bluuebunny/crossref_metadata_2025_split huggingface dataset:
Machine Learning for Predicting the Critical Yield Stress of High Entropy Alloys
Authors: Vilalta Pau Cutrina , Sheikholeslami Somayyeh , Saleme Ruiz Katerine , C. Yee Xin , Koslowski Marisol 
Published: October 2020

Abstract
We applied machine learning models to predict the relationship between the yield stress and the stacking fault energies landscape in high entropy alloys. The data for learning in this work were taken from phase-field dislocation dynamics simulations of partial dislocations in face-centered-cubic metals. This study was motivated by the intensive computation required for phase-field simulations. We adopted three different ways to describe the variations of the stacking fault energy (SFE) landscape as inputs to the machine learning models. Our study showed that the best machine learning model was able to predict the yield stress to approximately 2% error. In addition, our unsupervised learning study produced a principal component that showed the same trend as a physically meaningful quantity with respect to the critical yield stress.
Flow Pattern Transition in Pipes Using Data-Driven and Physics-Informed Machine Learning
Authors: Quintino André M. , da Rocha Davi L. L. N. , Fonseca Jr. Roberto , Rodriguez Oscar M. H. 
Published: October 2020

Abstract
Flow pattern is an important engineering design factor in two-phase flow in the chemical, nuclear and energy industries, given its effects on pressure drop, holdup, and heat and mass transfer. The prediction of two-phase flow patterns through phenomenological models is widely used in both industry and academy. In contrast, as more experimental data become available for gas-liquid flow in pipes, the use of data-driven models to predict flow-pattern transition, such as machine learning, has become more reliable. This type of heuristic modeling has a high demand for experimental data, which may not be available in some industrial applications. As a consequence, it may fail to deliver a sufficiently generalized transition prediction. Incorporation of physics in machine learning is being proposed as an alternative to improve prediction and also to reduce the demand for experimental data. This paper evaluates the use of hybrid-physics-data machine learning to predict gas-liquid flow-pattern transition in pipes. Random forest and artificial neural network are the chosen tools. A database of experiments available in the open literature was collected and is shared in this work. The performance of the proposed hybrid model is compared with phenomenological and data-driven machine learning models through confusion matrices and graphics. The results show improvement in prediction performance even with a low amount of data for training. The study also suggests that graphical comparison of flow-pttern transition boundaries provides better understanding of the performance of the models than the traditional metric
Synergistic Flow-Induced Oscillation of Multiple Cylinders in Harvesting Marine Hydrokinetic Energy
Authors: Li Mengyu , Bernitsas Christopher C. , Guo Jing , Sun Hai 
Published: October 2020

AbstractFlow-induced oscillations/vibrations (FIO/V) of cylinders in tandem can be enhanced by proper in-flow spacing to increase hydrokinetic energy harnessing. In a farm of multiple cylinders in tandem, the effect of interference on harnessing efficiency arises. Three years of systematic experiments in the Marine Renewable Laboratory (MRELab) of the University of Michigan, on an isolated cylinder, and two and three cylinders in tandem have revealed that synergistic FIO can enhance oscillations of cylinders in close proximity. Two cylinders in tandem can harness 2.5–13.5 times the hydrokinetic power of one isolated cylinder. Three cylinders in tandem can harness 3.4–26.4 times the hydrokinetic power of one isolated cylinder. Negative impact on the harnessed energy by multiple cylinders, such as the shielding effect for the downstream cylinder/s, is possible. Specifically for the three-cylinder configuration, at a certain flow speed, the decrease in the power of the middle cylinder can be overcome by adjusting its stiffness and/or damping.
Scattering of Lamb Waves Near Lamé Point at an Opening Crack
Authors: Cao Xuwei , Zeng Liang , Lin Jing 
Published: October 2020

