bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of ultrasonic pretreatment on thermo-mechanical properties of epoxy adhesive
Authors: Wang Hui , Liu Zhaoyi , Chen Yizhe , Hua Lin , Qiu Yi 
Published: June 2021

Abstract
Ultrasonic vibration can accelerate the curing of epoxy resin. Previous studies have not clarified the mechanism of ultrasonic vibration for accelerating the curing of epoxy resins. And the mechanical and thermal properties of the adhesive after ultrasonic-accelerated curing have not been clearly analyzed. In this study, the conventional thermal and ultrasonic-assisted curing processes of the bicomponent adhesive 3 M DP420 were characterized by tensile testing, thermogravimetric analysis, differential scanning calorimetry, dynamic mechanical analysis and Fourier transform infrared spectroscopy. The results show that the curing rate of the adhesive can be increased by 50% by ultrasonic pretreatment. The tensile test results show that ultrasonic pretreatment can increase the tensile strength by 30.9%. Pulsed ultrasonic treatment can keep the temperature of the adhesive stable during the pretreatment process, and does not excessively raise the temperature. The thermal analysis results show that pulsed ultrasonic treatment can accelerate the curing process without the loss of mechanical properties or thermal stability. It was observed that the glass transition temperature shifted to a higher value when the curing temperature increased. Ultrasonic vibration promotes mass transfer between the epoxy resin and curing agent and increases the collision probability between the reactants, thus increasing the reaction rate. In addition, it was found that the temperature field has a significant effect on the properties of the adhesive, and medium-temperature curing is more suitable for curing the adhesive.
Capturing practitioner perspectives on infrastructure resilience using Q-methodology
Authors: Kim Yeowon , Grimm Nancy B , Chester Mikhail V , Redman Charles L 
Published: June 2021

Abstract
In many disciplines, the resilience concept has applied to managing perturbations, challenges, or shocks in the system and designing an adaptive system. In particular, resilient infrastructure systems have been recognized as an alternative to traditional infrastructure, in which the systems are managed to be more reliable against unforeseen and unknown threats in urban areas. Perhaps owing to the malleable and multidisciplinary nature in the concept of resilience, there is no clear-cut standard that measures and characterizes infrastructure resilience nor how to implement the concept in practice for developing urban infrastructure systems. As a result, unavoidable subjective interpretation of the concept by practitioners and decision-makers occurs in the real world. We demonstrate the subjective perspectives on infrastructure resilience by asking practitioners working in governmental institutions within the metropolitan Phoenix area based on their interpretations of resilience, using Q-methodology. We asked practitioners to prioritize 19 key strategies for infrastructure resilience found in literature in three different decision contexts and recognized six discourses by analyzing the shared or discrete views of the practitioners. We conclude that, from the diverse perspectives on infrastructure resilience observed in this study, practitioners’ interpretation of resilience adds value to theoretical resilience concepts found in the literature by revealing why and how different resilience strategies are preferred and applied in practice.
A new solution to the regress of pure powers
Authors: Taylor Henry 
Published: June 2021

Abstract
I offer a new response to the regress argument against pure powers ontologies. This involves rejecting an overlooked premiss, which is that a power’s manifestation is exhaustively accounted for by the powers involved in it. Rejection of this premiss not only answers the regress argument, but also brings with it wider metaphysical consequences, including a shift away from one-category ontologies.
Intra-Caribbean Solidarities and the Language of Social Protest
Authors: Hamm-Rodríguez Molly , Medina Carmen Liliana 
Published: June 2021

Abstract
This essay explores the language of social protest in two geographic and diasporic locations in the Caribbean (Puerto Rico and the Dominican Republic) with long and ongoing histories of colonialism and imperialism. We analyze social media and digital mobilizing to examine how, in the midst of social protest, linguistic and semiotic tools indexed historicity, contemporaneity, and futurity through relational strategies that are not just textual and discursive, but also historical, social, and political. Throughout this essay, we share examples of intertextual and interdiscursive strategies that marked particular moments of protest as articulations of historical precedents, imperial and colonial presents, and alternative futures. These examples reveal how collective identities (i.e. el pueblo) are mobilized in social protest to generate counternarratives that address structures and systems rather than locate social critiques in particular individuals and political parties. In shedding light on the intra-Caribbean solidarities that emerge over time, this analysis also points to a need to examine the erasures (Gal and Irvine 2019) performed through claims to unity and collective organizing.
Plotting for change: an analytical framework to aid decisions on which lineages are candidate species in phylogenomic species discovery
Authors: Unmack Peter J , Adams Mark , Hammer Michael P , Johnson Jerald B , Gruber Bernd , Gilles André , Young Matthew , Georges Arthur 
Published: June 2021

