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PURPOSE The aim of this study was (1) to assess AT through 13 different mathematical approaches and to compare their results; and (2) to understand if AT occurs after moderate WL. METHODS Ninety-four participants [mean (SD); BMI, 31.1 (4.3) kg/m2; age, 43.0 (9.4) years; 34% females] underwent a 1-year lifestyle intervention (clinicaltrials.gov ID: NCT03031951) and were randomized to intervention (IG, n = 49) or control groups (CG, n = 45), and all measurements were made at baseline and after 4 months. Fat mass (FM) and fat-free mass (FFM) were measured by dual-energy X-ray absorptiometry and REE by indirect calorimetry. AT was assessed through 13 different approaches, varying in how REE was predicted and/or how AT was assessed. RESULTS IG underwent a mean negative energy balance (EB) of 270 (289) kcal/day, p

This paper is focused on solving the problems of positioning and alignment of rivets in double-sided self-pierce riveting by means of flat-bottom holes that are previously machined in the overlapped sheets with greater mechanical strength. The work combines experimentation in joints made from dissimilar materials (aluminium AA5754-H111 and polyvinylchloride) with finite element modelling to investigate the influence of the flat-bottom hole geometry in the overall joining mechanisms. It is shown that the use of flat hole-bottom holes with rivets having identical chamfered angles in both ends is unable to create undercuts and to produce form-closed mechanical interlockings. Undercuts are created if different chamfered angles in the rivet ends are introduced to compensate the greater or lesser difficulty of the rivets to pierce through sheets with different mechanical strengths. Destructive shear and peel tests performed with different types of joints confirm the good performance of the joints produced by double-sided self-pierce riveting with flat-bottom holes.

This paper is focused on fastened hybrid busbars made from copper and aluminium with the purpose of analysing the influence of the steel bolts, of their tightening torque and of the surface condition of the sheets on the electric current flow and electric resistance of the joints. The methodology combines experimentation with unit cells that are representative of the joints and electro-mechanical numerical simulation using a finite element computer program developed by the authors. Results are a step forward in understanding the combined influence of bolts, contact pressure and surface roughness on the electric performance of fastened hybrid busbars. Design guidelines for dimensioning the cross sections of the copper and aluminium sheets and for effectively distributing bolts across the contacting surfaces are also provided.

This paper presents a new resistance element welding process capable of producing invisible lap joints between steel-polymer-steel composite laminates. The process involves pre-drilling a flat-bottom hole in each laminate to remove the polymer core and one of the steel sheets, and positioning a cylindrical insert inside the two adjoining holes for subsequent resistance welding. Finite element modeling is utilized to construct the weldability lobe and to identify the parameters that lead to the formation of acceptable joints. Experimental results confirm the applicability of the process to produce invisible lap joints without signs of material protrusions or local indentations resulting from squeezing the polymer out to create contact between the steel sheets. Destructive peel and shear tests allow determining the maximum forces that the joints can safely withstand and comparing their performance against alternative joined by forming lap joints in which the mechanical interlocking is also hidden inside the laminates.

This paper is focused on the formability of wire-arc additively manufactured AISI 316L stainless steel sheets with the purpose of analysing the feasibility of including this material in hybrid additive manufacturing chains involving sheet metal forming operations. Conventional tensile tests performed in specimens obtained from different orientations to the building direction were carried out to characterise the mechanical properties, the strain loading paths and the limiting strains at fracture. Microstructure observations combined with fractography analysis add insight to the results by establishing a link between the forming limits by fracture and the crack opening mechanisms. Results obtained for wrought commercial AISI 316L stainless steel sheets are included for comparison purposes and reveal that the additively manufactured sheets have a much stronger anisotropic behaviour and poorer formability due to their dendritic-based microstructure. Still, the forming limits obtained from the experiments allow concluding that the additively manufactured sheets can withstand large plastic deformations and, therefore, can be used in hybrid additive manufacturing routes.

