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• A workflow to model and design bilayered and conformal scaffolds was proposed. • Lattices with full connectivity and uniform cell size were generated. • The procedure allows maximizing the scaffold osteointegration/vascularization. A fundamental outcome of bone tissue engineering is the regeneration of bone defects presenting large dimensions. A promising solution in biomedical practice is the implantation of biomimetic scaffolds, i.e. porous structures mimicking the natural shapes of healthy bone tissues, which are colonized by mesenchymal stem cells and that support the growth of the regenerating tissues, until the complete healing process is realized. This work presented a workflow for the geometrical modeling and the mechanical design of beam-based, bilayered, and conformal scaffolds, mimicking the human cortico-cancellous bone structure for filling a large dimension defect in the mandibular bone of an injured patient. An isotropic Voronoi topology built on a refined point set generated by a high-quality meshing algorithm was adopted for lattice generation, which led to an open-cell architecture characterized by full connectivity and uniform cell size. Such geometrical and structural features represent crucially important requirements for maximizing the osteointegration and the vascularization of the implanted scaffold. An irregular scaffold was modelled, including a cortical and a sponge layer. The beam radii of both layers were determined by matching the elastic properties of the corresponding bone tissues, thus minimizing the stress shielding effects. Interestingly, several scaffold properties deriving from the proposed procedure, such as the porosity and the pore size, were in good agreement with those reported in the literature. [ABSTRACT FROM AUTHOR]

One of the most effective strategies that can be adopted to make successful cultural heritage expositions consists in attracting the visitors’ attention and improving their enjoyment/engagement. A mid-air gesture-based Natural User Interface was designed, through the user-centric approach, for the navigation of virtual tours in cultural heritage exhibitions. In detail, the proposed interface was developed to “visit” Murgia, a karst zone lying within Puglia, very famous for its fortified farms, dolines, sinkholes, and caves. Including an “immersive” gesture-based interface was demonstrated to improve the user's experience thus giving her/him the sensation of “exploring” in a seamless manner the wonderful and rather adventurous sites of Murgia. User tests aimed at comparing the implemented interface with a conventional mouse-controlled one confirmed the capability of the proposed interface to enhance the user engagement/enjoyment and to make “more” natural/real, the virtual environment. [ABSTRACT FROM AUTHOR]

Augmented reality (AR) is a key technology for the development of smart manufacturing. One of the main advantages of AR is that it can help workers to accomplish several tasks, making it possible the shift from mass production to mass customization. However, it is still not clear how these promises can be fulfilled in an industrial scenario. In particular, the question about which display solutions fit better the industrial constraints remains open. Based on the literature overview, laboratory experiments, and feedbacks from industrial companies, we supported the use of spatial augmented reality (SAR), designing a prototype intended to be used for manual working stations of the future smart factories. This work presents the evaluation of the effectiveness of conveying technical instructions with this SAR prototype as compared to paper manual. We run a within-subjects experiment with 16 participants to measure user task performance (completion times and error rates) and to collect subjective evaluation. We projected technical information on a motorbike engine during a seven-task maintenance procedure. Our results proved that SAR technology improves the operators' performance with respect to a paper manual and that users well accept it. We found that SAR is more effective for difficult tasks than for simple ones and that the main advantage of SAR is related more to the reduction of error rates than to completion times. These results confirm the goodness of our design choices; then our prototype can be a valid candidate solution for a smart manufacturing application. [ABSTRACT FROM AUTHOR]

The evaluation of the exposure to risk factors in workplaces and their subsequent redesign represent one of the practices to lessen the frequency of work-related musculoskeletal disorders. In this paper we present K2RULA, a semi-automatic RULA evaluation software based on the Microsoft Kinect v2 depth camera, aimed at detecting awkward postures in real time, but also in off-line analysis. We validated our tool with two experiments. In the first one, we compared the K2RULA grand-scores with those obtained with a reference optical motion capture system and we found a statistical perfect match according to the Landis and Koch scale (proportion agreement index = 0.97, k = 0.87). In the second experiment, we evaluated the agreement of the grand-scores returned by the proposed application with those obtained by a RULA expert rater, finding again a statistical perfect match (proportion agreement index = 0.96, k = 0.84), whereas a commercial software based on Kinect v1 sensor showed a lower agreement (proportion agreement index = 0.82, k = 0.34). [ABSTRACT FROM AUTHOR]

