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In Northern Tigray (Ethiopia), the combined presence in the valley bottoms of sedimentary fills several meters thick and of archaeological remains of human settlements (homes, camps) raises the question of the socio-environmental processes at the origin of these deposits and their interactions with human populations. However, in certain (national, legislative) contexts, it can be difficult to apply very advanced techniques or to perform a large number of analyses. This paper shows that a chronostratigraphic approach based on laser granulometry, loss on ignition and radiocarbon dating provides satisfactory answers to the main geoarchaeological questions. Our specific objective was to reconstruct the landscape and environmental changes in the region around the Wakarida archaeological site, based on the sedimentary deposits in the valley bottoms. These deposits are now cultivated by the inhabitants, thanks to the construction of agricultural terraces in the 20th century. Archaeological excavations unearthed an urban settlement at Wakarida which dates from the classical Aksumite (150–400/450 AD) and post-Aksumite (800/850 AD) periods, and traces of earlier archaeological occupations (pre- and proto-Aksumite periods, 800–50 BC) in the study area. These remains raise questions about the influence of societies on their environment. A method based on a combination of fieldwork, sedimentological analyses and dating was used to answer these questions. This chronostratigraphic study is partially based on the identification of chronological inversions, revealing ablation and depositional phases in the sedimentary cascades, which have to be taken into account to understand the evolution of the site. We identified several phases in the establishment of the present-day landscape around the Wakarida site. During the Northgrippian (Early Holocene), the valleys were progressively filled by low-energy alluvial and/or colluvial processes. During the Meghalayan (Middle Holocene), ablation processes alternated with depositions resulting from climatic processes and possible anthropogenic influences. From the 1st millennium BC, the impact of the population on its environment (deforestation) has resulted in chronological inversions in the deposits, particularly around the 14th and 17th centuries AD.

A lot of evidence has shown the importance of stimulating cell mechanically during bone repair. In this study, we modeled the challenging fracture healing of a large bone defect in tibial diaphysis. To fill the fracture gap, we considered the implantation of a porous osteoconductive biomaterial made of poly-lactic acid wrapped by a hydrogel membrane mimicking osteogenic properties of the periosteum. We identified the optimal loading case that best promotes the formation and differentiation into bone tissue. Our results support the idea that a patient's rehabilitation program should be adapted to reproduce optimal mechanical stimulations. [ABSTRACT FROM AUTHOR]

This study aims at suggesting a new approach to peri-implant healing models, providing a set of taxis-diffusion-reaction equations under the combined influence of mechanical and biochemical factors. Early events of osseointegration were simulated for titanium screw implants inserted into a pre-drilled trabecular bone environment, up to 12 weeks of peri-implant bone healing. Simulations showed the ability of the model to reproduce biological events occurring at the implant interface through osteogenesis. Implants with shallow healing chamber showed higher proportions of lamellar bone, enhanced by the increase of mechanical stimulation. Osteoconduction was observed through the surface treatment model and similar bone healing patterns compared to in vivo studies. [ABSTRACT FROM AUTHOR]

During the First World War, a significant part of the fights took place in the Balkans, on a front line running along the borders of Albania, Bulgaria, Greece and North Macedonia. They left a lasting footprint on the landscapes, which remains less precisely assessed than on the Western Front. However, a century after the end of the war, traces or consequences are still perceptible. Opposing armies left behind many remnants such as fortifications or defensive works, a dense network of trenches, small railways, grounds which were heavily destroyed by artillery fire or even villages totally ruined and sometimes never reoccupied. Identifying these "polemoforms" can find its place in various approaches devoted to the landscape: knowledge of its historical evolution and of the degree of disappearance of the war footprints, characterization of their memorial value, protection of the historical legacy, identification of grounds likely to keep buried ammunition leftovers. This communication will present the contribution of French cartographic and photographic archives dating from the First World War and recent satellite images to identify the traces left by that military conflict and assess their persistence in current landscapes. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to assess, through biological analysis, the local effects and osseointegration of dental implants incorporating surface micro/nanofeatures compared with implants of identical design without surface treatment. Background: Known to impact bone cell behavior, surface chemical and topography modifications target improved osseointegration and long‐term success of dental implants. Very few studies assess the performance of implants presenting both micro‐ and nanofeatures in vivo on the animal models used in preclinical studies for medical device certification. Methods: Implant surfaces were characterized in terms of topography and surface chemical composition. After 4 weeks and 13 weeks of implantation in sheep femoral condyles, forty implants were evaluated through micro‐computed tomography, histopathologic, and histomorphometric analyses. Results: No local adverse effects were observed around implants. Histomorphometric analyses showed significantly higher bone‐to‐implant contact in the coronal region of the surface‐treated implant at week 4 and week 13, respectively, was 79.3 ± 11.2% and 86.4 ± 6.7%, compared with the untreated implants (68.3 ± 8.8% and 74.8 ± 13%). Micro‐computed tomography analyses revealed that healing patterns differed between coronal and apical regions, with higher coronal bone‐to‐implant contact at week 13. Histopathologic results showed, at week 13, bone healing around the surface‐treated implant with undistinguishable defect margins, while the untreated implant still presented bone condensation and traces of the initial drill defect. Conclusion: Our results suggest that the surface‐treated implant not only shows no deleterious effects on local tissues but also promotes faster bone healing around the implant. [ABSTRACT FROM AUTHOR]

