Substitutive Press-Bolster and Press-Ram Models for the Virtual Estimation of Stamping-Tool Cambering

Today’s stamping simulations are realized by ignoring the elastic deformation of the press and tooling system through the assumption of a rigid behavior and a perfect press stroke. However, in reality, the press and tool components deform elastically and are one of the major error sources for the final adjustment and blue-spotting of the dies. In order to tackle this issue, a new approach is proposed in this study that substitutes the press stiffness by means of a substitutive model composed of cost-effective shell and beam elements. The substitute model was calibrated using full-scale measurements, in which a 20,000 kN trial press was experimentally characterized by measuring its deformation under static loads. To examine the robustness of the substitute model, a medium-size tool and a large-size tool were simulated together with the substitutive model. To this end, a B-pillar tool was re-machined based on the substitute-model results and a new cambering procedure was proposed and validated throughout the blue-painting procedure. The newly developed substitute model was able to replicate the global stiffness of the press with a high accuracy and affordable calculation time. The implementation of the findings can aid toolmakers in eliminating most of the reworking and home-line trials.     

Analysis of the Part Distortions for Inconel 718 SLM: A Case Study on the NIST Test Artifact

The present paper evaluates the misalignment and geometry distortion of the standard National Institute of Standards and Technology (NIST) test artifact in Inconel 718 alloy, when several layers with and without supports are employed to manufacture it by the Selective Laser Melting (SLM) process. To this end, a coordinate-measuring machine (CMM) is used to measure the geometrical distortion in each manufacturing configuration, following the same measurement protocol. The results show that the laser path strategy favors a thermal gradient which, consequently, induces geometrical distortions in the part. To prove this hypothesis, a numerical simulation is performed to determine the thermal gradient and the pattern of the residual stresses. It was found that the geometrical distortion certainly depends on the position of the feature position and laser strategy, where thermal cycles and residual thermal stresses had an impact in the end-part geometry, especially if a high strength-to-weight ratio commonly used in aeronautics is present.     

Effects of Protein Versus Carbohydrate Supplementation on Markers of Immune Response in Master Triathletes: A Randomized Controlled Trial

Objective: This study examines the long-term effects of ingesting hydrolyzed beef protein versus carbohydrate on indirect markers of immunity during 10 weeks of endurance training in master-aged triathletes (n?=?16, age 35–60?years).

Methods: Participants were randomly assigned to either a hydrolyzed beef protein (PRO, n?=?8) or nonprotein isoenergetic carbohydrate (CHO, n?=?8) condition, which consisted of ingesting 20?g of each supplement, mixed with water, once a day immediately post workout, or before breakfast on nontraining days. Salivary human neutrophil peptides (HNP1–3) were measured before and after performing an incremental endurance test to volitional exhaustion at both pre and post intervention. Additionally, baseline levels of platelets, neutrophils, eosinophil basophils, monocytes, and lymphocytes were determined at pre and post intervention.

Results: No significant changes in baseline concentration and secretion rate of salivary HNP1–3 were observed for either treatment. The CHO group showed a nonsignificant decrease in resting HNP1–3 concentrations following the intervention (p?=?0.052, effect size d?=?0.53). Protein supplementation demonstrated a significant reduction in lymphocyte counts pre to post intervention (mean [SD]: 2.30 [0.57] vs. 1.93 [0.45] 10³/mm³, p?=?0.046, d?=?0.77), along with a moderate but not statistically significant increase (d?=?0.75, p?=?0.051) of the neutrophil-to-lymphocyte ratio.

Conclusions: In master-aged triathletes, postworkout ingestion of only protein, with no carbohydrate, may not be as effective as carbohydrate alone to attenuate negative long-term changes of some salivary and cellular immunological markers. Future studies should consider the co-ingestion of both macronutrients.     

Obligate anaerobes are abundant in human necrotizing soft tissue infection samples – a metagenomics analysis

Necrotizing soft tissue infections (NSTIs) are associated with high morbidity and mortality and are increasing in incidence. Proper identification of the microbial causes of NSTIs is a crucial step in diagnosis and treatment, but the majority of data collected are culture based, which is biased against fastidious organisms, including obligate anaerobes. The goal of this study was to address this gap in knowledge by characterizing NSTI microbial communities through molecular diagnostics. We performed 16S rRNA sequencing on human NSTI samples and identified five genera most commonly found in NSTIs (Prevotella, Bacteroides, Peptoniphilus, Porphyromonas, and Enterococcus). We found that a >70% contribution of obligate anaerobes to the bacterial population distribution was associated with NSTI mortality, and that NSTI samples, from both survivors and non‐survivors, had an increased relative abundance of gram negative bacteria compared to those of abscess patients. Based on our data, we conclude that obligate anaerobes are abundant in NSTIs and a high relative abundance of anaerobes is associated with a worse outcome. We recommend increasing anaerobe antibiotic coverage during the treatment of NSTIs even when anaerobes are not found by traditional clinical microbiology methods, and especially when there is a clinical suspicion for anaerobe involvement.     

Understanding eating behaviours in Spanish women enrolled in a weight-loss treatment

Aim. To identify the beliefs and attitudes of a sample of obese and overweight Spanish women undertaking a weight‐loss treatment. Background. Obesity is a global epidemic. Weight‐loss treatments focus on changing eating behaviours; however, many patients fail to adhere to the diet. This suggests that more effective behaviour‐change interventions are required to help people change their eating behaviours. According to the theory of planned behaviour (TPB) human behaviour is influenced by beliefs. Identification of people's beliefs is an essential step in the design of behaviour‐change interventions. Design. A qualitative approach was employed using semi‐structured interviews to interview participants. Seventeen obese and overweight Spanish women enrolled in a weight‐loss treatment were recruited using a criterion sample strategy. Findings. Participants’ reported beliefs referring to the benefits of losing weight and the emotions related to dieting. The more positive these beliefs were the more positive their attitude towards the diet seemed to be. Findings highlight the importance of follow‐ups in creating a subjective norm to maintain a diet. Perceived behavioural control to diet seemed to be related to beliefs about social support; whereas beliefs about lack of willpower to overcome temptations seemed to decrease perceived control over eating behaviours. Conclusions. Participants reported several beliefs and attitudes that offer plausible explanations of their eating behaviours. Data from this study seemed to fit the propositions of the TPB and could be used in further research to develop effective eating behaviour‐change interventions. Relevance to clinical practice. Nurses could use the TPB to assess individuals’ attitudes, beliefs and expectations when following a diet. That assessment would provide insight into what aspects are relevant for individual patients when dieting, which could lead to more effective diet behaviour‐change interventions being designed.     

Microneedles: A New Frontier in Nanomedicine Delivery

This review aims to concisely chart the development of two individual research fields, namely nanomedicines, with specific emphasis on nanoparticles (NP) and microparticles (MP), and microneedle (MN) technologies, which have, in the recent past, been exploited in combinatorial approaches for the efficient delivery of a variety of medicinal agents across the skin. This is an emerging and exciting area of pharmaceutical sciences research within the remit of transdermal drug delivery and as such will undoubtedly continue to grow with the emergence of new formulation and fabrication methodologies for particles and MN. Firstly, the fundamental aspects of skin architecture and structure are outlined, with particular reference to their influence on NP and MP penetration. Following on from this, a variety of different particles are described, as are the diverse range of MN modalities currently under development. The review concludes by highlighting some of the novel delivery systems which have been described in the literature exploiting these two approaches and directs the reader towards emerging uses for nanomedicines in combination with MN.