Functionally Graded Scaffolds (FGSs) are porous biomaterials where porosity changes in space with a specific gradient. In spite of their wide use in bone tissue engineering, possible models that relate the scaffold gradient to the mechanical and biological requirements for the regeneration of the bony tissue are currently missing. In this study we attempt to bridge the gap by developing a mechanobiology-based optimization algorithm aimed to determine the optimal graded porosity distribution in FGSs. The algorithm combines the parametric finite element model of a FGS, a computational mechano-regulation model and a numerical optimization routine. For assigned boundary and loading conditions, the algorithm builds iteratively different scaffold geometry configurations with different porosity distributions until the best microstructure geometry is reached, i.e. the geometry that allows the amount of bone formation to be maximized. We tested different porosity distribution laws, loading conditions and scaffold Young’s modulus values. For each combination of these variables, the explicit equation of the porosity distribution law–i.e the law that describes the pore dimensions in function of the spatial coordinates–was determined that allows the highest amounts of bone to be generated. The results show that the loading conditions affect significantly the optimal porosity distribution. For a pure compression loading, it was found that the pore dimensions are almost constant throughout the entire scaffold and using a FGS allows the formation of amounts of bone slightly larger than those obtainable with a homogeneous porosity scaffold. For a pure shear loading, instead, FGSs allow to significantly increase the bone formation compared to a homogeneous porosity scaffolds. Although experimental data is still necessary to properly relate the mechanical/biological environment to the scaffold microstructure, this model represents an important step towards optimizing geometry of functionally graded scaffolds based on mechanobiological criteria. [ABSTRACT FROM AUTHOR]

In the Industrie 4.0 vision, the creation of leading-edge options for interaction between people and technology occupies a key role. In this context, augmented reality (AR) is one of the most suitable solutions. However, it is still not ready to be effectively used in industry. A crucial problem is the legibility of text seen through AR head-worn displays (HWDs). AR interface designers have no standard guidelines to follow, especially for these devices. Literature and anecdotal evidence suggest that legibility depends mainly on background, display technology (that is, see-through optical or video HWDs), and text style (for example, plain text, outline, or billboard). Furthermore, there are constraints to consider in industrial environments, such as standard color-coding practices and workplace lighting. The authors examine aspects affecting text legibility with an emphasis on deriving guidelines to support AR interface designers. Their results suggest that enhancing text contrast via software, along with using the outline or billboard style, is an effective practice to improve legibility in many situations. If one text style is needed for both types of HWD, their results suggest that colored billboards (with neutral white text) are effective. When color coding is not mandatory, white text and blue billboard are more effective than other styles tested. [ABSTRACT FROM PUBLISHER]

Abstract: People vaccinated against influenza develop hemagglutination inhibition (HAI) antibodies (Ab) that bind to the virus and neutralize it. Ab titer levels are variable depending on factors insufficiently studied, and tend to decrease over time. In the present study, we analyzed antibodies responses before and after influenza vaccination in nurses working in a hospital, with the aim of: [-] identifying seroconversion rates to trivalent influenza vaccine one month after immunization; [-] evaluating if, six months after vaccination, influenza HAI Ab titer fall comparing to one-month post vaccination HAI Ab titer; [-] studying the association between the lack of HAI Ab response (seroconversion) assessed one month after immunization and: [∘] past influenza vaccinations, [∘] baseline (before vaccination) HAI Ab titer, [∘] baseline (before vaccination) HAI Ab titer≥40 (considered as a protection titer). Hemagglutination inhibition reaction was used to assess specific HAI Ab titers against influenza A(H1N1), A(H3N2) and B virus strains included in the influenza vaccine and we used progressive dilutions of two times, starting on 1:10 until 1:20.480. Seroconversion rates, one month after vaccination, were 66.7% for A(H1N1) strain, 63.2% for A(H3N2) strain and 56.3% for B strain. The most immunogenic strain used in 2007/08 influenza vaccine was A(H1N1). Seroconversion rates after one month were negatively associated with past influenza vaccinations, baseline HAI Ab titers≥40 and baseline HAI Ab titers. Six months after vaccination, 50% of participants showed a drop in HAI Ab titers to an half, for each of the considered strains, but they remain high enough to protect against the disease. [Copyright &y& Elsevier]