Abstract
A recent study argued that coalescent-based models of species delimitation mostly delineate population structure, not species, and called for the validation of candidate species using biological information additional to the genetic information, such as phenotypic or ecological data. Here, we introduce a framework to interrogate genomic datasets and coalescent-based species trees for the presence of candidate species in situations where additional biological data are unavailable, unobtainable or uninformative. For de novo genomic studies of species boundaries, we propose six steps: (1) visualize genetic affinities among individuals to identify both discrete and admixed genetic groups from first principles and to hold aside individuals involved in contemporary admixture for independent consideration; (2) apply phylogenetic techniques to identify lineages; (3) assess diagnosability of those lineages as potential candidate species; (4) interpret the diagnosable lineages in a geographical context (sympatry, parapatry, allopatry); (5) assess significance of difference or trends in the context of sampling intensity; and (6) adopt a holistic approach to available evidence to inform decisions on species status in the difficult cases of allopatry. We adopt this approach to distinguish candidate species from within-species lineages for a widespread species complex of Australian freshwater fishes (Retropinna spp.). Our framework addresses two cornerstone issues in systematics that are often not discussed explicitly in genomic species discovery: diagnosability and how to determine it, and what criteria should be used to decide whether diagnosable lineages are conspecific or represent different species.
Deep Eutectic Solvent-Based Microwave-Assisted Extraction for the Chromatographic Analysis of Bioactive Flavonoids in Spirodela polyrrhiza
Authors: Hao Haitian , Lin Long , Liu Shun , Kang Yun , Wang Yaqin , Huang Jianming , Weng Weiyu 
Published: June 2021

Abstract
Deep eutectic solvents (DESs) are regarded as promising solvents to extract chemicals from plant materials. In this study, a DES-based microwave-assisted extraction (MAE) method was developed for the chromatographic analysis of four bioactive flavonoids in Spirodela polyrrhiza. Chromatographic separation was achieved on a Promosil C18-column. Prior to the HPLC analysis, the flavonoids were rapidly extracted by a DES–MAE process using choline chloride/levulinic acid (1:2, mol/mol) as the solvent. The extraction parameters were optimized using response surface methodology, and the optimal DES–MAE was fast and efficient compared with conventional solvent-based MAE and ultrasonic-assisted extraction using DES. The recoveries of optimized DES–MAE for the four flavonoids ranged from 97.80 to 103.29%. This study demonstrates that the validated DES–MAE–HPLC method is efficient, accurate and applicable to the determination of flavonoids in S. polyrrhiza.
Differences in mitral valve geometry between atrial and ventricular functional mitral regurgitation in patients with atrial fibrillation: a 3D transoesophageal echocardiography study
Authors: Uno Goki , Omori Taku , Shimada Shunsuke , Rader Florian , Siegel Robert J , Shiota Takahiro 
Published: June 2021

Abstract

Aims
This study investigated geometric differences in mitral valve apparatus between atrial functional mitral regurgitation (A-FMR) and functional mitral regurgitation (FMR) with left ventricular (LV) dysfunction in patients with atrial fibrillation (AF) using 3D transoesophageal echocardiography (TOE).

Methods and results
In total, 135 moderate or greater FMR patients with persistent AF or atrial flutter underwent 3D TOE. Fifty-six patients had A-FMR, defined as preserved LV ejection fraction (LVEF) of ≥50% and normal LV wall motion. Seventy-nine patients had ventricular FMR (V-FMR), defined as LV dysfunction (LVEF of &lt;50%) or LV wall motion abnormality. To evaluate mitral leaflet coaptation, the coapted area was calculated as follows: total leaflet area (TLA) in end-diastole − closed leaflet area in mid-systole. Although annular area (AA) did not significantly differ between the two groups, TLA was significantly smaller in A-FMR than in V-FMR (P = 0.005). TLA/AA, indicating the degree of the leaflet remodelling, was significantly smaller in A-FMR than in V-FMR (P &lt; 0.001). A-FMR had significantly smaller posterior mitral leaflet tethering height and angle measured at three anteroposterior planes (lateral, central, and medial) than V-FMR (all P &lt; 0.001). However, vena contracta width (VCW) measured on long-axis view on TOE and coapted area, which correlated with VCW (r = −0.464, P &lt; 0.001), were similar between the two groups.

