bluuebunny/crossref_metadata_2025_split huggingface dataset:
Design of Compliant Joints for Large Scale Structures
Authors: Nastevska Angela , Jovanova Jovana , Frecker Mary 
Published: November 2020

Abstract
Large scale structures can benefit from the design of compliant joints that can provide flexibility and adaptability. A high level of deformation is achieved locally with the design of flexures in compliant mechanisms. Additionally, by introducing contact-aided compliant mechanisms, nonlinear bending stiffness is achieved to make the joints flexible in one direction and stiff in the opposite one. All these concepts have been explored in small scale engineering design, but they have not been applied to large scale structures. In this paper the design of a large scale compliant mechanism is proposed for novel design of a foldable shipping container. The superelasticity of nickel titanium is shown to be beneficial in designing the joints of the compliant mechanism.
Development and Experimental Demonstration of a Shape Memory Alloy-Based Adaptive Two-Phase Radiator for Space Applications
Authors: Lilly Jared , Hansen Bethany , Lotz Ryan , Hartl Darren , Cognata Thomas , Nizio Priscilla , Joyce Connor 
Published: November 2020

Abstract
Future space exploration, such as the Artemis program, journeys to Mars, and future lander missions will require thermal control systems (TCSs) with the ability to adapt to a wide range of thermal loads due to vastly fluctuating external temperatures. Current TCSs employ radiators that can achieve a turndown ratio (defined as the ratio of the maximum to minimum heat rejection rates) of 12:1 by utilizing regenerative heat exchangers and a two-fluid-loop system, both of which are heavy and complex. However, future missions will demand radiators that can provide turndown ratios of 12:1 while remaining light, functionally passive, and simply designed. Previous work has investigated using shape memory alloy (SMA) components in single phase radiator prototypes to achieve efficient heat rejection. Preliminary analysis shows that SMA-based radiators can enable turndown ratios as high as 37:1. In this paper, the design, fabrication, and testing of an SMA torque tube driven radiator prototype is discussed. The SMA torque tube is attached to a heat rejecting panel that resembles flat radiator panels currently installed on the International Space Station. As the temperature of the working fluid in the TCS increases, the SMA torque tube actuates and rotates the panel, allowing for more radiative heat rejection to occur. This new design matures the concept past a previous prototype that merely demonstrated actuation under single-phase (e.g., liquid water) flow. The current radiator prototype has been designed to function not only with closed-loop, single-phase fluid flow, but also in conjunction with a two-phase TCS and even as a heat pipe. Both approaches take advantage of phase transformation of the working fluid to improve overall TCS efficiency and decrease complexity. During testing, a heated two-phase working fluid was circulated through the system, resulting in a maximum angular actuation of 67 degrees, thus demonstrating two-phase operation for the first time. These results give confidence that an SMA torque tube-driven radiator can outperform current radiators as development continues.
Posable Tensegrity-Constrained Inflatable Kinematic Graphical Analysis
Authors: Wihardja Adeline , Patel Kunj , Giner Munoz Laura , Kim Ellen , Luntz Jonathan , Brei Diann , Kim Wonhee , Alexander Paul 
Published: November 2020

Abstract
Inflatable devices have been used in various applications due to their low cost, light weight, simplicity, and ability to compactly stow yet deploy to large sizes with complex shape. Recently, soft robotics has added active shape change to inflatables’ otherwise static functionality. However, the required complex multi-chamber structures and active pressure control sacrifice many inherent advantages including simplicity and stowability. Many applications require only passive shape change (posability), where users manipulate a device manually, and the device simply holds its new posed shape. This paper explores a new approach using internal string-like tensile elements to provide posability while maintaining stowability and other inherent advantages of inflatables, leveraging concepts in the field of tensegrity mechanisms. Tensegrity constrained inflatables provide posable motion by allowing internal tensile strings to thread through loops as the shape is changed, where friction between the strings and loops retain the new pose. Graphical instantaneous center kinematic analysis techniques for traditional linkage systems are extended to include threaded tensegrity mechanisms, enabling analysis and design of complex posable tensegrity structures. A simple example prototype implementing bending with 1 DOF, demonstrates posable behavior, quantified in terms of the force required to change pose at different angles and pressures. The resulting bistable behavior is explained using the IC kinematic analysis. The kinematic techniques are also applied to the design of one degree of freedom functional building blocks which combine to create tensegrity configurations providing 2 DOF posability in two and three dimensions which are demonstrated through multiple hardware prototypes. The novel technology and design methods presented in this paper provide a foundation for the development of a class of new user-interactive inflatable devices with posable functionality and deploy and stow capability.
A Phenomenological Model for Shape Memory Alloys With Uniformly Distributed Porosity
Authors: Zaki Wael , Viet N. V. 
Published: November 2020