This paper is focussed on the mechanical and formability characterisation of wire-arc additive manufactured (WAAM) AISI 316-L stainless-steel tubes. The methodology to be presented involved carrying out tension and ring hoop tension tests on specimens extracted from the tube longitudinal, transverse and inclined directions. The force evolutions, acquired from the load cells, and the strain measurements, retrieved from digital image correlation and from thickness measurements along the cracks, allowed obtaining the stress-strain curves, the strain paths and the onset of failure by fracture for the three different tube directions. Special attention was paid to the ring hoop test, which was revisited to determine the appropriateness of using ring specimens with one or two dumbbell geometries. The originality of using the ring hoop tension test in WAAM tubes with strong anisotropic behaviour allowed obtaining strain loading paths that range from plane strain to pure shear deformation conditions. Resort to commercial AISI 316-L stainless-steel tubes during the presentation is included for reference purposes.

Integration of tube end forming operations in metal additive manufacturing routes has a great potential for the fabrication of customized features in additively deposited hollow parts. This paper is focused on the integration of tube expansion with rigid tapered conical mandrels to highlight the advantages in the construction of overhanging flares derived from the elimination of support structures and prevention of humping. The work draws from the mechanical and formability characterization of stainless steel AISI 316L tubes produced by wire arc additive manufacturing (WAAM) to the experimental and numerical simulation of the construction of overhanging flares by tube expansion. Strain loading paths obtained from digital image correlation and finite element analysis combined with the strain values at the onset of necking and fracture allow determining the critical ductile damage that additively deposited tubes can safely withstand. Results show that despite formability of additively deposited tubes being influenced by a dendritic based microstructure, their performance is adequate for tube end forming operations, such as tube expansion, to be successfully integrated in metal additive manufacturing without the need of using expensive hardware and complex deposition strategies.

This paper is focused on double-sided self-pierce riveting (DSSPR) of overlapped sheets made from dissimilar materials with very different mechanical strengths. The methodology draws from previous work on sheets made from similar or identical materials and the extension to dissimilar materials is built-upon a combined experimental and numerical investigation that makes use of AA5754-H111 aluminum and polyvinylchloride sheets. Results show that reengineering of conventional DSSPR by modification of the chamfered rivet angles to account for the different resistances to penetration of the two materials is not effective, because it cannot solve the formation of asymmetric mechanical interlockings with very small undercuts in the harder sheet material. The proposal of an innovative two-stroke DSSPR process in which the tubular rivet is first forced through the harder sheet with the help of a dedicated compression tool, and only subsequently pressed through the softer sheet, proves to be effective in obtaining symmetric joints with good undercuts in both sheets. Destructive shear tests confirm the good performance of the joints produced by means of the new proposed two-stroke DSSPR.

This paper is focused on innovative self-pierce riveting concepts to produce invisible joints in sheet-sheet and tube-sheet connections. The common element to these two different types of joints is the use of tubular rivets with chamfered ends, which are accessories in the case of sheet-sheet joints and constitutive (structural) elements in the case of tube-sheet joints. The presentation draws from the deformation mechanics of double-sided self-pierce riveting for producing lap joints in overlapped sheets to the development of self-pierce riveting of tubes to sheets, which is a new joining by forming process capable of attaching a sheet to the end of a tube, at room temperature. Aluminum sheets, carbon and stainless-steel tubes are utilized to demonstrate the effectiveness of the new self-pierce riveting concepts and finite element modelling using an in-house computer program gives support to the overall presentation. Destructive tests are carried out to evaluate the destructive strength that the joints are capable to withstand without failure.

Flexible roll forming process is an advanced manufacturing process, for producing complex and lightweight profiles with variable cross-section. One of the major observed defects in this process is the flange wrinkling of the profiles, which has limited its development especially for the automotive industry. In this paper, the deformation mechanics of the flexible roll forming process is revisited, and the methodology for predicting the onset of wrinkling, which had previously been developed based on the wrinkling limit curve in the space of effective strain versus stress triaxiality, is improved. Then, a new criterion based on the wrinkling limit curve is proposed to predict the possibility of wrinkling in finite element analysis. The criterion is applied to analyze the influence of geometric parameters of the variable cross-section profile and material properties of the sheet on the occurrence of wrinkling. The prediction accuracy is evaluated by performing experiments with different profile shapes. Results show that the new proposed criterion can successfully predict the onset of wrinkling in the flexible roll forming process, and its utilization is recommended for predicting wrinkling in the finite element analysis of sheet metal forming processes.