Knowledge of landscapes evolution can be useful for environment or geoheritage management or protection. It can provide also key-information to foresee future dynamics and evolutions or a framework to analyse environmental perception and sensitivity. Photograph, combined with other documentary sources as old maps, satellite images or travellers' narratives is one of the best mean to document changes that occurred over the 150 last years. This contribution will present some historical photographic archives available for studying Balkan landscapes from the beginning of the 20th century onwards, but that remain little known and used. The integration of data into a geographical information system (GIS) allows the assessment of landscape evolution and comparisons both in time and in space. Through two case studies selected in North Macedonia, we will show that diachronic analysis may concern both vegetation covers, and changes that have affected river system. These examples document the great changes that occurred in landscapes through the 20th century. They could contribute both to a better knowledge of biophysical processes over the "longue durée", by connecting to geoarchaeological or palaeoenvironmental researches, both to writing an environmental history of this part of Europe. [ABSTRACT FROM AUTHOR]

This paper demonstrates the use of surface plasmon resonance of core–shell Ag@TiO2 particles in SHINERS experiments. A copper(ii) complex grafted onto Ag@TiO2 surface was probed by Raman spectroscopy using resonance excitation profiles vs. excitation wavelengths (514, 633 and 785 nm) to tune the Raman signals. Enhancement factors of the SHINERS assembly have been estimated and compared to the SERS effect of unmodified silver NPs colloidal dispersions. Finally, the grafting of the copper(ii) complex onto Ag@TiO2 was advantageously compared to the grafting onto Ag@SiO2 shell. [ABSTRACT FROM AUTHOR]

This paper demonstrates the use of surface plasmon resonance of core-shell Ag@TiO2 particles in SHINERS experiments. A copper(ii) complex grafted onto Ag@TiO2 surface was probed by Raman spectroscopy using resonance excitation profiles vs. excitation wavelengths (514, 633 and 785 nm) to tune the Raman signals. Enhancement factors of the SHINERS assembly have been estimated and compared to the SERS effect of unmodified silver NPs colloidal dispersions. Finally, the grafting of the copper(ii) complex onto Ag@TiO2 was advantageously compared to the grafting onto Ag@SiO2 shell.

Background: The aim of this retrospective study was to evaluate the contribution of fluorine-18-fluoro-deoxyglucose (FDG) positron emission tomography (PET) to the clinical management and survival outcome of patients (pts) suspected of recurrent ovarian carcinoma, with the hypothesis that early diagnosis of recurrent ovarian cancer may improve overall survival (OS)., Methods: Fifty-three FDG PET/CT scans were retrospectively analyzed for 42 pts. CT and PET/CT findings were confirmed by imaging and clinical follow-up, and/or pathology, which were considered as the gold standard diagnosis. The treatment plan based on CT staging was compared with that based on PET/CT findings. Medical records were reviewed for pts characteristics, progression-free survival (PFS), and OS. PFS and OS were analyzed using the Cox proportional hazards regression model., Results: The final diagnosis of recurrence was established pathologically (n = 16), or by a median clinical follow-up of 6.5 years (range 0.5-7.5) after the PET/CT (n = 37). PET/CT provided a higher detection sensitivity (92.2%, 47/51) than CT (60.8%, 31/51) (p < 0.001). Globally, PET/CT modified the treatment plan in 56.6% (30/53) and in 65.2% (15/23) when the CT was negative prior to PET/CT. In 30 cases, those benefited from a modified treatment plan, these changes led to the intensification of a previous treatment procedure in 83.3% (25/30), and to a reduction in the previous treatment procedure in 16.6% of cases (5/30). The Cox regression multivariate analysis showed that the number of lesions visualized by CT and presence of lung lesions detected by PET/CT were significantly associated with PFS (p = 0.002 and p = 0.035, respectively)., Conclusion: On account of its impact on treatment planning, and especially in predicting patient outcome, FDG PET is a valuable diagnostic tool for cases of suspected ovarian cancer recurrence.