24 patients with acetabular bone defects classified as Paprosky IIIB, treated with three‐dimensional (3D)‐printed custom‐made acetabular implants. Segmented 3D models of the bony pelvis were co‐registered using three different techniques. A global co‐registration of the full pelvis was conducted, followed by the co‐registration of the innominate bone and then ilium only, on the ipsilateral reconstructed side. The relative movements of the ilium, ischium, and pubis were analyzed from visual inspection and using co‐registration metrics (root mean square error and intersection over union). No bone remodeling was found in 14/24 patients (58%). The co‐registration of the innominate bone indicated bone remodeling in five cases (21%), while the remaining five cases (21%) presented remodeling in the global co‐registration but not the innominate bone co‐registration, suggestive of changes occurring at the sacroiliac joint. Changes in the pelvic shape were greatest at the pubis and ischium. Bone remodeling may occur in complex cases of Paprosky type IIIB defects, after acetabular reconstruction (occurrence of 21%, 5/24 cases). Surgeons and engineers should consider this when monitoring implant migration. [ABSTRACT FROM AUTHOR]

Patients with advanced cancer undergoing chest wall resection may require reconstruction. Currently, rib prostheses are created by segmenting computed tomography images, which is time-consuming and labour intensive. The aim was to optimise the production of digital rib models based on a patient's age, weight, height and gender. A statistical shape model of human ribs was created and used to synthetise rib models, which were compared to the ones produced by segmentation and mirroring. The segmentation took 11.56±1.60 min compared to 0.027 ±0.009 min using the new technique. The average mesh error between the mirroring technique and segmentation was 0.58±0.25 mm (right ribs), and 0.87±0.18 mm (left ribs), compared to 1.37±0.66 mm ( ) and 1.68 ±0.77 mm ( ), respectively, for the new technique. The new technique is promising for the efficiency and ease-of-use in the clinical environment. Clinical Relevance- This is an optimised 3D modelling method providing clinicians with a time-efficient technique to create patient-specific rib prostheses, without any expertise or software knowledge required.

A multitude of pharmacokinetics studies have been published. However, due to the lack of an open database, pharmacokinetics data, as well as the corresponding meta-information, have been difficult to access. We present PK-DB (https://pk-db.com), an open database for pharmacokinetics information from clinical trials. PK-DB provides curated information on (i) characteristics of studied patient cohorts and subjects (e.g. age, bodyweight, smoking status, genetic variants); (ii) applied interventions (e.g. dosing, substance, route of application); (iii) pharmacokinetic parameters (e.g. clearance, half-life, area under the curve) and (iv) measured pharmacokinetic time-courses. Key features are the representation of experimental errors, the normalization of measurement units, annotation of information to biological ontologies, calculation of pharmacokinetic parameters from concentration-time profiles, a workflow for collaborative data curation, strong validation rules on the data, computational access via a REST API as well as human access via a web interface. PK-DB enables meta-analysis based on data from multiple studies and data integration with computational models. A special focus lies on meta-data relevant for individualized and stratified computational modeling with methods like physiologically based pharmacokinetic (PBPK), pharmacokinetic/pharmacodynamic (PK/PD), or population pharmacokinetic (pop PK) modeling., (© The Author(s) 2020. Published by Oxford University Press on behalf of Nucleic Acids Research.)

A study of the optical transmission of low-loss W1.5 photonic crystal waveguides built on silicon membranes and operating at telecom wavelengths is presented. The feasibility of performing all-optical switching is demonstrated for W1.5 waveguides coupled with L3 cavities, systems amenable for incorporation in on-chip devices. Switching of waveguide transmission is achieved by means of optical excitation of free carriers using a 2.5 ns pump laser. Experimental results are reproduced by finite-difference time-domain simulations which model the response of the finite system and band structure calculations describing the infinite, ideal one.