Abstract
The scattered fields of Lamb waves resulting from damage have been extensively studied because they carry rich structural information that allow us to identify and evaluate damage. This paper investigates the interaction of the fundamental symmetric Lamb mode (S0) near the first Lamé point with opening cracks of various heights under the plane strain condition. The scattering coefficients obtained by the semi-analytical method indicate a significant non-mode-conversion point, where the mode conversion is very weak. The frequency of this non-mode-conversion point originates in the first Lamé point and increases linearly with the crack height when the normalized height is less than 25%. The finite element simulations validate the calculation results. In addition, similar phenomena are also observed for the scattering at a symmetric internal crack. These interesting scattering characteristics are related to the special mode shapes near the Lamé point, which may provide a candidate to evaluate the height of an opening crack.
Comparing video consultation and telephone consultation at the outpatient clinic of a tertiary referral centre: patient and provider benefits
Authors: Barsom Esther Z , van Dalen Anne Sophie H M , Blussé van Oud-Alblas Marjolein , Buskens Christianne J , van de Ven Anthony W H , Tanis Pieter J , Schijven Marlies P , Bemelman Willem A 
Published: October 2020

Objectives
Telephone consultations are frequently used in the outpatient setting in order to avoid unnecessary travel and to reduce hospital visit-related costs for patients. However, they are limited by the absence of non-verbal communication in contrast to video consultation. Little is known considering the possible advantages of using video consultation in comparison to telephone consultation according to both patients and healthcare providers.

Methods
Patients with colorectal diseases were asked to choose between a telephone consultation or a video consultation for their next appointment at the outpatient clinic of a tertiary referral centre. Willingness to use video consultation, value of non-verbal communication, patient satisfaction, provider satisfaction and user friendliness of the video connection technology were measured using questionnaires.

Results
None of the included patients ever had a video consultation before with a healthcare provider. Nonetheless, 22/50 preferred a video consultation over a telephone consultation. Patients who preferred a video consultation underlined the benefits of providing visual feedback to both patients and healthcare providers. Moreover, healthcare providers felt they were better able to assess the patients’ healthcare condition.

Conclusion
For patients who value both verbal and non-verbal interaction and feel comfortable with the use of video consultation, video consultation is the preferred contact modality. Shared decision making should be used to choose the preferred interaction modality. For patients with low digital skills, support might be needed or video consultation may not be the preferred choice.
Discovering themes in medical records of patients with psychogenic non-epileptic seizures
Authors: Lay Joshua , Seneviratne Udaya , Fok Anthony , Roberts Helene , Phan Thanh 
Published: October 2020

IntroductionEpileptic and psychogenic non-epileptic seizures (PNES) are common diagnostic problems encountered in hospital practice. This study explores the use of unsupervised machine learning in discovering themes in medical records of patients presenting with PNES. We hypothesised that themes generated by machine learning are comparable with the classification by human experts.MethodsThis is a retrospective analysis of the medical records in the emergency department of patients (age >18 years) with PNES who underwent inpatient video-electroencephalography monitoring from May 2009 to June 2014 and received a final diagnosis of PNES. Prior to machine learning of written text, we applied a standardised approach in natural language processing to create a document-term matrix (removal of numbers, stop-words and punctuations, transforming fonts to lower case). The words were separated into tokens and treated as if existing within a bag-of-words. A probability of each word existing within a topic (theme) was modelled on multivariate Dirichlet distribution (R Foundation, V.3.5.0). Next, we asked four experts to independently provide a clinical interpretation of the generated topics. When the majority of (≥3) experts agreed, it was regarded as highly congruent. Interactive data are available on the web at (https://gntem2.github.io/PNES/%23topic=1&lambda=0.6&term=).ResultsThere were 39 patients (74.4% women, median age 35 years with range 20–82). A total of 121 documents were converted to text files for text mining. There were 15 generated topics with 12/15 topics rated as highly congruent. The main themes were about descriptors of seizures and medication use.ConclusionsThe findings from machine learning on PNES-related documentation provides evidence for the feasibility of applying machine-learning methodology to analyse large volumes of medical records. The topics generated by machine learning were congruent with interpretations by clinicians indicating this method can be used for screening of medical conditions among large volumes of medical records.
How does self-perceived nutrition competence change over time during medical training? A prospective longitudinal observational study of New Zealand medical students
Authors: Crowley Jennifer , Ball Lauren , Wall Clare 
Published: October 2020

