bluuebunny/crossref_metadata_2025_split huggingface dataset:
A test method for manufacturing effect assessment in HCF
Authors: Beghini M , Bertini L , Macoretta G , Monelli B D , Arcioni M , Bagattini A , Grilli M , Tognarelli L 
Published: March 2021

Abstract
Surface conditions produced by manufacturing processes are known to significantly affect the fatigue strength of metallic materials. However, fatigue tests on planar specimens usually present the onset of fatigue crack in a specimen edge, where the superposition of different machining techniques and subsequent machining operations can hide the effects of the studied process. This study deals with the design of a fatigue test able to reliably assess the effects on the high cycle fatigue strength of any machining process used to produce planar surfaces. It was devised a test configuration where the specimen geometry and the loading conditions are aimed to locate the crack nucleation in the middle of the surface machined by the investigated process. This condition is achieved by employing a notched specimen and a three-point bending test configuration, where the position and geometry of the notches are designed to relieve the specimen’s edges. Nevertheless, in the critical region, the stress state is quite uniaxial and uniform in the longitudinal direction. The specimen is manufactured by using the same parameters and processes adopted for full-scale components, thus producing a surface with the same properties as the real component. The designed test configuration was validated in a high cycle fatigue test aimed to compare the effects of broaching and wire electrical discharge machining on the Wöhler curve (S-N curve). The specimen geometry was tailored for a broaching process so that it has sufficient stiffness both in the directions parallel and perpendicular to the broaching direction. Fatigue tests were carried out on a resonant machine, that allowed to detect the crack nucleation by monitoring the test frequency.
Thermographic-DIC approach in fatigue behaviour analysis
Authors: Barbagallo R , Fargione G , Giudice F , La Rosa G 
Published: March 2021

AbstractA research program was carried out by a group of researchers of nine Italian universities in order to define the fatigue parameters of a commercial steel. The purpose is to define the fatigue limits in different loading conditions and comparing the results obtained by tests performed using different energetic methodologies. In this paper the thermographic method already proposed in literature was performed, determining the Haigh and Goodman-Smith limit curves. At the same time, the thermal response in static tests were derived in order to correlate the limit of the totally thermoelastic behaviour.
Acoustic Emission Techniques for Evaluating Damage Modes in CFRP Hybrid Joints
Authors: Barile C , Casavola C , Pappalettera G , Vimalathithan PK 
Published: March 2021

Abstract
The Acoustic Emission (AE) technique is one of the powerful Non-Destructive Evaluation (NDE) tools for predicting and assessing damages in composite structures. In this research work, the energy released during each acoustic event, as a function of the total number of counts, is used for evaluating the damage modes in CFRP hybrid joints. The damage modes identified using the AE parameter, Energy per Count (

E

A
E

n

) is compared with the waveforms of the acoustic events. Generally, the type of damage mode can be identified by postprocessing the acoustic waveforms. By comparing the waveforms with the

E

A
E

n

, the damage mode has been evaluated. The technique introduced in this work will reduce the data storage and computation time for analyzing the waveforms. The damage modes can be identified during loading using this technique. In addition to that, the location of the generated acoustic events is used for identifying the critical failure areas in the CFRP hybrid joints. The attenuation of the AE events due to the distance between the sensors and the AE source is also considered for this study. From the observed results, the AE technique proves to be one of the formidable techniques for evaluating damage modes in composite structures.
Biomechanical evaluation of titanium trabecular sphere in kyphoplasty procedure
Authors: Krüger A , Francaviglia N , Di Bella S , Mineo R 
Published: March 2021