Abstract
A phenomenological model is proposed for shape memory alloys considering the presence of uniformly distributed voids. The model is developed within a modified generalized standard materials framework, which considers the presence of constraints on the state variables and ensures thermodynamic consistency. Within this framework, a free energy density is first proposed for the porous material, wherein the influence of porosity is accounted for by means of scalar state variables accounting for damage and inelastic dilatation. By choosing key thermodynamic forces, derived from the expression of the energy, as sub-gradients of a pseud-potential of dissipation, loading functions are derived that govern phase transformation and martensite detwinning. Flow rules are also proposed for damage and inelastic dilatation in a way that ensures positive dissipation. The model is discretized and the integration of the time-discrete formulation is carried out using an implicit formulation, whereby a return mapping algorithm is implemented to calculate increments of dissipative variables including inelastic strains. Comparison with data from the literature is finally presented.
A Fiber Optic Conjugate-Stress Sensor for Prognostic Health Monitoring of Fatigue
Authors: Kordell Jonathan , Yu Miao , Dasgupta Abhijit 
Published: November 2020

Abstract
A fiber optic conjugate stress sensor (FOCSS) is explored for monitoring fatigue in aluminum cantilever beams. It is known that as damage accumulates due to fatigue, microstructural changes result in an altered modulus; so in this work, fatigue is continuously monitored by measuring the evolution of the effective modulus of the host. Conjugate stress sensing extracts host modulus from two extensometers of different stiffnesses (termed the stiff and compliant sensors) by using a known transfer function from sensor strains to host modulus. The sensing concept is explained and the transfer function is determined from a lumped-mass spring model. Finite element modeling is carried out, which reveals the host modulus assessed by the FOCSS is more sensitive to fatigue damage of a structure than its natural frequency (another commonly used macroscale measure of fatigue). The FOCSS capabilities are next verified in aluminum beam fatigue experiments. The FOCSS estimated modulus is seen to decrease with accumulation of fatigue damage. However, fatigue of the glue used to attach the sensors to the specimen is found to obscure the sensor’s response to host fatigue, thus presenting an important source of experimental error. Future work aims to deconvolve FOCSS sensitivity to glue fatigue from the response to host fatigue. Our finite element simulation results indicate that the FOCSS can significantly hasten early warning and extend the prognostic horizon, which can greatly reduce logistical burden and increase consumer confidence.
Automotive Grille Shutter Using Passive Shape Memory Alloy Actuation
Authors: Smith Anthony L. , Kim Wonhee , Brown Jeffrey 
Published: November 2020

Abstract
Automotive grille shutters are used to reduce the aerodynamic drag of the vehicle when cooling requirements are low by blocking a portion of the airflow through the condenser, radiator, and fan module (CRFM); the lower aerodynamic drag improves fuel economy. A passively actuated SMA grille shutter was designed as a less complex and lower overall cost solution to current electro-mechanical designs. This paper presents the design and calibration process for the automotive grille shutter SMA actuator using passive temperature control. The initial design target opening and closing temperatures of the grille shutter system were determined by climatic wind tunnel and vehicle road tests measuring motor-driven grille shutter position versus CRFM exhaust temperature. The initial SMA actuator design almost met the temperature requirements; subsequent road testing confirmed the need to shift the start to close and fully closed temperatures at least 6 °C higher to meet specifications. The transformation temperatures of the SMA actuator were calibrated by varying stress on the SMA wires by means of the total cross-sectional area and biasing force. Tests were performed in an environmental chamber to characterize the temperature-position behavior during heating and cooling cycles, the best candidate improved the hysteresis band by 3 °C from the initial design. This study presents an industry need for the development of lower hysteresis SMA wires/springs for passive applications, which can maximize the benefit of SMA actuation by utilizing the temperature-stress-strain coupling behavior of SMA.
Core outcome set for diabetes after pregnancy prevention across the life span: international Delphi study
Authors: Wu Nancy , O'Reilly Sharleen , Nielsen Karoline Kragelund , Maindal Helle Terkildsen , Dasgupta Kaberi 
Published: November 2020

