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Although isometric contractions in human muscles have been analyzed several times, there are no FEA models that allow us to use the same modeled joint (the elbow under our case) in different conditions. Most elbow joints use 3D elements for meshing. Representing the muscles in the joint is quite useful when the study is focused on the muscle itself, knowing stress distribution on muscle, and checking damage in muscle in a detailed manner (tendon–muscle insertion, for example). However, this technique is not useful for studying muscle behavior at different positions of the joint. This study, based on the mechanical model of the elbow joint, proposes a methodology for modelling muscles that will be studied in different positions by meshing them with 1D elements. Furthermore, the methodology allows us to calculate biceps and triceps efforts under load for different angles of elbow joint aperture. The simulation results have been mathematically modelled to obtain general formulations for these efforts, depending on the load and the aperture angle. [ABSTRACT FROM AUTHOR]

Norbert Elias is an author traditionally absent in communication studies. His relevance for this field has begun to be defended recently, an argumentative line with which this paper is also identified. The article has two interrelated aims. First, present the main dimensions of Norbert Elias' analysis on human communication. Second, critically examine several current studiesthat, in communication studies, take this author as a theoretical reference for their research. To achieve the first aim, it is analysed Theory of the Symbol, a book originally published in 1989, where Elias collects his reflections about the communicational and symbolic dimensions of human being. To achieve the second goal, the paper is focused on the concept of Communicative Figuration, recently developed according to an eliasian perspective, and currently applied in several studies devoted to the topic of mediatization. [ABSTRACT FROM AUTHOR]

In 2011, Portugal launched a residence permit programme to attract foreign investment from non‐EU citizens, with Chinese business migrants representing those taking most advantage of this initiative. This paper analyses this policy measure and assesses its social consequences, as a new way that Chinese migrants have to enter Portugal. Firstly, we characterise this programme by identifying its principles and legal requirements, using official data from 2012 to 2018. We then describe the emergence of this type of residence permit as a response to the financial crisis of 2011, and as part of a neoliberal political rationality that has guided a governance model since this time. Next, we characterise the profile of Chinese citizens who benefit from this initiative and claim residence permits on the basis of their economic power. Finally, we discuss the social and political implications of this kind of entrance to Portugal, to provide some insights for policymakers. [ABSTRACT FROM AUTHOR]

The creation of new rapid prototyping techniques, low cost 3D printers as well as the creation of new software for these techniques have allowed the creation of 3D models of bones making their application possible in the field of teaching anatomy in the faculties of Health Sciences. The 3D model of cranium created in the present work, at full scale, present accurate reliefs and anatomical details that are easily identifiable by undergraduate students in their use for the study of human anatomy. In this article, the process of scanning the skull and the subsequent treatment of these images with specific software until the generation of 3D model using 3D printer has been reported. [ABSTRACT FROM AUTHOR]

Purpose The purpose of this paper is to present a solution for the levelling plate of fused deposition modelling (FDM) additive manufacturing (AM) systems. This automatic levelling system is presented as an evolution of actual systems, which uses a new ultrasound sensing system.Design/methodology/approach After obtaining a prototype, different tests were conducted for getting a system which solves the level plate problem and can be mounted in any FDM AM machine. Several benchmark models were obtained and compared with current equipment concepts for the validity of the product.Findings All tests were performed with high accuracy, enabling the production of geometries that could not have been achieved without this novel system.Practical implications This development will enable experienced users to set aside the problems of calibration and focus on the purpose of this type of machines, making prototypes.Originality/value A system architecture has been developed and integrated into an open hardware AM system, allowing real-time adjustment of the plate during each layer, thus eliminating the need of levelling the plate, allowing to achieve easier printing, and without increasing the cost significantly. [ABSTRACT FROM AUTHOR]