ObjectivesMedical nutrition education aims to equip doctors with nutrition knowledge, skills, attitudes and confidence to counsel patients to improve their diet. This study aimed to describe changes in medical students’ self-perceived nutrition competence at three time points during medical training.DesignProspective longitudinal observational study.SettingThe University of Auckland, School of Medicine.ParticipantsYear 2 medical students (phase 1, preclinical) were surveyed in May 2016. Participants repeated the survey in February 2018 as Year 4 students and July 2019 (phase 2, clinical) as Year 5 students.Primary outcome measurePrimary outcome measure was self-perceived nutrition competence measured using the validated NUTrition Competence (NUTCOMP) survey.ResultsIn 2016, 102 of 279 eligible Year 2 medical students completed the survey (response rate (RR 36.7%)). In 2018, 89 Year 4 students repeated the survey (RR 87.3%) and 30 students as Year 5 students in 2019 (RR 29.41%). There was a significant increase in total NUTCOMP scores (knowledge, skills, confidence to counsel and attitude towards nutrition) between Year 2 and Year 4 (p=0.012). There was a significant increase in the confidence to counsel construct (mean difference 7.615, 95% CI 2.291 to 12.939, p=0.003) between Year 2 and Year 4. Constructs with lowest scores at all time points were nutrition knowledge and nutrition skills. There was clear desire for more nutrition education from all students: Year 2 (mean=3.8 out of 5 (1.1)), Year 4 (mean=3.9 out of 5 (0.9)), Year 5 (mean=3.8 out of 5 (0.8)).ConclusionMedical students’ self-perceived nutrition competence in providing nutrition care increased modestly at three points throughout medical training. There remains opportunity for further supporting medical students to increase their competence in nutrition care, which could be achieved through mandatory and greater medical nutrition education.
Factors influencing use of essential surgical services in North-East India: a cross-sectional study of obstetric and gynaecological surgery
Authors: Ensor Tim , Virk Amrit , Aruparayil Noel 
Published: October 2020

IntroductionThere continues to be a large gap between need and actual use of surgery in low-resource settings. While policy frequently focuses on expanding the supply of services, demand-side factors are at least as important in determining under utilisation and over utilisation. The aim of this study is to understand how these factors influence the use of selected essential obstetric and gynaecological surgical procedures in the underserved and remote setting of North-East India.MethodsThe study combines and makes use of data from a variety of surveys and routine systems. Descriptive analysis of variations in caesarean section, hysterectomy and sterilisation and then multivariate logit analysis of demand-side and supply-side factors on access to these services is undertaken.ResultsSurgical rates vary substantially both across and within North-East India, correlated with service capacity and socioeconomic status. Travel times to surgical facilities are associated with rates of caesarean section and hysterectomy but not sterilisation where services are much more deconcentrated. Travel is less important for surgery in private facilities where capacity is much more dispersed but dominated by the non-poor. The presence of non-doctor medical staff is associated with lower levels of surgical activity.ConclusionIn low resource, remote settings policy interventions to improve access to services must recognise that surgical rates in low-resource settings are heavily influenced by demand-side factors. As well as boosting services, mechanisms need to mitigate demand-side barriers particularly distance and influence practice to encourage surgical intervention only where clinically indicated.
Family medicine residency training in Ghana after 20 years: resident attitudes about their education
Authors: Toma Ghazwan , Essuman Akye , Fetters Michael D 
Published: October 2020