AbstractThe treatment of osteoporotic vertebral compression fractures using transpedicular augmentation has grown significantly during the past two decades. Balloon Kyphoplasty allowed to restore vertebral height and to improve the deformity, but has several disadvantages related to the filler material used: the bio-cement. The aim of the current study is to investigate the mechanical behaviour of cadaveric fractured osteoporotic vertebral treated with a new filler material made by Spheres in Trabecular Titanium alloy (Ti6Al4V-ELI), under static loading conditions. The Strength of the VBs remain almost the same. So, the VBs maintain their physiological values after the kyphoplastic procedure with trabecular titanium sphere. The stiffness was instead significantly reduced in some VBs. This data can be affected to the limit of ex vivo study.
Influence of infill percentage on the mode I fracture toughness of adhesively bonded Double Cantilever Beam joints with Additively Manufactured PLA adherends
Authors: Moroni F , Pirondi A , Bergonzi L , Vettori M 
Published: March 2021

Abstract
Adhesive bonding can disclose the possibility to additively manufacture (AM) smaller, highly optimized objects to be bonded in post-production into/onto larger components. However, the infill shape and percentage can influence the fracture toughness of a bonded joint as it emerges from the literature Since the choice of the infill yields also a significant impact on manufacturing time, it is important to assess clearly its influence on bonded joint strength in order to balance strength and manufacturing issues. Therefore, in this work the Mode I fracture toughness of PLA bonded joints obtained by FFF will be assessed as a function of infill percentage, from solid (100% infill) to 20% infill. Test will be done using a Double Cantilever Beam (DCB) joint bonded with a PolyUrethane (PU), room temperature-curing adhesive.
On the use of shape memory alloys for deployable passive heat radiators in space satellites
Authors: Bacciotti A , Bucchi F , Frendo F , Mameli M , Perna R , Filippeschi S 
Published: March 2021

AbstractThe present work presents a multifunctional structure for space engineering application part of the TOPDESS project, funded by ESA.The main aim of the project is the design of a thermal control device able to deploy through passive actuation. A combined device has been designed, made up of a Pulsating Heat Pipe (PHP) foldable heat exchanger and Shape Memory Alloy (SMA) wire. The deployment of the SMA wire is conceived to be controlled by thermal contact with the heat source and by conduction along the wire. Since the heat sources are lumped and the wire is subject to convection, a temperature gradient develops along the wire.A monodimensional mode able to predict the behavior of an SMA wire subjected to a spatial temperature gradient, is presented in this paper.The results show that the system can carry out folding and unfolding cycles with rotation angles greater than 80° only if the wire is subjected to uniform temperature distribution; in the case of temperature gradient, the achievable rotation angle is about 20°.The analysis states the feasibility of the actuation system, highlighting the critical technological aspects, to lay the groundwork for the future development of the whole system.
Laser Powder Bed Fusion: A Review on the Design Constraints
Authors: Ceccanti F , Giorgetti A , Arcidiacono G , Citti P 
Published: March 2021

Abstract
With the creation of additive manufacturing production lines and the adoption of additive technologies, such as Laser Powder Bed Fusion, as standard manufacturing technologies for the mass production of parts, many considerations arise. In particular, product quality assurance is surely a very important aspect to be considered when talking about mass production. Laser powder bed fused parts are characterized by specific characteristics, such as quite rough surfaces and internal cavities filled with powder after the part construction. The need to ensure part quality and the importance to guarantee quality to all the parts made within the production line highlights the need to design the part addressing all the criticalities resulting from the manufacturing process, in addition to the ones related to the operative conditions. In this work, the attention is placed on two important topics: part surface inspectability and part cleaning. In particular, part inspectability is a crucial aspect in determining part coherence with design specifications. Part production via LPBF puts interpretability issues in inspecting the parts. Part cleaning is a crucial topic as well. Part cleaning is related to the design of the part to guarantee a correct powder evacuation from all the internal channels and cavities. Within the work, problems will be defined and design guidelines will be proposed to manage these topics.
Experimental validation of miniaturized specimen developed to perform uniaxial tensile test on high performance materials
Authors: Bergonzi L , Vettori M , Moroni F , Musiari F , Pirondi A 
Published: March 2021