This paper presents a new joining by forming process capable of attaching a sheet to the end of a tube without the need of accessories and extra materials. The process is named as ‘self-pierce riveting of tubes to sheets’ and is an extension to sheet-tube connections of the working principle of double-sided self-pierce riveting utilized for connecting two overlapped sheets. The process requires tubes with chamfered ends to be pushed against the sheets and its ends to flare (curl) in order to create an interlocking that holds the sheets and tubes tightly together. The resulting joints are invisible because the interlockings are hidden inside the sheets. The presentation draws from deformation mechanics and identification of the major parameters to characterization of the interlocking and evaluation of the pull-out destructive strength that the new joints are capable to withstand without failure. Aluminium sheets and carbon steel tubes are utilized to demonstrate the effectiveness of the new joining by forming process and to demonstrate its ability to connect sheets and tubes made from dissimilar materials at room temperature. Finite element modelling using an in-house computer program gives support to the presentation.

Following previous developments of the authors on deformation-assisted joining of metal tube-sheet connections by annular sheet squeezing, it is the aim and objective of this paper to extend the process applicability domain to polymers and composites. The presentation includes an overview of the main operative parameters, typical plastic deformation modes and process workability limits. Experiments and finite element simulations allowed comparing the results obtained with dissimilar materials against those earlier obtained with metal tubes and sheets. Results confirm the possibility of combining dissimilar materials in form-fit and force-fit tube-sheet connections for applications in flexible lightweight structures.

This paper presents a new joining by forming process named as “double-sided self-pierce riveting” that makes use of tubular rivets with simple geometry placed in-between two sheets to be joined. The sheets are pushed against each other by flat parallel punches so that the rivets are forced through the sheets and their ends are flared (curled) to create mechanical interlocking’s which holds the sheets tightly together. The methodology draws from deformation mechanics and identification of major process parameters, to fabrication and destructive testing of joints. Experimental work in AA5754-H111 aluminum sheets and AISI 304 stainless steel tubular rivets was supported by finite element modelling. Results allow concluding that the new process incorporates the advantages of conventional self-pierce riveting and successfully overcomes its main disadvantages, namely the material protrusions above and below the sheet surfaces and the difficulties in joining sheets of dissimilar materials with large thicknesses. The new mechanical joints also have the advantage over those produced by clinching and self-pierce riveting of being invisible, because they are hidden inside the cross section of the overlapped sheets.

This paper presents a new joining by forming process to produce lap joints in metal-polymer sandwich composite sheets. The process involves drilling a blind hole in each sheet for removing the upper metal skin and the polymer core layer, and fixing them together by compressing a metal insert placed in-between to obtain a form-fit mechanical nugget. The cross-section of the joint resembles that of resistance spot welding, with the cold formed insert (‘nugget’) hidden inside the sheets. The geometry and size of the inserts are analysed by finite elements and experimentation to determine the effectiveness and performance of the new joints.

© Author(s) (or their employer(s)) 2022. No commercial re-use. See rights and permissions. Published by BMJ., Objectives: Many athletes struggle in managing the end of their career, often gaining weight and adopting unhealthy lifestyles. Lifestyle programmes targeting former athletes who have gained substantial fat mass (FM) postsports career are lacking. We studied the effects of the Champ4Life programme on body composition and other health-related outcomes in former elite athletes with overweight or obesity. Methods: Ninety-four former athletes(42.4±7.3 y, 34.0% female) were recruited and randomly assigned to either an intervention group (IG; n=49) or a control group (CG; n=45). The IG attended 12 educational sessions addressing physical activity, weight management and nutrition. They also had a nutrition appointment aimed to prescribe a moderate caloric deficit(~300-500 kcal/day). Dual-energy X-ray absorptiometry was used to assess body composition. The Short-Form Health Survey-36 questionnaire was used to measure general health-related quality of life. Blood samples were collected to assess cardiometabolic health parameters. Results: At 12 months, the IG lost more weight (estimated difference (ED)=-5.3 kg; -6.9 to -3.8), total FM (ED=-4.1 kg; -5.4 to -2.8) and abdominal FM (ED=-0.49 kg; -0.64 to -0.33) than did the CG (p's, Financial support was provided by the Portuguese Institute of Sports and Youth and by the International Olympic Committee, under the Olympic Solidarity Promotion of the Olympic Values Unit (Sports Medicine and Protection of Clean Athletes Programme). The current work was also supported by national funding from the Portuguese Foundation for Science and Technology within the R&D units UIDB/00447/2020. CLN and RF were supported with a PhD scholarship from the Portuguese Foundation for Science and Technology (SFRH/BD/143725/2019 and 2020.05397.BD, respectively)

