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Abstract Freiberg disease is a rare condition whose diagnosis requires a high clinical suspicion. Avascular necrosis of the metatarsal head progresses with articular collapse, leading to forefoot pain and limitation of the daily activities. Several surgical techniques have been described to address the disease, and since it is usually diagnosed in later-stages, most of them include joint-destructive procedures. The use of arthroscopy on the small joint of the foot has arisen in the last few years, but its application in Freiberg disease is still scant. Joint-preserving procedures have been advocated for cases of early-stage disease, aiming to relieve symptoms while preventing the progression of the disease. In the present report, we describe a successful treatment of a 12-year-old patient with early-stage Freiberg disease using core decompression and bone marrow graft through a minimally-invasive approach assisted by arthroscopy.

The usage of bio-fibres and recycled materials is a growing approach to address the ecological problems being faced today. Inspired by the guidelines defining the Waste for Life initiative, the present study reports new composite materials, based on the recycling of high-impact polystyrene, found, for instance in yogurt cups, and paper plastic laminates, deriving from disposable paper cups. Given their recycling incompatibility, paper plastic laminates are either dumped in landfills or incinerated after their first usage, threatening the environmental condition. Therefore, through the development of a new composite solution, the goal was to reduce this damaging environmental impact by providing a second life to both paper plastic laminates and high-impact polystyrene. Samples presented overall good mechanical properties, from which it is highlighted a Young’s Modulus of 1.75 GPa and a Tensile Strength of 21.2 MPa, encouraging the application of the present material to identified global obstacles.

Abstract We present a unified model where the same scalar field can drive inflation and account for the present dark matter abundance. This scenario is based on the incomplete decay of the inflaton field into right-handed neutrino pairs, which is accomplished by imposing a discrete interchange symmetry on the inflaton and on two of the right-handed neutrinos. We show that this can lead to a successful reheating of the Universe after inflation, while leaving a stable inflaton remnant at late times. This remnant may be in the form of WIMP-like inflaton particles or of an oscillating inflaton condensate, depending on whether or not the latter evaporates and reaches thermal equilibrium with the cosmic plasma. We further show that this scenario is compatible with generating light neutrino masses and mixings through the seesaw mechanism, predicting at least one massless neutrino, and also the observed baryon asymmetry via thermal leptogenesis.

Bone is an outstanding, well-designed composite. It is constituted by a multi-level structure wherein its properties and behavior are dependent on its composition and structural organization at different length scales. The combination of unique mechanical properties with adaptive and self-healing abilities makes bone an innovative model for the future design of synthetic biomimetic composites with improved performance in bone repair and regeneration. However, the relation between structure and properties in bone is very complex. In this review article, we intend to describe the hierarchical organization of bone on progressively greater scales and present the basic concepts that are fundamental to understanding the arrangement-based mechanical properties at each length scale and their influence on bone’s overall structural behavior. The need for a better understanding of bone’s intricate composite structure is also highlighted.

Aim: The purpose of this systematic literature review is to check papers to find the best method for measuring association between health interventions and productivity and find best intervention in workplace for increasing productivity. Method: This systematic review was performed based on PRISMA statement methodology and performed on all papers about association between productivity with intervention for increasing physical activity, published from 2007 until June 2017. The search was limited to English language items. Conclusion: The results of this systematic review demonstrate that providing interventions for workers in various workplaces have a low to high affecting on productivity, as measured by objective and organization specific metrics or subjective and self-report questionnaires. The Analyze of result showed that using different methods simultaneously can make more accuracy and precision. Also it’s better that before filling the self-report questionnaires researchers train all workers about the purpose of the study.

Musculoskeletal disorders are becoming an ever-growing societal burden and, as a result, millions of bone replacements surgeries are performed per year worldwide. Despite total joint replacements being recognized among the most successful surgeries of the last century, implant failure rates exceeding 10% are still reported. These numbers highlight the necessity of technologies to provide an accurate monitoring of the bone−implant interface state. This study provides a detailed review of the most relevant methodologies and technologies already proposed to monitor the loosening states of endoprosthetic implants, as well as their performance and experimental validation. A total of forty-two papers describing both intracorporeal and extracorporeal technologies for cemented or cementless fixation were thoroughly analyzed. Thirty-eight technologies were identified, which are categorized into five methodologies: vibrometric, acoustic, bioelectric impedance, magnetic induction, and strain. Research efforts were mainly focused on vibrometric and acoustic technologies. Differently, approaches based on bioelectric impedance, magnetic induction and strain have been less explored. Although most technologies are noninvasive and are able to monitor different loosening stages of endoprosthetic implants, they are not able to provide effective monitoring during daily living of patients.

The use of fiber reinforced plastics has increased in the last decades due to their unique properties. Advantages of their use are related with low weight, high strength and stiffness. Drilling of composite plates can be carried out in conventional machinery with some adaptations. However, the presence of typical defects like delamination can affect mechanical properties of produced parts. In this paper delamination influence in bearing stress of drilled hybrid carbon+glass/epoxy quasi-isotropic plates is studied by using image processing and analysis techniques. Results from bearing test show that damage minimization is an important mean to improve mechanical properties of the joint area of the plate. The appropriateness of the image processing and analysis techniques used in the measurement of the damaged area is demonstrated.