The aim of this paper is to offer a critical view on the role of emotions in financial markets. More specifically, I pretend to analyze the relationship between emotions and the socio-structural conditions of these markets. I propose an approach based on a) secondary ethnographic sources through which it is possible to explore the individual inter-subjectivity of the financial actors and b) a specific kind of financial literature whose main goal is to propose a behavioral-emotional regulation model for traders. According to several main concepts from Norbert Elias' sociology, I suggest an analytical scheme which connects the macro-sociological and micro-sociological aspects related to the presence and regulation of financial emotions. In this sense, I try to respond to two key questions: a) what are the typical emotions experienced by financial actors and which are their functions in the investment decision process? and b) which emotional regulation patterns are proposed to these actors in order to complete successful financial operations? [ABSTRACT FROM AUTHOR]

The aim of this paper is to offer a general perspective on the "victor/vanquished" dichotomy as a result of the new power balance in the period following the Spanish Civil War. The power balance administered by the Franco regime includes, inevitably, the "vanquished" management. I argue that the "victor/vanquished" distinction provides a sociological background to speak about the "two Spains" meta-historical metaphor as a social reality during Francoism. [ABSTRACT FROM AUTHOR]

The aim of this paper is to analyse self-help books using an analytical approach based on the civilization process theory of Norbert Elias, which explains the code for management of conduct and the emotions, here referred to as the «reflective civilization code». The study of the code involves a presentation of its contents as well as a statement of the arguments used to support advice and precepts regarding the regulation of conduct and the emotions. Finally, we propose a characterization of the social bases of the code taking the theoretical contributions of the so-called «Anglo-Foucaultian» theories as a model. [ABSTRACT FROM AUTHOR]

Nowadays, after suffering a fracture in an upper or lower limb, a plaster cast is placed on the affected limb. It is a very old and efficient technique for recovery from an injury that has not had significant changes since its origin. This project aims to develop a new low-cost smart 3D printed splint concept by using new sensing techniques. Two rapidly evolving Advanced Manufacturing (AM) technologies will be used: 3D scanning and 3D printing, thus combining engineering, medicine and materials evolution. The splint will include new small and lightweight sensors to detect any problem during the treatment process. Previous studies have already incorporated this kind of sensor for medical purposes. However, in this study it is implemented with a new concept: the possibility of applying treatments during the immobilization process and obtaining information from the sensors to modify the treatment. Due to this, rehabilitation treatments like infrared, ultrasounds or electroshock may be applied during the treatment, and the sensors (as it is showed in the study) will be able to detect changes during the rehabilitation process. Data of the pressure, temperature, humidity and colour of the skin will be collected in real time and sent to a mobile device so that they can be consulted remotely by a specialist. Moreover, it would be possible to include these data into the Internet of Things movement. This way, all the collected data might be compared and studied in order to find the best treatment for each kind of injury. It will be necessary to use a biocompatible material, submersible and suitable for contact with skin. These materials make it necessary to control the conditions in which the splint is produced, to assure that the properties are maintained. This development, makes it possible to design a new methodology that will help to provide faster and easier treatment. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this paper is to characterize a new structural bi-material (scaffold and filler). Design/methodology/approach: The bi-material has been obtained by means of an additive manufacturing system consisting of a fused filament fabrication extruder head and an epoxy resin depositor head. The new bi-material will consist of a thermoplastic material that will serve as the main structure and an epoxy resin that will serve as a filler and adhesion between layers. The creation of this new bi-material will improve the physical–chemical and mechanical properties with respect to the thermoplastic material. This paper will focus on the impact behavior of IZOD and the impact behavior of punctures. Findings: The new polylactic acid (PLA) and epoxy bi-material allow improvements in toughness and puncture impact resistance compared to the PLA thermoplastic. This increase in toughness is between 20% and 30% depending on the orientation of the print. In the same way, the energy absorbed in the puncture impact test has been increased by 42%–48%. Practical implications: The improvement in the impact absorption capacity of this new bi-material makes it ideal for the manufacture of medical parts in which customization, lightness and impact resistance are their main characteristics such as sports protection systems. Originality/value: The originality of creating parts through additive manufacturing that combines a material generated with cold extrusion, such as epoxy resin and a material generated with hot extrusion, such as thermoplastics, lies in the unique synergy that this mixed and simultaneous technique offers. By uniting these two manufacturing methods, it allows the exploration of new physical and chemical properties in the resulting parts, taking advantage of the individual advantages of each material. This combination opens the door to the creation of components with a wider range of characteristics, from strength and durability to flexibility and temperature resistance, thus offering innovative and versatile solutions for various applications in fields such as engineering, medicine and design. [ABSTRACT FROM AUTHOR]

