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Fernando J Martinez,1 Alberto Papi,2 Tobias Welte3,4 ,† Dave Singh,5 Dmitry V Galkin,6 Alessandro Guasconi,7 Stefania Pirondi,7 George Georges,7 Joseph Imperato,8 Ruben Hermans9 1Weill Cornell Medicine, New York–Presbyterian Hospital, New York, NY, USA; 2Research Center on Asthma and COPD, Department of Medical Sciences, University of Ferrara, Ferrara, Italy; 3Pneumonology and Infectiology, Member of the German Center of Lung Research, Hannover Medical School, Hannover, Germany; 4Biomedical Research in End Stage and Obstructive Lung Disease, German Center for Lung Research, Hannover Medical School, Hannover, Germany; 5Medicines Evaluations Unit, University of Manchester, Manchester University Foundation Hospitals Trust, Manchester, UK; 6Global Clinical Development, Chiesi USA, Cary, NC, USA; 7Global Clinical Development, Chiesi Farmaceutici, S.p.A, Parma, Italy; 8Medical Affairs, IQVIA Inc, New York, NY, USA; 9Medical Affairs, IQVIA Inc, London, UK†Prof. Tobias We 50% in 2020 compared with 2019. The proportions of patients with an exacerbation increased in most countries in 2021. Across each country, seasonal exacerbation increases seen during autumn and winter in pre-pandemic years were absent during the first year of the pandemic. The percentage of patients filling COPD prescriptions across each country increased by 4.53– 22.13% in 2019 to 9.94– 34.17% in 2021.Conclusion: Early, steep declines in exacerbation rates occurred in 2020 versus 2019 across all five countries and were accompanied by a loss of the seasonal pattern of exacerbation.Keywords: COPD exacerbation, chronic obstructive pulmonary disease, COVID-19, electronic health records, real-world study

Abstract Background The burnout phenomenon has been extensively investigated among health care professionals, particularly focusing on physicians and nurses. However, literature concerning burnout in clinical research is poor and often neglects the other professional categories involved. Methods In March 2019, all members of Italian Group of Clinical Research Coordinator were invited to participate to a web survey, consisting of three sections: general information and workload; Maslach Burnout Inventory (MBI) test; subjective perception of oneself’s work stress and possible causes. Results The majority of respondents felt a form of distress. The main source was contract type (31.2%), followed by workload (20.5%) and lack of skills recognition (17.8%). Results from MBI test confirmed the interviewees’ subjective perception: an intermediate level of emotional exhaustion (19.1 points) and a very high sense of reduced professional achievement (26.8 points) were observed. Both depersonalization and sense of reduced professional achievement showed weak to moderate correlations with emotional exhaustion. Emotional exhaustion was associated with contract type with high significance. Conclusion It is necessary to act on those qualitative factors that are greatly increasing the level of perceived stress, jeopardizing the quality of clinical research coordinators work and significantly amplifying the phenomenon of migration towards the private sector.

This work explores the influence of Additive Manufacturing (AM) parameters on the Mode I fracture toughness of polymer bonded joints. The motivation is that realizing AM parts to be later assembled can be convenient from the manufacturing standpoint and adhesive bonding avoids distortion and material modification due to heat while welding or the use of fasteners. PLA and ABS joints were tested and three different printing parameters (extruder temperature, printing speed and layer thickness) were selected to evaluate their influence on roughness, wettability and tensile behaviour of the adherends. A full-factorial Design of Experiment was chosen to study roughness and wettability because of the short sample manufacturing and measurement time, while a Taguchi L9 orthogonal array was selected for the tensile testsr to save manufacturing and testing time. The significance and the mutual interactions of printing parameters were identified by analysis of variance. Combinations yielding maximum and minimum values of the output, respectively, were used to produce adherends for Double Cantilever Beam (DCB) joints and evaluate the effect on Mode I fracture toughness, demonstrating that process parameters do have an effect on fracture toughness and that an optimum value can be found by simply operating on the AM setup. [ABSTRACT FROM AUTHOR]

The work illustrates how building parameters of the Additive Manufacturing process Fused Filament Fabrication can affect not only the mechanical properties but also the surface wettability and morphology. Wettability and morphology are relevant factors in bonded joints performance. Advantages of polymeric additive manufacturing are to allow a re-design of components with locally controlled properties and integrated functions. Major limitations are related to the lack of material testing standardization and constraints due to the build volume and to the object orientation for printability: the latter problem scan be addressed with the use of bonded joints that allow to create bigger assemblies from smaller parts optimally designed to take advantage of material orthotropy and without the structural drawbacks. In this study, two materials are considered, acrylonitrile butadiene styrene and polylactideacid. Wettability, surface morphology and mechanical strength have been determined at different combinations of nozzle temperature, print speed and layer thickness.