Este artigo discute a questão do rigor em jornalismo, considerado nas suas dimensões técnica e ética, na perspetiva de o reabilitar enquanto eixo central da prática profissional. Para o efeito, introduz um conjunto de questões, a partir da conceptualização daquele princípio em instrumentos deontológicos. A saber: a verdade jornalística e os instrumentos necessários para a alcançar; o cruzamento de fontes, exercício que não deve esgotar-se no chamado contraditório; a liberdade de expressão e os discursos de ódio; os diversos tipos de fake news; os efeitos perniciosos do clickbait e um fenómeno que o autor designa de fast food noticioso, prejudicial ao efetivo cumprimento da missão do jornalismo em sociedades democráticas.

This paper investigates the applicability of single point incremental forming to fabricate stiffening grooves in thin metallic panels. The work combines experimentation, finite element and analytical modelling to determine the required forces and the maximum allowable groove depths that can be produced without tearing. The analytical modelling is based on a framework that was previously developed by the authors and combines in-plane membrane stretching and fracture forming limits. Comparison of the results obtained by the analytical framework against experimental and finite element data proves its effectiveness to replicate the deformation mechanics of groove stiffening by single point incremental forming. Results also prove that groove stiffening by single point incremental forming is an easy and effective alternative to conventional reinforcement of thin metallic panels by welding or fastening of stringers.

This paper is focused on extending the applicability domain of double-sided self-pierce riveting to the production of invisible lap joints in polymer sheets. The presentation draws from the working principle and identification of the main process parameters to aspects of design and fabrication of the tubular rivets and lap joints. The experimental work is carried out in polyvinylchloride sheets and stainless-steel tubular rivets and is supported by finite element modelling. It is shown that double-sided self-pierce riveting with adequate geometry of the tubular rivets can be used effectively to produce invisible lap joints in polymer sheets at room temperature with neither surface preparation and pre-drilling of holes nor material protrusions above and below the sheets after joining.

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This paper is focused on the integration of metal forming operations in hybrid systems that combine additive manufacturing (AM) by gas metal wire arc and subtractive manufacturing by machining. The investigation is carried out in AISI 316L stainless steel wire and draws from tensile testing to incremental sheet forming of truncated conical shapes. Commercial sheets from the same material are utilized for comparison purposes. Thickness measurements, digital image correlation (DIC), circle grid analysis (CGA) and microstructural and scanning electron microscopy (SEM) observations are carried out to understand how different is the mechanical behaviour of the deposited metal from that of commercial metal sheets and how significant is the influence of the deposited metal microstructure on its overall formability. Results confirm that integration of metal forming operations in hybrid AM routes is feasible despite the formability of deposited metal being smaller than that of the commercial metal sheets due to the strong anisotropy induced by the dendritic based microstructure of the deposited metal. Incremental forming of two deposited parts also allows concluding that integration of metal forming operations in hybrid AM systems is a step towards green and sustainable manufacturing by extending their field of applicability to the fabrication of complex ready-to-use parts requiring combination of different processes.

This paper is focused on injection by upsetting of sheet-formed side walls. The presentation draws from fundamental aspects of material flow to typical failures caused by buckling and by the development of material flaws. Results show that the utilization of two-piece blank holders in conjunction with an adequate selection of the die cavity thickness and the creation of relief-holes to allow divided material flow are effective and easy-to-implement strategies to increase process formability and ensure the production of sound sheet-bulk parts. The work is carried out in two completely different materials (polyvinylchloride and aluminium AA1050) and its originality stands not only for the investigation on sheet injection but also for the utilization of thermoplastics in sheet-bulk forming. Numerical modelling with finite elements gives support to the overall results and discussion.

Introduction. The heightened physical exertion stemming from greater physical loads in football matches has elicited greater development of physical conditioning in both players and referees. Material and methods. The current study consisted of a meta-analysis geared towards identifying the scientific data currently available on the training of referees. Results. With respect to the characterization of the training of football referees, the results of this study showed that there is a diversity of both its methods and contents. As a result of this and based on the support offered by the meta-analysis, a proposal for categorizing the contents of this training is presented. Testing-wise, the results also showed that the FIFA test fails to identify the varying intensities that occur within a match setting and to characterize the distribution of referees’ varying exertions throughout match settings. Lastly, the results of this study also indicated that the training of referees ought to include periodization guidelines over the course of a season, since doing so allows for the optimization and monitoring of referees’ performance.