Tumor necrosis factor receptor-associated factor (TRAF) proteins are cytoplasmic regulatory molecules that function as signal transducers for receptors involved in both innate and adaptive humoral immune responses. In this study, we show that TRAF7, the unique noncanonical member of the TRAF family, physically associates with IκB kinase/NF-κB essential modulator (NEMO) and with the RelA/p65 (p65) member of the NF-κB transcription factor family. TRAF7 promotes Lys-29-linked polyubiquitination of NEMO and p65 that results in lysosomal degradation of both proteins and altered activation. TRAF7 also influences p65 nuclear distribution. Microarray expression data are consistent with an inhibitory role for TRAF7 on NF-κB and a positive control of AP-1 transcription factor. Finally, functional data indicate that TRAF7 promotes cell death. Thus, this study identifies TRAF7 as a NEMO- and p65-interacting molecule and brings important information on the ubiquitination events that control NF-κB transcriptional activity. [ABSTRACT FROM AUTHOR]

The procedure commonly adopted to characterize cell materials using atomic force microscopy neglects the stress state induced in the cell by the adhesion structures that anchor it to the substrate. In several studies, the cell is considered as made from a single material and no specific information is provided regarding the mechanical properties of subcellular components. Here we present an optimization algorithm to determine separately the material properties of subcellular components of mesenchymal stem cells subjected to nanoindentation measurements. We assess how these properties change if the adhesion structures at the cell-substrate interface are considered or not in the algorithm. In particular, among the adhesion structures, the focal adhesions and the stress fibers were simulated. We found that neglecting the adhesion structures leads to underestimate the cell mechanical properties thus making errors up to 15%. This result leads us to conclude that the action of adhesion structures should be taken into account in nanoindentation measurements especially for cells that include a large number of adhesions to the substrate. [ABSTRACT FROM AUTHOR]

In a context more and more oriented towards customized medical solutions, we propose a mechanobiology-driven algorithm to determine the optimal geometry of scaffolds for bone regeneration that is the most suited to specific boundary and loading conditions. In spite of the huge number of articles investigating different unit cells for porous biomaterials, no studies are reported in the literature that optimize the geometric parameters of such unit cells based on mechanobiological criteria. Parametric finite element models of scaffolds with rhombicuboctahedron unit cell were developed and incorporated into an optimization algorithm that combines them with a computational mechanobiological model. The algorithm perturbs iteratively the geometry of the unit cell until the best scaffold geometry is identified, i.e. the geometry that allows to maximize the formation of bone. Performances of scaffolds with rhombicuboctahedron unit cell were compared with those of other scaffolds with hexahedron unit cells. We found that scaffolds with rhombicuboctahedron unit cell are particularly suited for supporting medium-low loads, while, for higher loads, scaffolds with hexahedron unit cells are preferable. The proposed algorithm can guide the orthopaedic/surgeon in the choice of the best scaffold to be implanted in a patient-specific anatomic region. [ABSTRACT FROM AUTHOR]