Abstract
This work deals with the experimental validation of the proposed specimens geometries which design process through Finite Element Method was presented during AIAS 2019 and published afterwards [1]. In particular, non-conventional miniaturized specimen geometry compliant to ASTM E8 and ISO 6892, specifically developed to work with MaCh3D [2], an innovative miniaturized tensile testing machine, were considered. The size-reduction of specimens is advantageous both in terms of material and equipment: smaller specimens require lower forces to be broken, hence a compact tensile testing machine can perform the mechanical characterization activity. In this experimental validation, mechanical properties determined using the three proposed MaCh3D miniaturized specimens are compared to full-size ISO 6892 samples. Specimens were cut from AISI 304 stainless steel plates, with different thickness according to specimens requirements. Good accordance has been found between the standard and non-standard geometries.
Analysis of belt transmissions capabilities using the brush model
Authors: Bucchi F , Frendo F 
Published: March 2021

Abstract
The mechanics of power transmission is usually modeled by two different theories: the creep theory and the shear theory. Recently, the authors introduced an alternative theory based on the brush model, which allows to compute the tangential stress distribution along the winding arc of pulleys. The brush model is able to predict the speed loss along the driving and driven pulley as a function of the transmission parameters (e.g. pre-load, friction, pulley radii etc.) and the operating parameters (i.e. angular speed and resistant torque). In addition, the energy efficiency of the system is obtained by knowing the speed loss and the energy dissipation; this contribution can be subdivided into energy loss due to friction and energy loss due to the non-recoverable elastic deformation of the bristle.
In the present paper, using the previously developed model, a sensitivity analysis aimed at mapping the transmission capabilities as a function of geometry and operating parameters is proposed. These results, given as look-up table (or contour plot), are very important in mechanical systems simulation (e.g. real-time systems, hardware in the loop systems) since they allow to introduce the phenomenological behavior of the pulley-belt transmission without introducing complex models in the simulation.
Experimental modal analysis of SSR1 cryomodule for numerical model tuning and validation
Authors: Barnaba A , Bucchi F , Neri P , Passarelli D 
Published: March 2021

Abstract
The present activity aims to test the Cryomodule SSR1 to validate the corresponding mixed multibody-finite element numerical model and to determine the range of frequencies in which the first natural modes of the structure lie. The experimental activity consisted of a hammer test of the cryomodule at an early assembly stage at which the internal parts, constituting the cold mass, are accessible and, thus, many accelerometers can be attached to the beam string. The comparison between the experimental results obtained for the sub-assembly and the numerical results obtained for the corresponding sub-model, derived from the previously developed complete model, allowed to assess the validity of the numerical model and to get feedback on the effectiveness of the placement of the sensors in capturing the dynamic response of the system during transportation.
Influence of design parameters on the penetration resistance of machine guards
Authors: Landi L , Vittori M , Stecconi A , Valigi M C 
Published: March 2021

Abstract
In the last years, different research on ballistic penetration of machine tools guards, as defined in EU Directive 2006/42/EC, were conducted in different worldwide laboratories. Even if the design of machine safety guards using the material/thickness are defined in annexes of ISO standardization, a revision of those annexes is expected in next years. Standardized tests have some limitations because they are performed using a given penetrator that impacts perpendicularly the surface of flat plates of about 500 mm x 500 mm. In this paper the influence of some design parameters will be investigated by polycarbonate sheets of 4mm thickness. The evaluation of ballistic limit for 4 mm sheets of 300 mm x 300 mm and 500 mm x 500 mm size will be presented. Moreover, the influence of constraint on ballistic limit of standardized 500 mm x 500 mm sheets will be also presented by two different constraint devices: one similar to a border hinge constraint, one to a border rigid clamping. Discussion of results will be presented with a view to review the ISO standardization annexes on ballistic penetration.
Defining Double Capsules: A Clinical and Histological Study
Authors: Van Slyke Aaron C , Roller Janine M , Alaghehbandan Reza , Carr Nicholas J 
Published: March 2021

Abstract

Background
Macrotextured breast implants are associated with double capsules. There is little agreement as to what defines double capsules, how they present, and whether different degrees of double capsule exist.