This paper is focused on fixing sheets to tubes away from the tube ends by annular sheet squeezing. The main objectives are the investigation of the physics behind material separation at the cross-section recess corner of the punches and the determination of the appropriate squeezing depth values. The methodology combines experimentation and finite element modelling and the overall presentation is illustrated with selected test cases retrieved from the experimental work plan. Results show that material separation is caused by through-thickness shear, that forces and energy required to form the new surfaces are negligible and that appropriate squeezing depth values result from a compromise between the quality of the mechanical interlocking and the pull-out destructive strength of the joints.

This paper proposes a new joining by forming process to secure a sheet to a tube away from the tube end. The process is an alternative to welding, adhesive bonding, mechanical fastening or riveting and consists of squeezing the sheet adjacent to the outer tube radius, instead of applying direct loading on the tube itself as is customary in existing joining by forming processes. This process is cost effective, can be easily used on site and prevents cracking of the plastically deformed beads in tubular materials with low fracture toughness. The presentation combines experimentation and finite element modelling to identity the major process parameters, understand their influence in plastic flow and characterize the different modes of deformation that lead to acceptable and unacceptable joints. Utilization of a deformation-zone geometry parameter Δ , defined as the ratio of the sheet thickness to the cross-section recess length of the punch, is successfully utilized to characterize plastic flow inside the sheet thickness and to establish fundamental design rules. Appropriate values of the deformation-zone parameter in the range Δ = 2 − 3 and placed in-between the limiting values corresponding to inhomogeneous and homogeneous deformation, revealed adequate to obtain sound sheet-tube connections. The maximum pull-out forces are sensitive to the direction of applied loading due to the non-symmetric shape of the joints but no detachments were observed for forces up to 2 kN.

Este trabalho foi financiado pelo Concurso Anual para Projetos de Investigação, Desenvolvimento, Inovação e Criação Artística (IDI&CA) 2016 do Instituto Politécnico de Lisboa. Código de referência IPL/2016/CompSBJ_ISEL Submitted by Isabel Melo (imelo@sa.isel.pt) on 2019-07-29T09:59:38Z No. of bitstreams: 1 Experimental_MARLoja.pdf: 2048657 bytes, checksum: 5c5af5020ac2fe21c79ab3e66ecd0eb8 (MD5) Made available in DSpace on 2019-07-29T09:59:38Z (GMT). No. of bitstreams: 1 Experimental_MARLoja.pdf: 2048657 bytes, checksum: 5c5af5020ac2fe21c79ab3e66ecd0eb8 (MD5) Previous issue date: 2019-07 info:eu-repo/semantics/publishedVersion

This paper proposes a methodology to determine the formability limits of thin-walled tubes and to plot them in principal strain space and in the space of effective strain vs. stress-triaxiality. Digital image correlation (DIC), combined either with time-dependent methodologies or strain-force approaches, is utilized to identify the onset of failure by necking and obtain the corresponding limit strains. Thickness measurements and determination of the gauge length strains across the cracked regions are utilized to characterize the onset of fracture and to evaluate the fracture limit strains. Results show that the utilization of tube expansion with rigid punches and elastomers allow obtaining strain loading paths and fracture loci by necking and fracture across a wide range of tube forming conditions ranging from biaxial stretching in the first quadrant to pure tension in the second quadrant of principal strain space. The fracture forming line (FFL) is the first time ever determined for thin-walled tubes. The forming limit curve (FLC) and the FFL resemble those of sheet and strip materials and their use is of paramount importance in the design and optimization of tube forming processes.

Sheet-bulk forming (SBF) processes based on a combination of deep drawing and upsetting are being increasingly used to produce new sheet metal parts with significant changes in wall thickness to accommodate three-dimensional functional features such as solid bosses, teeth and ribs. The utilisation of sheet-bulk forming processes introduces additional complexity in the design, setup and costs of tooling due to the inherent high forces and complex material flow that easily lead to underfilling and failure in critical die regions. This paper is concerned with these issues and is focused on the development of a sheet-bulk forming demonstrator capable of replicating material flow and failure in sheet thickening, local sheet thickening and sheet injection operating conditions. The demonstrator combines sheet bending and upsetting operations with a flexible design concept based on the utilisation of active modular tool parts to allow different materials, geometries and tool concepts to be tested under laboratory conditions and rapidly transferred to industrial SBF tools.