• Design and development of an immersive VR system for confined space safety training. • Use of the Kirkpatrick model for experimental validation of platform effectiveness. • Excellent user experience of VR system, enhancing engagement and knowledge transfer. • Positive impact on operators' safety behaviors, reducing execution times and errors. Safety in the industrial sector is paramount, with national legislations establishing specific regulations to reduce accidents. These regulations emphasize risk removal and proper operator training as preventive measures. However, traditional training can be time-consuming and costly, leading companies to meet only the minimum requirements. In particular, confined spaces pose significant dangers, often resulting in fatal, cascading accidents due to a lack of proper safety procedures. Therefore, effective training is crucial to mitigate these risks. Advanced technologies like Immersive Virtual Reality (IVR) present new opportunities for cost-effective and extensive training campaigns by eliminating the risks associated with real environment training, offering a safe yet realistic experience. Despite the widespread adoption of IVR training applications in industrial research, there is a notable lack of systematic approaches to evaluate their effectiveness. Conducting such evaluations is crucial to ascertain their impact on essential training outcomes, including participant engagement, knowledge transfer, and enhanced safety behavior during work activities. To address this gap, we developed an IVR-based training platform for confined space safety procedures and established a systematic validation procedure using the Kirkpatrick model to assess its effectiveness compared to conventional training methods. Results demonstrate that IVR training provides an excellent user experience, better knowledge transfer than the traditional approach, and improved performance in simulated procedures, reducing execution errors and completion times. This dual focus on creating and validating the IVR system underscores its potential as an effective training tool in hazardous environments such as confined spaces, where proper training can prevent tragic fatalities. [ABSTRACT FROM AUTHOR]

The application of augmented reality in industrial environments requires an effective visualization of text on a see-through head-mounted display (HMD). The main contribution of this work is an empirical study of text styles as viewed through a monocular optical see-through display on three real workshop backgrounds, examining four colors and four different text styles. We ran 2,520 test trials with 14 participants using a mixed design and evaluated completion time and error rates. We found that both presentation mode and background influence the readability of text, but there is no interaction effect between these two variables. Another interesting aspect is that the presentation mode differentially influences completion time and error rate. The present study allows us to draw some guidelines for an effective use of AR text visualization in industrial environments. We suggest maximum contrast when reading time is important, and the use of colors to reduce errors. We also recommend a colored billboard with transparent text where colors have a specific meaning. [ABSTRACT FROM AUTHOR]

Style sketches are an essential tool for the expression and the definition of the shape of industrial products. We present a novel wavelet approach for sketch segmentation and editing expressly addressed to the designer needs. Starting from a 2D curve drawn by a user with a graphics tablet, our algorithm converts it in a B-spline representation, detects the style features, allows interactive smoothing and continuous local and global editing. The novelty compared to the existing literature is the combination of: (i) unified wavelet approach to segmentation, smoothing and editing, (ii) support for endpoint C0 and C1 continuity constraints and (iii) implementation with an interactive pen-tablet interface. Our approach requires low memory footprints with time complexity linear in the number of control points. We validated the algorithm with synthetic and practical tests. [ABSTRACT FROM AUTHOR]

This work investigates the possibility of using a novel "minimal AR" authoring approach to optimize the visual assets used in augmented reality (AR) interfaces to convey work instructions in manufacturing. In the literature, there are no widely supported guidelines for the optimal choice of visual assets (e.g., CAD models, drawings, and videos). Therefore, to avoid the risk of having AR technical documentation based only on the author's preference, our work proposes a novel authoring approach that enforces the minimal amount of information to accomplish a task. Minimal AR was tested through a simulated AR LEGO-based assembly task. The performance (completion time, mental workload, errors) of 40 users was evaluated with 4 combinations of visual assets in 4 tasks with an increasing amount of information needed. The main result is that visual assets with an excess of information do not significantly increase performance. Therefore, the location of a specified object should be "minimally" authored by an auxiliary model (e.g., a circle and an arrow). For identifying an object within a couple, color coding is preferred to using additional visual assets. If more than two objects must be identified, a drawing visual asset is also needed. Only when the orientation of a selected object must be conveyed, animated product models are required. These insights could be helpful for an optimal design of AR work instructions in a wide range of industrial fields. [ABSTRACT FROM AUTHOR]