For certain musculoskeletal complex rupture injuries, the only treatment available is the use of immobilization splints. This type of treatment usually causes discomfort and certain setbacks in patients. In addition, other complications are usually generated at the vascular, muscular, or articular level. Currently, there is a really possible alternative that would solve these problems and even allows a faster and better recovery. This is possible thanks to the application of engineering on additive manufacturing techniques and the use of biocompatible materials available in the market. This study proposes the use of these materials and techniques, including sensor integration inside the splints. The main parameters considered to be studied are pressure, humidity, and temperature. These aspects are combined and analyzed to determine any kind of unexpected evolution of the treatment. This way, it will be possible to monitor some signals that would be studied to detect problems that are associated to the very initial stage of the treatment. The goal of this study is to generate a smart splint by using biomaterials and engineering techniques based on the advanced manufacturing and sensor system, for clinical purposes. The results show that the prototype of the smart splint allows to get data when it is placed over the arm of a patient. Two temperatures are read during the treatment: in contact with the skin and between skin and splint. The humidity variations due to sweat inside the splint are also read by a humidity sensor. A pressure sensor detects slight changes of pressure inside the splint. In addition, an infrared sensor has been included as a presence detector. [ABSTRACT FROM AUTHOR]

The article focuses on protest launched by Czechoslovak's President Alexander Dubcek against political power of Soviet Union. Various topics discussed include enforcement of socialism in the region, freedom of expression allowed by the government for Czechoslovak's population and Catholic tradition followed over there.

During an FDM production process, there are different external disturbances to the characteristics of the machine that can affect to the production process. These disturbances will cause the final result differs from the desired one. Moreover, these disturbances, such as temperature or chamber humidity, are extremely important in case of using biocompatible materials. The use of these kind of materials with not controlled environment, can cause them to modify or loss of their properties; what will make the product unusable. Apart from these external disturbances, the conditions of the machine to which the material is subjected must also be considered, such as temperature, vibrations or extrusion speed. The monitoring of all these data will allow to know the conditions to which the product was exposed during the process. In this way, it will be able to verify the validity of the final product. For these reasons, the purpose of this work is to monitor the conditions of production of structures with biocompatible materials by fused deposition modelling (FDM) technique. This monitoring will allow us to obtain a report that guarantee the technical and geometrical characteristics of the model and the biomaterial properties. The parameters chosen to be monitored are: Diameter of filament use, temperature in extrusion nozzle, ambient temperature in closed chamber, ambient humidity in closed chamber. The obtained results, after collected and analysing the data, present variations of up to 3% in the temperature of the nozzle of the extruder with respect to set temperature. In the case of the filament diameter the difference with respect to the value provided from the filament supplier is of 13,7%. In addition, the results show how the ambient humidity in closed chamber has changed by 2 percentage points and the ambient temperature in closed chamber has been increased 6,52 °C with respect to the set values. [ABSTRACT FROM AUTHOR]