IntroductionMothers with gestational diabetes mellitus (GDM) are at high risk of future diabetes. An active area of research examines health behavior change strategies in women within 5 years of a GDM pregnancy to prevent diabetes after pregnancy. We aimed to develop a core outcome set (COS) to facilitate synthesis and comparison across trials.Research design and methodsCandidate outcomes were identified through systematic review and scored for importance (1–9) by healthcare professionals, researchers, and women with prior GDM through an international two-round electronic-Delphi survey. Outcomes retained required round two scores above prespecified thresholds (≥70% scoring 7–9) or expert panel endorsement when scores were indeterminate. The panel organized the COS by domain.Results115 stakeholders participated in the survey and 56 completed both rounds. SD of scores decreased by 0.24 (95%CI 0.21 to 0.27) by round 2, signaling convergence. The final COS includes 19 domains (50 outcomes): diabetes (n=3 outcomes), other related diseases (n=3), complications in subsequent pregnancy (n=2), offspring outcomes (n=3), adiposity (n=4), cardiometabolic measures (n=5), glycemia (n=3), physical activity (n=2), diet (n=4), breast feeding (n=2), behavior change theory (n=5), diabetes-related knowledge (n=2), health literacy (n=1), social support (n=1), sleep (n=1), quality of life (n=1), program delivery (n=4), health economic evaluation (n=2), and diabetes risk screening (n=2). The seven outcomes endorsed by ≥90% were diabetes development and GDM recurrence, attending the postpartum diabetes screening and completing oral glucose tolerance testing and/or other glycemia measures, weight and total energy intake, and health behaviors in general. Among the 15 at the 80%–90% endorsement level, approximately half were specific elements related to the top 7, while the remainder related to diabetes knowledge, personal risk perception, motivation for change, program element completion, and health service use and cost.ConclusionResearchers should collect and report outcomes from the breadth of domains in the COS.
Chest drain aerosol generation in COVID-19 and emission reduction using a simple anti-viral filter
Authors: Duffy Clodagh , Kidd Andrew , Francis Sarah , Tsim Selina , McNaughton Laura , Ferguson Katie , Ferguson Jenny , Rodgers K Gary , McGroarty Claire , Sayer Robin , Blyth Kevin G 
Published: November 2020

IntroductionThe COVID-19 pandemic has been characterised by significant in-hospital virus transmission and deaths among healthcare workers. Sources of in-hospital transmission are not fully understood, with special precautions currently reserved for procedures previously shown to generate aerosols (particles <5 μm). Pleural procedures are not currently considered AGPs (Aerosol Generating Procedures), reflecting a lack of data in this area.MethodsAn underwater seal chest drain bottle (R54500, Rocket Medical UK) was set up inside a 60-litre plastic box and connected via an airtight conduit to a medical air supply. A multichannel particle counter (TSI Aerotrak 9310 Aerosol Monitor) was placed inside the box, allowing measurement of particle count/cubic foot (pc/ft3) within six channel sizes: 0.3–0.5, 0.5–1, 1–3, 3–5, 5–10 and >10 μm. Stabilised particle counts at 1, 3 and 5 L/min were compared by Wilcoxon signed rank test; p values were Bonferroni-adjusted. Measurements were repeated with a simple anti-viral filter, designed using repurposed materials by the study team, attached to the drain bottle. The pressure within the bottle was measured to assess any effect of the filter on bottle function.ResultsAerosol emissions increased with increasing air flow, with the largest increase observed in smaller particles (0.3–3 μm). Concentration of the smallest particles (0.3–0.5 μm) increased from background levels by 700, 1400 and 2500 pc/ft3at 1, 3 and 5 L/min, respectively. However, dispersion of particles of all sizes was effectively prevented by use of the viral filter at all flow rates. Use of the filter was associated with a maximum pressure rise of 0.3 cm H2O after 24 hours of flow at 5 L/min, suggesting minimal impact on drain function.ConclusionA bubbling chest drain is a source of aerosolised particles, but emission can be prevented using a simple anti-viral filter. These data should be considered when designing measures to reduce in-hospital spread of SARS-CoV-2.
Neuroendocrine tumours of the breast: a genomic comparison with mucinous breast cancers and neuroendocrine tumours of other anatomic sites
Authors: Pareja Fresia , Vahdatinia Mahsa , Marchio Caterina , Lee Simon S K , Da Cruz Paula Arnaud , Derakhshan Fatemeh , da Silva Edaise M , Selenica Pier , Dopeso Higinio , Chandarlapaty Sarat , Wen Hannah Y , Vincent-Salomon Anne , Brogi Edi , Weigelt Britta , Reis-Filho Jorge S 
Published: November 2020