Objectives
This study aimed to define double capsules and report an association between double-capsule type and degree of tissue adherence.

Methods
Consecutive aesthetic patients undergoing explantation of Biocell (Allergan, Inc., Irvine, CA) implants between May 2018 and November 2018 were included if they were found to have double capsules intraoperatively. Patient demographics, implant characteristics, explantation reason, implant adherence, and intraoperative findings were recorded. Both adherent and double capsules were histologically examined. Data were analyzed by descriptive statistics.

Results
Eleven patients had 22 Biocell implants explanted during the study period. The average explantation time was 8.0 years. Sixteen implants were found to have some degree of nonadherence, and all areas of nonadherence were associated with double-capsule formation. Double capsules were either partial or complete. The architecture of the inner layer of double capsules varied between an organized capsular layer and a thin area of nascent capsule. Histologically, all capsular specimens demonstrated an overall hypocellular fibrous capsule with scattered chronic inflammatory infiltrates. Synovial metaplasia was present in all capsule types and spaces/cracks in the capsule were disproportionately represented in partially adherent capsules.

Conclusions
This is the first study to identify a clinical and pathological correlation between double capsules and failed tissue adherence. Double capsules represent a spectrum of inner capsule formation ranging between nascent capsular tissue to a mature inner capsular layer.

Level of Evidence: 4
Mid-rotation variation in growth, form and phenology of sycamore (Acer pseudoplatanus L.) provenances in field trials in England
Authors: Whittet Richard , Lopez Gustavo , Rosique-Esplugas Cristina 
Published: March 2021

Abstract
Field trials containing 8–10 sycamore seed sources were established on ‘farm woodland’ sites in 1992 to identify the most productive and adapted seed sources for use in lowland Great Britain. Early results from these trials found little difference among provenances for growth traits. To guide the next steps of sycamore improvement in the British Isles, three of the five original trials have been revisited and assessed for variation in growth and form at 27 years, which is between one-third and half rotation age. There were large differences in growth among sites but differences among provenances were small or non-significant and showed no interaction across sites. Spring phenology evaluation from one of the trials demonstrated that timing of bud burst was negatively associated with latitude which was the only trait providing any evidence of adaptive differentiation among provenances. However, the effect was small and driven by much later flushing of French and German seed sources than British seed sources. Given the lack of clear provenance differentiation and qualitatively similar rankings across sites, we found no justification for subdividing Britain into breeding zones for sycamore at this stage, nor for excluding material from mainland Europe in planned progeny tests.
Remote Delivery of Thrombolytics Prior to Transfer to a Regional Burn Center for Tissue Salvage in Frostbite: A Single-center Experience of 199 Patients
Authors: Carmichael Heather , Michel Samuel , Smith Tyler M , Duffy Patrick S , Wiktor Arek J , Lambert Wagner Anne 
Published: March 2021