The effects of different dietary proteins on the progression of a focal atheromatous lesion and on lipoprotein oxidiability were studied in male New Zealand rabbits. Focal lesions were induced on common carotid arteries by applying an electric current, using a bipolar microcoagulator. After surgery, animals were fed for 90 days two different diets, both with 1% cholesterol, 15% saturated fatty acids and 20% protein: the protein source was constituted in one group (SOY) by 16% soy protein isolate plus 4% milk whey proteins, in the other (CASEIN) by 16% casein plus 4% milk whey proteins. Lower levels of plasma cholesterol and triglycerides (−47 and −65%, respectively) (P<0.05) were detected in the SOY versus the CASEIN group at the end of treatment. Cryosection analyses of the carotids, indicated a highly significant reduction (−39%; P<0.05) in the focal lesion progression in the SOY versus the CASEIN group. Copper-mediated oxidation of low-density lipoprotein (LDL) from rabbits fed the two different diets, performed in vitro by analysis of conjugated diene formation, showed a significantly longer lag phase in the SOY (150±5 min) versus the CASEIN animals (20±3 min) (P<0.05). These data, while confirming the well-known lipid lowering properties of soy proteins, indicate, in this animal model, a remarkable activity on a focal atheromatous lesion, possibly also linked to a powerful antioxidant activity. [Copyright &y& Elsevier]

This study investigates the use of augmented reality technology (AR) in the field of maritime navigation and how researchers and designers have addressed AR data visualisation. The paper presents a systematic review analysing the publication type, the AR device, which information elements are visualised and how, the validation method and technological readiness. Eleven AR maritime solutions identified from scientific papers are studied and discussed in relation to previous navigation tools. It is found that primitive information such as course, compass degrees, boat speed and geographic coordinates continue to be fundamental information to be represented even with AR maritime solutions. [ABSTRACT FROM AUTHOR]

Despite the wide use of scaffolds with spherical pores in the clinical context, no studies are reported in the literature that optimize the micro-architecture dimensions of such scaffolds to maximize the amounts of neo-formed bone. In this study, a mechanobiology-based optimization algorithm was implemented to determine the optimal geometry of scaffolds with spherical pores subjected to both compression and shear loading. We found that these scaffolds are particularly suited to bear shear loads; the amounts of bone predicted to form for this load type are, in fact, larger than those predicted in other scaffold geometries. Knowing the anthropometric characteristics of the patient, one can hypothesize the possible value of load acting on the scaffold that will be implanted and, through the proposed algorithm, determine the optimal dimensions of the scaffold that favor the formation of the largest amounts of bone. The proposed algorithm can guide and support the surgeon in the choice of a "personalized" scaffold that better suits the anthropometric characteristics of the patient, thus allowing to achieve a successful follow-up in the shortest possible time. [ABSTRACT FROM AUTHOR]

Schizophrenia poses a significant economic burden on the healthcare system as well as it has a significant impact on society at large. Reasons for such a high economic burden of schizophrenia include the frequent relapses and hospitalizations occurring in this disorder. We analyze the effectiveness of long-acting injectable antipsychotics (LAIs) compared to oral medications, in terms of "clinical process management" in a sample of patients with a diagnosis of schizophrenia spectrum disorder treated in community mental health centers. An observational, retrospective, mirror-image study was carried out to evaluate the effectiveness of LAIs compared to oral medications in terms of number of hospitalizations, emergency visits and planned visits on a 10-year period (from July 2007 to June 2017). Differences between first and second generation LAIs were also explored. Our findings show that hospitalization and emergency visits are significantly decreased with the use of LAIs, while planned visits are increased in patients treated with LAIs. Our results suggest that LAIs, in particular, second generation ones, reduce hospitalization rates and emergency visits, improving the economic burden of schizophrenia. Therefore, LAIs should be considered a cost-effective treatment in the management of schizophrenia under routine conditions. [ABSTRACT FROM AUTHOR]