AimsBreast neuroendocrine tumours (NETs) constitute a rare histologic subtype of oestrogen receptor (ER)-positive breast cancer, and their definition according to the WHO classification was revised in 2019. Breast NETs display histologic and transcriptomic similarities with mucinous breast carcinomas (MuBCs). Here, we sought to compare the repertoire of genetic alterations in breast NETs with MuBCs and NETs from other anatomic origins.MethodsOn histologic review applying the new WHO criteria, 18 breast tumours with neuroendocrine differentiation were reclassified as breast NETs (n=10) or other breast cancers with neuroendocrine differentiation (n=8). We reanalysed targeted sequencing or whole-exome sequencing data of breast NETs (n=10), MuBCs type A (n=12) and type B (n=11).ResultsBreast NETs and MuBCs were found to be genetically similar, harbouring a lower frequency ofPIK3CAmutations, 1q gains and 16q losses than ER-positive/HER2-negative breast cancers. 3/10 breast NETs harboured the hallmark features of ER-positive disease (ie,PIK3CAmutations and concurrent 1q gains/16q losses). Breast NETs showed an enrichment of oncogenic/likely oncogenic mutations affecting transcription factors compared with common forms of ER-positive breast cancer and with pancreatic and pulmonary NETs.ConclusionsBreast NETs are heterogeneous and are characterised by an enrichment of mutations in transcription factors and likely constitute a spectrum of entities histologically and genomically related to MuBCs. While most breast NETs are distinct from ER-positive/HER2-negative IDC-NSTs, a subset of breast NETs appears to be genetically similar to common forms of ER-positive breast cancer, suggesting that some breast cancers may acquire neuroendocrine differentiation later in tumour evolution.
Birth order is associated with an increased risk of obesity in young adults in Thailand
Authors: Aurpibul Linda , Butler Éadaoin M , Wongthanee Antika , Rerkasem Amaraporn , Pruenglampoo Sakda , Mangklabruks Ampica , Rerkasem Kittipan , Derraik José G B 
Published: November 2020

BackgroundThere is a growing body of evidence showing that early life events are associated with increased risk of cardiovascular and metabolic diseases later in adult life. However, there is a paucity of data in this field from Asian populations. In this study, we examined the association of birth order with obesity risk and cardiometabolic outcomes in young adults in Thailand.MethodsParticipants were the offspring from a birth cohort study in Chiang Mai (northern Thailand), who were followed up at ~20.5 years of age. Clinical assessments included anthropometry, blood pressure, fasting blood samples and carotid intima-media thickness. Insulin sensitivity was estimated using homeostatic model assessment of insulin resistance (HOMA-IR). Participants were stratified into two groups: first-borns and later-borns. Health outcomes between groups were compared using multivariable models adjusting for important confounders, in particular maternal body mass index (BMI).ResultsA total of 559 participants were studied: 316 first-borns (46% males) and 243 later-borns (47% males). Adjusted models showed anthropometric differences, with first-borns being 2.3 kg heavier (p=0.023) with a BMI 0.86 kg/m2greater (p=0.019) than later-borns. Thus, rates of obesity were higher in first-borns than in later-borns (6.6% vs 2.9%), so that first-borns had an adjusted relative risk of obesity 3.3 times greater than later-borns [95% CI 1.42 to 7.88; p=0.006]. There were no observed differences in cardiovascular or metabolic parameters assessed, including HOMA-IR.ConclusionAs observed in other populations, first-borns in Thailand had greater BMI and an increased risk of obesity in young adulthood. However, we observed no other cardiometabolic differences between first- and later-borns.
Rheumatologists’ perspective on hydroxychloroquine guidelines
Authors: Winebrake James , Khalili Leila , Weiner Julia , Gartshteyn Yevgeniya , Park Lisa , Askanase Anca D 
Published: November 2020