This article presents a new type of bi-material coin with a polymer centre and a metal ring. The polymer-metal coin is fabricated by combination of coin minting and joining by forming in a single die stroke. The design of the coin is based on an analytical model built upon plasticity theory and plastic instability of circular plates under uniform radial edge compression. The analytical model and the bi-material coin concept are supported and validated by means of finite element modelling and experimentation. Destructive tests for pushing the polymer centre out of the metal ring demonstrate the effectiveness of the mechanical joint resulting from the interface contact pressure between the polymer and the metal. The new bi-material coin was developed to obtain new aesthetic effects for the collection market, and its polymer core can additionally be used for other applications such as the incorporation of advanced security features in high-denomination coins.

This article describes a methodology to characterize the failure limits by necking and fracture, and to determine the critical value of ductile damage in tube forming. The methodology makes use of digital image correlation, thickness measurements and force–displacement evolutions to obtain the strain loading paths and the strain values at the onsets of failure by necking and fracture. The onset of failure by necking is determined by a new technique that combines the strain and force–displacement evolutions whereas the fracture strains at the cracked regions of the tubes are obtained by a similar technique utilized by the authors in sheet metal forming. Transformation of the strain loading paths from principal strain space into the space of effective strain versus stress-triaxiality allows determining the critical experimental value of ductile damage at the onset of failure by necking. The methodology is applied to tube expansion with circular, elliptical and square cross-section punches and results confirm its importance and helpfulness for researchers and engineers involved in the development and optimization of industrial tube forming processes.

This paper proposes a new joining by plastic deformation process to connect sheets to rods that extends a previous idea of the authors to connect sheets to thin-walled tubes. The process makes use of boss forming for compressing the outer radius of the rods and pile-up material into annular flanges with controlled cross-section geometry and size. Special emphasis is put on the identification of the major operating parameters and on understanding their influence on material flow. Two different modes of deformation are identified and a distinction is made between unacceptable chip formation and successfully material pile-up to form the annular flanges that are needed to connect the sheets to the rods. Special design of the upper die to include a pressure ring is introduced as an efficient solution to prevent cracking of the new freshly formed surfaces of the rods during material pile-up. The presentation is supported by experimentation and finite element modelling and the overall performance of the new proposed joint is evaluated by means of a destructive pull-out test.

This paper presents a new joining method by a forming process for attaching sheets to tube ends. The process consists of two different forming stages carried out sequentially in a single stroke. Firstly, the free tube end is flared by compression with a contoured die, then is squeezed (indented) against the sheet surface to create a mechanical interlocking. The new process is carried out at an ambient temperature and, in contrast to existing joining by forming operations based on tube expansion, it avoids seal welds, tube protrusions above the sheet surfaces, and machining of grooves on the sheet holes to obtain the form-fit joints. The paper starts by analyzing the process deformation mechanics and its main operating variables and finishes by presenting examples that demonstrate its effectiveness for attaching sheets to tube ends made from polyvinylchloride and aluminum. Experimental and numerical simulation work provides support to the presentation.

This paper presents an injection lap riveting process to connect two sheets placed one on top of the other. The process is carried out at ambient temperature and differs from self-pierce riveting because its joining principle is based on plasticity and friction without fracture and formation of new surfaces. The working principle is based on two consecutive operations - first, a dovetail ring hole is machined in the lower sheet and then a semi tubular rivet is injected through the upper sheet into the dovetail ring hole of the lower sheet, by compression with a punch. The presentation is based on a combined experimental and numerical investigation and special emphasis is put on the influence of the dovetail ring hole geometry in material flow, riveting force, and pull-out and shear destructive forces. The last past of the paper includes details of a prototype cutting tool that was developed by the authors for producing the dovetail ring holes in-site and fostering the portability and applicability of the process.

The objective of this paper is to present a new hybrid additive manufacturing route for fabricating collector coins with complex, intricate contoured holes. The new manufacturing route combines metal deposition by additive manufacturing with metal cutting and forming, and its application is illustrated with an example consisting of a prototype coin made from stainless steel AISI 316L. Experimentation and finite element analysis of the coin minting operation with the in-house computer program i-form show that the blanks produced by additive manufacturing and metal cutting can withstand the high compressive pressures that are attained during the embossing and impressing of lettering and other reliefs on the coin surfaces. The presentation allows concluding that hybrid additive manufacturing opens the way to the production of innovative collector coins with geometric features that are radically different from those that are currently available in the market.