ABSTRACT Synovial chondromatosis is a rare proliferative disease, characterized by the occurrence of metaplasia in the synovium of the joints. These lesions become pedunculated; with the evolution of the disease they become detached, leading to intra-articular loose-bodies. It occurs more frequently in males between the third and fifth decades of life, usually affecting large joints such as the knee and hip. Smaller joints, such as the ankle, are less frequently affected. Patients report articular pain, blockage, and limited range of motion caused by the loose fragments. As the disease progresses, the joint undergoes degenerative changes. This report describes a case of synovial chondromatosis of the ankle, treated by arthroscopy. The patient, a 59 year-old male, complained of pain and swelling of the left ankle. Physical evaluation showed limited tibiotarsal mobility (plantar flexion of 20° and dorsiflexion of 5°). After physical and imaging evaluation, the patient underwent ankle arthroscopy due to impingement of the joint, with limitation of mobility. Arthroscopic treatment allowed easy access to the joint, removal of loose bodies, and partial synovectomy, with low morbidity and early rehabilitation. The final prognosis was excellent.

This paper presents a mesoscale damage model for composite materials and its validation at the coupon level by predicting scaling effects in un-notched carbon-fiber reinforced polymer (CFRP) laminates. The proposed material model presents a revised longitudinal damage law that accounts for the effect of complex 3D stress states in the prediction of onset and broadening of longitudinal compressive failure mechanisms. To predict transverse failure mechanisms of unidirectional CFRPs, this model was then combined with a 3D frictional smeared crack model. The complete mesoscale damage model was implemented in ABAQUS®/Explicit. Intralaminar damage onset and propagation were predicted using solid elements, and in-situ properties were included using different material cards according to the position and effective thickness of the plies. Delamination was captured using cohesive elements. To validate the implemented damage model, the analysis of size effects in quasi-isotropic un-notched coupons under tensile and compressive loading was compared with the test data available in the literature. Two types of scaling were addressed: sublaminate-level scaling, obtained by the repetition of the sublaminate stacking sequence, and ply-level scaling, realized by changing the effective thickness of each ply block. Validation was successfully completed as the obtained results were in agreement with the experimental findings, having an acceptable deviation from the mean experimental values. [ABSTRACT FROM AUTHOR]

La supervivencia de la tortuga verde y su éxito reproductivo resultan obstaculizados por múltiples factores durante todo su ciclo de vida. La etapa reproductiva, en particular, es un proceso de muy alto riesgo. Las características y la influencia del hombre en las diferentes etapas del ciclo reproductivo, constituyen incógnitas importantes. La aplicación de métodos de estimación de riesgo puede contribuir al conocimiento de los principales factores que afectan el ciclo reproductivo de las tortugas y cuáles pueden ser manejados con la finalidad de prever, controlar o mitigar dichos riesgos. El método de matriz de riesgo tridimensional puede contribuir a un análisis detallado por su carácter descriptivo de secuencias accidentales, así como un análisis semicuantitativo en la estimación del riesgo. El estudio permitió identificar 25 secuencias de fallo del ciclo distribuidas en cinco etapas. El balance de riesgos aporta dos riesgos muy altos y nueve riesgos altos para el ciclo de vida de estos quelonios. Se demuestra la influencia preponderante de factores humanos en los riesgos resultantes de la depredación y la contaminación del hábitat a lo largo de su ciclo de vida. Las defensas más efectivas para el control de los riesgos están relacionadas con mecanismos naturales de sobrevivencia de la especie mientras las medidas de protección implementadas por el hombre tienen poco impacto en la salvaguarda del ciclo reproductivo de las tortugas. La incorporación al patrón de riesgo modelado de mecanismos naturales de sobrevivencia, en forma de defensas constituye una novedad que permite extender el método al estudio de riesgo de otros ciclos naturales.

Highlights: • This study proposes the practical utility of an immersive Virtual Reality (VR) experience for the dissemination and study of Palaeolithic Rock Art. • Thanks to a series of multidisciplinary studies, a virtual reconstruction of the archaeological context of an area with rock art has been achieved. • The Palaeolithic lighting systems documented in Atxurra cave have been virtually recreated, allowing real-time interaction through VR. Abstract: The Upper Palaeolithic period (ca. 45000 - 12000 BP) was the time when figurative art chiefly produced by Homo sapiens emerged and developed. The Upper Palaeolithic rock art entails a multisensory experience that goes beyond depicted images observation: it includes aspects related to the cognitive development of human mind, the spatial dimensions, the type of rock surface, artificial lighting, and challenges of navigating the underground environment. Traditionally, the study of Palaeolithic art in caves has focused on paintings and illustrated subjects' graphic analysis. However, a recent shift in methodological focus has favoured a comprehensive and interdisciplinary study of rock art. This new perspective has allowed the investigation of surrounding elements that significantly influence the art and its interpretation. Combining this with new digital technologies, it is now possible to reconstruct Palaeolithic artistic creation and contemplation environments with precision, offering researchers an immersive and interactive experience through virtual reality (VR). The two documented Palaeolithic lighting systems in the sector J “Ledge of the Horses” have been virtually recreated. The lighting simulation parameters are based on those obtained from an anthracological study of the charcoal remains found in the cave and the subsequent experimental program. The study included analysing both three-dimensional (3D) models of the cave, obtained through photogrammetry and laser scanning, and the lighting systems in the graphics engine ©Unreal Engine 5; this allowed the researchers to create an interactive VR environment that faithfully reflects the current state of scientific knowledge about the cavity. Using VR is a substantial methodological advancement, regarding both knowledge transmission and the creation of more robust and coherent archaeological interpretations through sensory perception and historical empathy. This approach has been applied to the main decorated sector of the Atxurra Cave (Basque Country, Spain), a space containing dozens of engraved and painted representations, and surface archaeological material, subjected to a comprehensive multidisciplinary study.