The improvement of the fracture toughness of adhesive joints is a key factor in many structural applications. The ability of nylon electrospun nanofibrous mat to act as an adhesive carrier and reinforcing web in adhesive bonding has been demonstrated by the Authors in previous works. It has been shown that the impregnation method developed and refined during the previous studies allow generating high-quality pre-preg nanomats out of a 2k unfilled epoxy resin. By applying this methodology, in the present work, rubbery nanofibrous mats have been adopted for the first time to reinforce and increase the fracture toughness of adhesive joints. Rubbery nanofibers were produced by electrospinning of nitrile butadiene rubber (NBR) and poly(ε-caprolactone) (PCL). The addition of the semi-crystalline polymer (PCL) is exploited to maintain the nanofibrous morphology, which the rubber alone (NBR) would not be able to ensure due to its low glass transition temperature (Tg). The nanofibers thus obtained have been integrated into a two-component high strength epoxy resin for structural applications. S235 steel adherends for Double Cantilever Beam (DCB) tests have been manufactured and sandblasted to improve adhesion. An optimization of the sandblasting parameters (distance, pressure, angle and time) has been carried out evaluating the shear strength and the fracture surfaces on S235 steel Single Lap Joints (SLJ). Finally, DCB tests have been performed to compare the mode I fracture toughness with and without the rubbery electrospun nanomats.

This work is aimed at exploring the feasibility of ultrasonic welding (USW) of a composite laminate made of polycarbonate reinforced with continuous glass fibers, with and without the addition of an energy director (ED) in the form of a neat polycarbonate wire. Welding has been done by varying one factor at a time in order to highlight the dependence of joint strength on each welding parameter. The material has been tested with dynamic mechanical analysis in order to characterize the viscoelastic behavior and temperature dependence. The results in terms of strength show that it is possible to weld also without an ED, but the results using this latter are much better in terms of both average value and standard deviation. The USW joint strength has also been compared with that of adhesive joints, resulting better than this latter when employing the ED, which makes USW a convenient technology for joining this type of composite material. [ABSTRACT FROM AUTHOR]

Carbon-Fiber Reinforced Polymer (CFRP) parts are joined mainly using adhesive bonding because, differently from fastening, additional parts (hence weight saving) and through holes (that are always detrimental for the strength due to the possibility of developing damage into the composite) are not necessary. Additionally, it allows for large connection areas, thus distributing stresses better than fastened connections. However, since CFRP can be joined by co-curing, the choice of bonding has to be evaluated as an alternative by a trade-off in terms of strength and durability, compared to cost and manufacturing time and complexity. In this work, a comparison between co-cured and co-bonded CFRP is done with respect to tensile strength and mode I and mode II fracture toughness, in order to understand whether cobonding guarantees the same performance of a co-cured composite part

The purpose of this work is to compare the co-bonding vs. cold-bonding route on the adhesive joint performance of a CFRP (Carbon Fiber Reinforced Polymer) laminate–aluminum connection. In particular, the overlap shear, tensile strength and Mode I and Mode II fracture toughness will be evaluated. The adhesives for co-bonding and cold-bonding are, respectively, a thermosetting modified epoxy, unsupported structural film and a two-component epoxy adhesive, chosen as representative of applications in the high-performance/race car field. The emerging trend is that, in tensile e Mode I fracture tests, the failure path is predominantly in the composite. Mode II fracture tests instead resulted in a cohesive fracture, meaning that, under pure shear loading, the weakest link may not be the composite. The lap-shear tests are placed midway (cohesive failure for co-bonding and composite delamination for cold-bonding, respectively), probably due to the different peel stress values related to the different adhesive Young’s modulus. The exploitation of the full capacity of the adhesive joint, hence the possibility of highlighting better, different performances of co-bonding vs. cold-bonding, would require consistent improvement of the out-of-plane strength of the CFRP laminate and/or to someway redistribute the peel stress on the bondline.

Adhesive bonding is the elective joining system between Carbon-Fiber Reinforced Polymer (CFRP) parts because, with respect to fastening, it allows a large connection area, no additional parts (hence weight saving) and no need to drill holes into the composite, that is always detrimental for the strength due to the possibility of developing damage. However, the choice of bonding CFRP should be evaluated as alternative to direct curing in terms of strength and durability, compared to cost and manufacturing time and complexity. In this work, a comparison between co-cured and co-bonded CFRP is done with respect to tensile strength and mode I and mode II fracture toughness, in order to understand whether co-bonding guarantees the same performance of a co-cured composite part.Adhesive bonding is the elective joining system between Carbon-Fiber Reinforced Polymer (CFRP) parts because, with respect to fastening, it allows a large connection area, no additional parts (hence weight saving) and no need to drill holes into the composite, that is always detrimental for the strength due to the possibility of developing damage. However, the choice of bonding CFRP should be evaluated as alternative to direct curing in terms of strength and durability, compared to cost and manufacturing time and complexity. In this work, a comparison between co-cured and co-bonded CFRP is done with respect to tensile strength and mode I and mode II fracture toughness, in order to understand whether co-bonding guarantees the same performance of a co-cured composite part.

The study is aimed at developing a modular lattice base for automatic food machines, starting with a solution already patented by some of the authors. In this case, welded carpentry modules were interlocked with a system of profiles and metal inserts, also in welded carpentry, and the union was stabilized by structural adhesive bonding. Since welding involves long processing times and thermal distortions to be restored later, the driver of this study is to limit the use of welding as much as possible while increasing the modularity of the construction. For this purpose, various solution concepts have been generated where a common feature is the presence of rods of the same geometry and section to be joined together in configurable structural nodes. The concepts are qualitatively evaluated in light of the requirements, and the selected concept is digitally and physically prototyped. The prototype has been in service from over 5 years without showing any problems whatsoever.