ObjectiveIn addition to assessing educational needs of family medicine trainees in Ghana, we sought to assess whether those entering the training programme aimed to pursue an academic career.DesignA case study using an anonymous cross-sectional survey through collaboration between faculty members from the family medicine departments of Ghana and the University of Michigan.SettingThe family medicine postgraduate trainees and the most recent graduates in the three training sites, Accra, Kumasi and Mampong, as well as modular residents in Ghana served as the targeted participants during data collection between October and November of 2018.ParticipantsSecond and third year family medicine residents, fellows (known as senior residents in Ghana) and recent graduates were invited to participate in this study. Thirty-five of 77 eligible subjects provided responses (46% response rate), but five records were eliminated due to incomplete data to yield a survey completion rate of 39% (30/77).ResultParticipants were mostly men (n=19), and the average age of respondents was 37 years old. The participants indicated the residency programmes needed more faculty 97% (n=29), supervision during outpatient care 87% (n=26) and lectures 83% (n=25). The main reason provided by respondents for entering residency programme in family medicine, which is currently not required for practising primary care in Ghana, was to obtain more education 93% (n=28). Participants who had completed the residency programme were much more likely to be interested in becoming faculty compared with those still in residency (p <0.001).ConclusionThe research confirms the need for more faculty and the importance of investing in faculty development resources for ensuring a robust programme. These findings provide constructive feedback that could improve residency curricula of the local and regional family medicine training programmes and supports investing in trainees and new graduates as future faculty candidates.
Blood-based extracellular matrix biomarkers are correlated with clinical outcome after PD-1 inhibition in patients with metastatic melanoma
Authors: Hurkmans Daan P , Jensen Christina , Koolen Stijn L W , Aerts Joachim , Karsdal Morten Asser , Mathijssen Ron H J , Willumsen Nicholas 
Published: October 2020

BackgroundImmune checkpoint inhibitors that target the programmed cell death protein 1 (PD-1) receptor induce a response in only a subgroup of patients with metastatic melanoma. Previous research suggests that transforming growth factor beta signaling and a collagen-rich peritumoral stroma (tumor fibrosis), may negatively interfere with the interaction between T cells and tumor cells and thereby contribute to resistance mechanisms by immune-exclusion, while increased tumor infiltration of M1-like macrophages enhances T cell activity. Hence, the current study aimed to assess the relationship between blood-based markers of collagen or vimentin turnover (reflecting M1 macrophage activity) and clinical outcome in patients with metastatic melanoma after PD-1 inhibition.MethodsPatients with metastatic melanoma who were treated with anti-PD-1 monotherapy between May 2016 and March 2019 were included in a prospective observational study. N-terminal pro-peptide of type III collagen (PRO-C3) cross-linked N-terminal pro-peptides of type III collagen (PC3X), matrix metalloprotease (MMP)-degraded type III (C3M) and type IV collagen (C4M), granzyme B-degraded type IV collagen and citrullinated and MMP-degraded vimentin (VICM) were measured with immunoassays in serum before (n=107), and 6 weeks after the first administration of immunotherapy (n=94). The association between biomarker levels and overall survival (OS) or progression-free survival (PFS) was assessed.ResultsMultivariate Cox regression analysis identified high baseline PRO-C3 (Q4) and PC3X (Q4) as independent variables of worse PFS (PRO-C3: HR=1.81, 95% CI=1.06 to 3.10, p=0.030 and PC3X: HR=1.86, 95% CI=1.09 to 3.18, p=0.023). High baseline PRO-C3 was also independently related to worse OS (HR=2.08, 95% CI=1.06 to 4.09, p=0.035), whereas a high C3M/PRO-C3 ratio was related to improved OS (HR=0.42, 95% CI=0.20 to 0.90, p=0.025). An increase in VICM (p<0.0001; in 56% of the patients) was observed after 6 weeks of treatment, and an increase in VICM was independently associated with improved OS (HR=0.28, 95% CI=0.10 to 0.77, p=0.014).ConclusionsBlood-based biomarkers reflecting excessive type III collagen turnover were associated with worse OS and PFS after PD-1 inhibition in metastatic melanoma. Moreover, an increase in VICM levels after 6 weeks of treatment was associated with improved OS. These findings suggest that type III collagen and vimentin turnover contribute to resistance/response mechanisms of PD-1 inhibitors and hold promise of assessing extracellular matrix-derived and stroma-derived components to predict immunotherapy response.
Implementation of computer simulation to assess flow diversion treatment outcomes: systematic review and meta-analysis
Authors: Zhang Mingzi , Tupin Simon , Anzai Hitomi , Kohata Yutaro , Shojima Masaaki , Suzuki Kosuke , Okamoto Yoshihiro , Tanaka Katsuhiro , Yagi Takanobu , Fujimura Soichiro , Ohta Makoto 
Published: October 2020