The main purpose of this paper is to present a system to detect extrusion failures in fused deposition modelling (FDM) 3D printers by sensing that the filament is moving forward properly. After several years using these kind of machines, authors detected that there is not any system to detect the main problem in FDM machines. Authors thought in different sensors and used the weighted objectives method, one of the most common evaluation methods, for comparing design concepts based on an overall value per design concept. Taking into account the obtained scores of each specification, the best choice for this work is the optical encoder. Once the sensor is chosen, it is necessary to design de part where it will be installed without interfering with the normal function of the machine. To do it, photogrammetry scanning methodology was employed. The developed device perfectly detects the advance of the filament without affecting the normal operation of the machine. Also, it is achieved the primary objective of the system, avoiding loss of material, energy, and mechanical wear, keeping the premise of making a low-cost product that does not significantly increase the cost of the machine. This development has made it possible to use the printer with remains of coil filaments, which were not spent because they were not sufficient to complete an impression. Also, printing models in two colours with only one extruder has been enabled by this development. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this paper is to analyze the aerodynamic improvements obtained in a wing section with a NACA 0018 airfoil manufactured using the fused deposition modeling (FDM) technique with regard to a smooth surface made by milling. The creation of micro-riblets on the surface of the airfoil, due to the deposition of the material layer by layer, improves the general aerodynamic performance of the parts, provided that the riblets are parallel to the flow line. The incidence of the thickness of the thread deposited in each layer – to be the variable on which the geometry of the riblets is based – was studied. Design/methodology/approach: The wing section was designed using 3D software. Three different models were designed by rapid prototyping, using additive and subtractive manufacturing. Two of the profiles were manufactured using FDM varying the thickness of the layer to be able to compare the aerodynamic improvements. The third model was manufactured using a subtractive rapid prototyping machine generating a smooth surface profile. These three models were tested inside the wind tunnel to be able to quantify the aerodynamic efficiency according to the geometry and the riblets size. Findings: The manufacture of an aerodynamic profile using FDM provides, in addition to the lightness and the ability to design parts with complex geometries, an improvement in the aerodynamic efficiency of 10 per cent compared with profiles with a smooth surface. Practical implications: With the aerodynamic advantage gained through the use of FDM positions, the additive manufacturing serves as an excellent alternative for the manufacture of lightweight aerodynamic parts, with low structural loading and with low Reynolds number (∼5·105). This technological advantage would be applied to the UAV (unmanned aerial vehicle) industry. Originality/value: The study carried out in this article demonstrates that the use of FDM as a manufacture process of end-used parts that are subject to movement generates an additional advantage that had not been considered. The additive manufacturing allows us to directly manufacture riblets by creating the necessary surface so as to reduce the aerodynamic drag. [ABSTRACT FROM AUTHOR]

Introduction: This article summarizes the clinical practice guideline (CPG) for the management of stage 3b, 4, and 5 chronic kidney disease (CKD) in the Social Security of Peru (EsSalud). Objective: To provide evidence-based clinical recommendations for the management of stage 3b, 4, and 5 CKD in EsSalud. Methods: A guideline development group (GDG) was formed, including specialists and methodologists. The GDG formulated 9 clinical questions. Systematic searches for systematic reviews and primary studies were conducted in PubMed from December 2020 to August 2021. Evidence was selected to answer the clinical questions posed. The certainty of the evidence was evaluated using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) methodology. The GDG used the GRADE methodology to review the evidence and formulate recommendations, points of good clinical practice (GPC), and management flowcharts. Finally, the CPG was approved with Resolution No. 88-IETSIESSALUD-2021. Results: This CPG addressed 9 clinical questions. Based on these questions, 17 recommendations (7 strong and 10 conditional), 28 GPC points, and 4 management flowcharts were formulated. Conclusion: This article summarizes the methodology and evidence-based conclusions of the CPG for the management of stage 3b, 4, and 5 CKD in EsSalud. [ABSTRACT FROM AUTHOR]

Most musculoskeletal injuries occur during the work routines in different areas, due to repetitive and sustained movements, they are often located in the shoulder. For workers in the building sector, the repetitive movements and displacements occur under load and unnatural postures of the shoulder joint. For this reason, this study aims to model in 3D the biological components which form the shoulder joint for the later finite element analysis. Three cases with different loads have been considered for this study. Due to a linear and isotropic joint approach it has been possible to evaluate the tensions in the main components of the shoulders: muscles, tendons and ligaments. The methodology used allowed obtaining an improved mesh of the shoulder joint to analyse real situations with finite element method analysis with applications in the field of sports medicine, work, etc. Furthermore, the simplification adopted for modelling the joint muscles, as 1D elements in the finite element model has made it possible to establish different positions of human joint without mesh again each of the studied positions. The results are consistent with the states of applied loads. In fact, the maximum stresses in bones are in the insertion areas of the ligaments. Due to the static positions of the joint under study, the muscles do not support high stresses. According to the stresses distribution, the maximum values are in the zones of tendons. From the result analysis, it is observed how the stresses distribution in the cartilage area maintains coherence with reality since the maximum stresses appear in the lower half of the cartilage. In this area in which the Humerus-scapula contact is greater, the compression tensions are greater. [ABSTRACT FROM AUTHOR]