Characterisation of model asperity flattening under longitudinal subsurface elongation is presented with a variety of normal pressure, flank angle and strain hardening behaviour. A systematic investigation outlines an optimal specimen design to ensure a homogenous deformation field in the workpiece under stress-strain conditions, which are typical in sheet metal forming. Asperity flattening increases with normal pressure, and the longitudinal subsurface strain reduces the necessary yield pressure and promotes asperity flattening. When the flank angle is increased, the longitudinal stress component due to elongation gets smaller in the asperity, reducing the effect of longitudinal straining. Strain hardening decreases the asperity flattening rate as strain hardening extends the deformation field further into the underlying material, which results in less asperity flattening.

Trusted Platform Modules (TPMs) serve as the root of trust to design and implement secure systems. Conceived by the Trusted Computing Group, a computer industry consortium, components complying with the TPM 2.0 standard are stable and widely available. However, should large-scale quantum computing become a reality, the type of cryptographic primitives adopted in the current standard will no longer be secure. For this reason, this paper analyses the impact of adding three Post-Quantum (PQ) algorithms to a current non- Quantum Resistant TPM through software emulation. The experimental results give insight on the kind of implementation challenges hardware designers will face when integrating the new primitives onto the TPM, that typically features limited hardware resources and low power consumption. In particular, it is concluded that Kyber, NTTRU, and Dilithium can efficiently replace most of the functionality provided by Elliptic Curve Cryptography (ECC) and Rivest-Shamir-Adleman (RSA). In contrast, current PQ Direct Anonymous Attestation (DAA) protocols are currently not compact enough to fit into a hardware TPM.

Due to the Covid-19 crisis all around the world in 2020, the face-to-face meeting has been canceled. However, the paper selection process was completed. The accepted papers have been included in the ARITH-2020 proceedings and will soon be published on IEEE Xplore. They are also posted in the Programme section of this web site: http://arith2020.arithsymposium.org/; International audience; State-of-the-art implementations of homomorphic encryption exploit the Fan and Vercauteren (FV) scheme and the Residue Number System (RNS). While the RNS breaks down large integer arithmetic into smaller independent channels, its non-positional nature makes operations such as division and rounding hard to implement, and makes the representation of small values inefficient. In this work, we propose the application of the Hybrid Position-Residues Number System representation to the FV scheme. This is a positional representation of large radix where the digits are represented in RNS. It inherits the benefits from RNS and allows to accelerate the critical division and rounding operations while also making the representation of smaller values more compact. This directly benefits the decryp-tion and the homomorphic multiplication procedures, reducing their asymptotic complexity, in dimension n, from O(n 2 log n) to O(n log n) and from O(n 3 log n) to O(n 3), respectively and has resulted in noticeable speedups when experimentally compared to related art RNS implementations.

Patients with Strongyloides stercoralis infections are usually asymptomatic but massive hyperinfection may occur in patients with diseases associated with abnormal cell-mediated immunity or receiving immunosuppressive therapy. The authors present the clinical case of a 49-year-old man with a history of diarrhoea and cramping abdominal pain, generalized oedema, petechial rash, melanoderma, cough and dyspnoea. He presented hypokalaemia and arterial hypertension and was admitted with the diagnostic hypothesis of Cushing's syndrome or adrenocorticotropic hormone ectopic production. The patient developed respiratory failure associated with bilateral lung opacities and was admitted to the Intensive Care Unit. The abdominal computed tomography scan revealed liver and duodenal masses. The duodenal biopsy showed the presence of Strongyloides stercoralis and the liver biopsy showed the presence of small cell neuroendocrine carcinoma. The patient died 50 days after hospital admission. The high level of endogenous cortisol observed in this patient may have facilitated the progression to severe fatal infection. LEARNING POINTS Strongyloides stercoralis hyperinfection and disseminated disease can present as a multiorgan infection in immunocompromised patients with an appropriate clinical and epidemiological context.Strongyloides stercoralis hyperinfection and disseminated disease can present with no eosinophilia and negative parasitological stool tests in more than 70% of cases.