Abstract
While much has been published on the efficacy and safety of systemic thrombolytics in the treatment of acute frostbite, there has been limited investigation into administration outside a tertiary care setting. Here, we present a single-center experience with remote initiation of intravenous tissue plasminogen activator (tPA) at referring hospitals prior to transfer to a regional burn center. A modified Hennepin Quantification Score based on tissue involvement was used to determine eligibility for tPA and to quantify the severity of amputation. This is a retrospective review of patients with acute frostbite of the digits admitted to a single verified burn center over a 5-yr period. Of 199 patient admissions, 40 received tPA remotely pre-transfer, 32 received tPA on admission to our institution, and 127 patients did not qualify for tPA therapy according to the protocol. Comparing patients who required any amputation (n = 99, 49.7%) to those who did not, patients who received remote tPA had lower odds of any amputation compared to both those receiving tPA at our institution (OR 0.19, 95% CI 0.05–0.65, P = 0.01) and the group receiving no tPA (OR 0.14, 95% CI 0.05–0.40, P &lt; 0.001) after controlling for confounders. Only one patient receiving pre-transfer tPA according to the protocol (2.3%) had a significant bleeding event requiring transfusion. These results support the protocolized use of thrombolytic therapy for frostbite prior to transfer to a tertiary center.
Anterior leaflet replacement and reconstruction with Admedus Cardiocel™ decellularized pericardial patch in tricuspid valve endocarditis
Authors: Mohamed Saifullah , Patel Akshay J , Mazhar Khurum , Jeeji Ravish , Ridley Paul D , Balacumaraswami Lognathen 
Published: March 2021

ABSTRACT
We present the case of a 28 year-old lady with a history of intravenous drug use who presented to our institution with symptomatic right heart failure secondary to tricuspid valve regurgitation. She presented with infective endocarditis leading to dyspnoea and peripheral oedema secondary to torrential tricuspid regurgitation. Transthoracic echocardiography confirmed right ventricular dysfunction and congestive hepatomegaly. Intra-operatively findings an infected and destroyed anterior leaflet of the tricuspid valve with posterior leaflet prolapse was found to cause severe tricuspid regurgitation. She had complex tricuspid valve reconstruction using anterior leaflet reconstruction using Admedus Cardiocel™ patch, posterior leaflet prolapse correction and commissural reduction with a McGoon imbrication and annuloplasty ring to stabilize the repair. This case demonstrates the importance of reconstructive tricuspid valve surgery in the setting of infective endocarditis. Furthermore, this case demonstrates the possibility of anterior leaflet excision and reconstruction with an excellent durable functional result.
Hemorrhage Following Complete Arteriovenous Malformation Resection With No Detectable Recurrence: Insights From a 27-Year Registry
Authors: Rapaport Sarah , Feghali James , Yang Wuyang , Gami Abhishek , Patel Jaimin , Tamargo Rafael J , Caplan Justin M , Huang Judy 
Published: March 2021

Abstract

BACKGROUND
Although recurrence and de novo formation of arteriovenous malformations (AVMs) have been reported following complete resection, the occurrence of hemorrhage in the same location of an AVM with no detectable lesion (lesion-negative hemorrhage) has not been described after microsurgery.

OBJECTIVE
To characterize the incidence and properties of lesion-negative hemorrhage following complete microsurgical resection

METHODS
A prospectively maintained registry of AVM patients seen at our institution between 1990 and 2017 was used. Microsurgically treated patients were selected, and the incidence of a lesion-negative hemorrhage was calculated and described with a Kaplan-Meier curve. Baseline characteristics as well as functional outcome at last follow-up were compared between patients with and without a lesion-negative hemorrhage.

RESULTS
From a total of 789 AVM patients, 619 (79%) were treated, and 210 out of 619 patients (34%) underwent microsurgery with or without preoperative embolization or radiosurgery. The microsurgically treated cohort was followed up for a mean of 6.1 ± 3.0 yr after surgery with 5 (2.4%) patients experiencing postresection lesion-negative hemorrhage (3.9 per 1000 person-years) at an average of 8.6 ± 9.0 yr following surgery. Follow-up angiograms after hemorrhage (up to 2 mo posthemorrhage) confirmed the absence of a recurrent or de novo AVM in all cases. All patients with a lesion-negative hemorrhage initially presented with rupture before resection (Fisher P = .066; log-rank P = .057). The occurrence of a lesion-negative hemorrhage was significantly associated with worse modified Rankin scale scores at last follow-up (P = .031).

CONCLUSION
A lesion-negative hemorrhage can occur following complete microsurgical resection in up to 2.4% of patients. Exploration of possible underlying causes is warranted.