ObjectiveHydroxychloroquine (HCQ) retinal toxicity is an ongoing concern for rheumatologists. The revised 2016 American Academy of Ophthalmology (AAO) guidelines created controversy regarding the correct dosing and evaluation of HCQ toxicity. The current study was initiated to further understand rheumatologists’ practices regarding HCQ.MethodsA questionnaire-based survey was distributed electronically to rheumatologists. We collected information on HCQ dosing, clinical decision-making processes, familiarity with the AAO 2016 guidelines, and perceived disparities between the AAO 2016 guidelines and rheumatological clinical practice.Results78 rheumatologists completed the survey (49% from USA, 90% academic practices, 82% self-identified as lupus experts). Only lupus expert (n=64) data were included in subsequent analysis. The mean cohort size was 747 (50–6571), a total cohort 45 612 patients. HCQ was prescribed to >75% of patients with SLE by 81.3% of SLE experts, with routine counselling about ophthalmic risks. The typical dose of HCQ used was 200–400 mg/day. 17% of rheumatologists use doses up to 600 mg/day, while 6.2% use up to 6.5 mg/kg/day. HCQ adherence is routinely assessed. 479 cases of HCQ retinal toxicity (1.05%) and 9 cases of HCQ-associated blindness (1.8 per 10 000 patients) were reported. 89.1% of respondents reported familiarity with the AAO guidelines. Those aware of the guidelines cited limited dosing options (54.7%), lack of supporting evidence (57.8%) and low patient adherence (43.8%) as obstacles to greater implementation of the guidelines.ConclusionThese data suggest that HCQ toxicity and blindness are rare in patients with SLE. Rheumatologists treating patients with SLE are aware of the guidelines and appreciate the importance of partnering with ophthalmologists in preventing retinal toxicity.
Single-Cell Transcriptomic Heterogeneity in Invasive Ductal and Lobular Breast Cancer Cells
Authors: Chen Fangyuan , Ding Kai , Priedigkeit Nolan , Elangovan Ashuvinee , Levine Kevin M. , Carleton Neil , Savariau Laura , Atkinson Jennifer M. , Oesterreich Steffi , Lee Adrian V. 
Published: November 2020

Abstract

Invasive lobular breast carcinoma (ILC), one of the major breast cancer histologic subtypes, exhibits unique features compared with the well-studied ductal cancer subtype (IDC). The pathognomonic feature of ILC is loss of E-cadherin, mainly caused by inactivating mutations, but the contribution of this genetic alteration to ILC-specific molecular characteristics remains largely understudied. To profile these features transcriptionally, we conducted single-cell RNA sequencing on a panel of IDC and ILC cell lines, and an IDC cell line (T47D) with CRISPR-Cas9–mediated E-cadherin knockout (KO). Inspection of intracell line heterogeneity illustrated genetically and transcriptionally distinct subpopulations in multiple cell lines and highlighted rare populations of MCF7 cells highly expressing an apoptosis-related signature, positively correlated with a preadaptation signature to estrogen deprivation. Investigation of E-cadherin KO–induced alterations showed transcriptomic membranous systems remodeling, elevated resemblance to ILCs in regulon activation, and increased sensitivity to IFNγ-mediated growth inhibition via activation of IRF1. This study reveals single-cell transcriptional heterogeneity in breast cancer cell lines and provides a resource to identify drivers of cancer progression and drug resistance.

Significance:
This study represents a key step towards understanding heterogeneity in cancer cell lines and the role of E-cadherin depletion in contributing to the molecular features of invasive lobular breast carcinoma.