IntroductionDespite a decade of research into virtual stent deployment and the post-stenting aneurysmal hemodynamics, the hemodynamic factors which correlate with successful treatment remain inconclusive. We aimed to examine the differences in various post-treatment hemodynamic parameters between successfully and unsuccessfully treated cases, and to quantify the additional flow diversion achievable through stent compaction or insertion of a second stent.MethodsA systematic review and meta-analysis were performed on eligible studies published from 2000 to 2019. We first classified cases according to treatment success (aneurysm occlusion) and then calculated the pooled standardized mean differences (SMD) of each available parameter to examine their association with clinical outcomes. Any additional flow diversion arising from the two common strategies for improving the stent wire density was quantified by pooling the results of such studies.ResultsWe found that differences in the aneurysmal inflow rate (SMD −6.05, 95% CI −10.87 to −1.23, p=0.01) and energy loss (SMD −5.28, 95% CI −7.09 to −3.46, p<0.001) between the successfully and unsuccessfully treated groups were indicative of statistical significance, in contrast to wall shear stress (p=0.37), intra-aneurysmal average velocity (p=0.09), vortex core-line length (p=0.46), and shear rate (p=0.09). Compacting a single stent could achieve additional flow diversion comparable to that by dual-stent implantation.ConclusionsInflow rate and energy loss have shown promise as identifiers to discriminate between successful and unsuccessful treatment, pending future research into their diagnostic performance to establish optimal cut-off values.
Cyclic thermomechanical response of fine-grained soil−concrete interface for energy piles applications
Authors: Ravera Elena , Sutman Melis , Laloui Lyesse 
Published: October 2020

Understanding the behaviour of soil−structure interfaces is critical for addressing the analysis and design of energy geostructures. In this study, the interface failure mechanism of energy piles (where a shear band is detached from the surrounding soil that behaves under oedometric conditions) is experimentally analysed in the laboratory for saturated conditions. The choice of material (clayey soil and concrete), temperature range, and stress level is based on conditions that are likely to be encountered in practice. Specifically, cyclic thermal tests under constant vertical effective stress in oedometric conditions as well as constant normal stiffness (CNS) interface direct shear tests (in which samples have been subjected to thermal cycles between 10 and 40 °C) are presented. From a practical perspective, the results show very low volumetric strain variations and negligible effects on shear strength. The volumetric aspects do not appear to have significant impact on the shear resistance of the interfaces against cyclic thermal loads. Fundamental insight on the effects of thermal cycles on the concrete−soil interface behaviour that are relevant to energy piles are presented. In addition, the proposed interpretation procedure provides a basis for the standardization of thermomechanical testing in geotechnical engineering.
Constraints on scalar–tensor theory of gravity by solar system tests
Authors: González P. A. , Olivares Marco , Papantonopoulos Eleftherios , Vásquez Yerko 
Published: October 2020

AbstractWe study the motion of particles in the background of a scalar–tensor theory of gravity in which the scalar field is kinetically coupled to the Einstein tensor. We constrain the value of the derivative parameter z through solar system tests. By considering the perihelion precession we obtain the constraint $$\sqrt{z}/m_{\mathrm{p}} > 2.6\times 10^{12}$$

z

/

m
p

>
2.6
×

10
12

m, the gravitational redshift $$\frac{\sqrt{z}}{m_{\mathrm{p}}}>2.7\times 10^{\,10}$$

z

m
p

>
2.7
×

10

10

m, the deflection of light $$\sqrt{z}/m_{\mathrm{p}} > 1.6 \times 10^{11}$$

z

/

m
p

>
1.6
×

10
11

m, and the gravitational time delay $$\sqrt{z}/m_{\mathrm{p}} > 7.9 \times 10^{12}$$

z

/

m
p

>
7.9
×

10
12

m; thereby, our results show that it is possible to constrain the value of the z parameter in agreement with the observational tests that have been considered.