This article explores what it takes to make interactive computer graphics and VR attractive as a promotional vehicle, from the points of view of tourism agencies and the tourists themselves. The authors exploited current VR and human-machine interface (HMI) technologies to develop an interactive, innovative, and attractive user experience called the Multisensory Apulia Touristic Experience (MATE). The MATE system implements a natural gesture-based interface and multisensory stimuli, including visuals, audio, smells, and climate effects. [ABSTRACT FROM AUTHOR]

Text legibility in augmented reality with optical see-through displays can be challenging due to the interaction with the texture on the background. Literature presents several approaches to predict legibility of text superimposed over a specific image, but their validation with an AR display and with images taken from the industrial domain is scarce. In this work, we propose novel indices extracted from the background images, displayed on an LCD screen, and we compare them with those proposed in literature designing a specific user test. We collected the legibility user ratings by displaying white text over 13 industrial background images to 19 subjects using an optical see-through head-worn display. We found that most of the proposed indices have a significant correlation with user ratings. The main result of this work is that some of the novel indices proposed had a better correlation than those used before in the literature to predict legibility. Our results prove that industrial AR developers can effectively predict text legibility by simply running image analysis on the background image. [ABSTRACT FROM AUTHOR]

Naringenin has been shown to exert antiestrogenic, cholesterol-lowering and antioxidant activities, as well as an indirect modulation on the metabolism of many xenobiotics. It is one of the most abundant polyphenols in tomato. Given the widespread consumption of tomato (Lycopersicum esculentum) and tomato-based products, this study was designed to determine whether plasma levels of naringenin were detectable in five men after consumption of a test meal containing 150 mg of cooked tomato paste. Naringenin intake with the test meal was 3.8 mg. Blood was drawn from fasting subjects and 2, 4, 6, 8 and 24 h after the meal. To compare the results with a control, the same meal without tomato paste (control meal) was administered to the same subjects 2 wk later. Analyses were performed using high-performance liquid chromatography coupled with a CoulArray electrochemical detector. The peak plasma concentration was 0.12 +/- 0.03 micro mol/L 2 h after the meal. Unconjugated naringenin was not detected. Naringenin was not detected in plasma at any time after consumption of the control meal. In addition to naringenin, we detected rutin and chlorogenic acid in tomato paste, but these polyphenols and their derivatives (quercetin and caffeic acid) were not detected in plasma at any time. To the best of our knowledge, this is the first study demonstrating naringenin bioavailability in humans after consumption of a meal containing cooked tomato paste. [ABSTRACT FROM AUTHOR]

Since its beginning at the end of 2019, the pandemic spread of the severe acute respiratory syndrome coronavirus 2 (Sars-CoV-2) caused more than one million deaths in only nine months. The threat of emerging and re-emerging infectious diseases exists as an imminent threat to human health. It is essential to implement adequate hygiene best practices to break the contagion chain and enhance society preparedness for such critical scenarios and understand the relevance of each disease transmission route. As the unconscious hand–face contact gesture constitutes a potential pathway of contagion, in this paper, the authors present a prototype system based on low-cost depth sensors able to monitor in real-time the attitude towards such a habit. The system records people's behavior to enhance their awareness by providing real-time warnings, providing for statistical reports for designing proper hygiene solutions, and better understanding the role of such route of contagion. A preliminary validation study measured an overall accuracy of 91%. A Cohen's Kappa equal to 0.876 supports rejecting the hypothesis that such accuracy is accidental. Low-cost body tracking technologies can effectively support monitoring compliance with hygiene best practices and training people in real-time. By collecting data and analyzing them with respect to people categories and contagion statistics, it could be possible to understand the importance of this contagion pathway and identify for which people category such a behavioral attitude constitutes a significant risk. [ABSTRACT FROM AUTHOR]