The purpose for this study is to obtain a new composite manufacturing system based on Additive Manufacturing techniques that allows the creation of parts for the medical industry. These pieces will be resistant, lightweight and may have geometries more complex than those created with traditional systems of composite material. The new system is based on the union of two heads on a 3D Rep-Rap printer. One of the heads is an extruder head of thermoplastic Fused Filament Fabrication (FFF) and the other is a dosing head, based on the Robocasting technique, designed to be assembled on the 3D printer. Thermoplastics material and epoxy resin will be used. The alternate printing of both materials generates a piece of composite material. This new technique will allow to increase the structural properties of the piece in the XY plane. The new additive manufacturing system allows to obtain mechanical improvements both in the modulus of elasticity and in the tensile strength. Increase the modulus of elasticity of a value between 50 and 80% depending on the thermoplastic filament used. In the same way the tensile strength has increased between 50 and 60%. The improvement in the strength / weight ratio allows to this new additive manufacturing system to create medical pieces in which the lightness and resistance are its main characteristic, such as orthopedic prostheses.The results show that the use of FFF together with Robocasting, as a manufacturing process for end-use parts, generates an additional advantage that had not been considered until now. The combination of a thermoplastic and an epoxy resin opens a new path in the additive manufacturing since it allows creating pieces with new qualities without being conditioned by the design. [ABSTRACT FROM AUTHOR]

Motion tracking techniques have been extensively studied in recent years. However, capturing movements of the upper limbs is a challenging task. This document presents the estimation of arm orientation and elbow and wrist position using wearable flexible sensors (WFSs). A study was developed to obtain the highest range of motion (ROM) of the shoulder with as few sensors as possible, and a method for estimating arm length and a calibration procedure was proposed. Performance was verified by comparing measurement of the shoulder joint angles obtained from commercial two-axis soft angular displacement sensors (sADS) from Bend Labs and from the ground truth system (GTS) OptiTrack. The global root-mean-square error (RMSE) for the shoulder angle is 2.93 degrees and 37.5 mm for the position estimation of the wrist in cyclical movements; this measure of RMSE was improved to 13.6 mm by implementing a gesture classifier. [ABSTRACT FROM AUTHOR]

The application of tribology in dentistry is growing rapidly, intense research has been conducted to develop an understanding of dental tribology for better selection of artificial materials and dental implant design. Dental biotribology, has been one of the most important branches in biotribology in recent years. The aim of this research is to investigate the tribological performances in the tooth-to-tooth contact and material-to-natural tooth contact (zirconia vs. zirconia and natural tooth vs. zirconia). The presented research was carried out by testing the above mentioned tribological pairs with the use of a reciprocating tribometer under lubricated conditions (artificial saliva). The normal force used in the tests was 20 N the time for each test was of 60 min. The stroke length was 2 mm, according to the range of displacement used in scientific literature. The wear mass loss evaluation was evaluated by using a gravimetric method. In order to characterize the wear mechanisms, present in the worn surfaces after each of tribo-tests, a topographic analysis was carried with a 3D non-contact optical profiler. The results show that the minimum value of the COF is obtained in the case of Zirconia vs. Zirconia tribo-couple. The results on the wear mass loss show a very low wear rate when coupling in tribological condition natural tooth with a ceramic restoration (a mean value of 0.5 mg was found). This rate is even lower when the contact is between two artificial zirconia teeth. [ABSTRACT FROM AUTHOR]