Conclusion
Mitral leaflet remodelling may be less in A-FMR compared with V-FMR. However, leaflet tethering was smaller in A-FMR than in V-FMR, and this may result in a similar degree of mitral leaflet coaptation and mitral regurgitation severity.
Prevalence, management and impact of chronic obstructive pulmonary disease in atrial fibrillation: a systematic review and meta-analysis of 4,200,000 patients
Authors: Romiti Giulio Francesco , Corica Bernadette , Pipitone Eugenia , Vitolo Marco , Raparelli Valeria , Basili Stefania , Boriani Giuseppe , Harari Sergio , Lip Gregory Y H , Proietti Marco ,   the AF-COMET International Collaborative Group, Akao Masaharu , Barrett Tyler Warren , Campanini Mauro , Fauchier Laurent , Guo Yutao , Gussoni Gualberto , Jani Bhautesh D , Jenkins Cathy A , Kulić Mehmed , Mair Frances , SorianoMarcolino Milena , Naser Nabil , O'Brien Emily C , Ogawa Hishashi , Paixão Gabriela MM , Piccini Jonathan P , Ribeiro Antonio Luiz , Rodriguez-Mañero Moisãs 
Published: June 2021

Abstract

Aim
Prevalence of chronic obstructive pulmonary disease (COPD) in atrial fibrillation (AF) patients is unclear, and its association with adverse outcomes is often overlooked. Our aim was to estimate the prevalence of COPD, its impact on clinical management and outcomes in patients with AF, and the impact of beta-blockers (BBs) on outcomes in patients with COPD.

Methods and results
A systematic review and meta-analysis was conducted according to international guidelines. All studies reporting the prevalence of COPD in AF patients were included. Data on comorbidities, BBs and oral anticoagulant prescription, and outcomes (all-cause death, cardiovascular (CV) death, ischaemic stroke, major bleeding) were compared according to COPD and BB status. Among 46 studies, pooled prevalence of COPD was 13% [95% confidence intervals (CI) 10–16%, 95% prediction interval 2–47%]. COPD was associated with higher prevalence of comorbidities, higher CHA2DS2-VASc score and lower BB prescription [odds ratio (OR) 0.77, 95% CI 0.61–0.98]. COPD was associated with higher risk of all-cause death (OR 2.22, 95% CI 1.93–2.55), CV death (OR 1.84, 95% CI 1.39–2.43), and major bleeding (OR 1.45, 95% CI 1.17–1.80); no significant differences in outcomes were observed according to BB use in AF patients with COPD.

Conclusion
COPD is common in AF, being found in 13% of patients, and is associated with increased burden of comorbidities, differential management, and worse outcomes, with more than a two-fold higher risk of all-cause death and increased risk of CV death and major bleeding. Therapy with BBs does not increase the risk of adverse outcomes in patients with AF and COPD.
Longleaf Pine (Pinus palustris Mill.) Branch Pruning by Prescribed Fire
Authors: McGuire John P , Kush John S , Varner J Morgan , Lauer Dwight K , Mitchell J Ryan 
Published: June 2021

Abstract
Efforts to restore longleaf pine (Pinus palustris Mill.) in the southeastern US require substantial artificial regeneration. Once established, important questions remain about when to introduce fire. We investigated the impact of initial planting density on tree branching and how prescribed fire might interact with tree architecture and survival. A particular focus was on how prescribed fires could “prune” lower branches. Lower density plantings (897 trees ha−1) had more and larger live lower branches than higher density plantings (2,243 trees ha−1). Fire was effective in pruning lower branches regardless of season burned, but fire in the growing season was more effective at pruning. Branches up to a height of 1.5 to 2 m were killed by fire. Fire applied in August caused greater damage with more needles scorched and/or consumed and more stem char. Prescribed fire did not impact longleaf pine tree survival. In general, fire applied to longleaf pine facilitated pruning lower branches that affect long-term wood quality, an additional argument for its utility in restoration and management of these ecosystems.
How Widowhood and Gender Shape the Impact of Maternal Favoritism on Adult Children’s Psychological Well-Being
Authors: Suitor J Jill , Gilligan Megan , Kincaid Reilly , Hou Yifei , Stepniak Catherine , Peng Siyun 
Published: June 2021

Abstract

Objectives
Our goal was to extend research on within-family differences in mother–child relations in later life by focusing on 2 social structural characteristics of mothers and offspring that may play important roles in shaping the impact of maternal favoritism on adult children’s depressive symptoms—mother’s marital status and child’s gender.

Methods
Mixed-methods data were collected as part of the Within-Family Differences Study from 641 adult children nested within 273 families in which: (a) there were at least 2 living adult siblings, and (b) mothers were married or widowed.

Results
Multilevel analyses indicated that perceiving oneself as the child to whom one’s mother was most emotionally close was a strong predictor of higher depressive symptoms among daughters of widowed mothers; in contrast, perceptions of favoritism did not predict depressive symptoms among sons of either widowed or married mothers, or daughters of married mothers. Qualitative analyses revealed that daughters, but not sons, of widowed mothers tended to attribute their greater closeness with their mothers to their roles as their mothers’ “emotional caregivers,” particularly solo caregivers, during times when mothers faced negative life events that neither they nor their children could control or ameliorate.

Discussion
The quantitative and qualitative findings we present underscore how social structural positions—in this case, mother’s marital status and child’s gender—combine with social psychological processes to shape how parent–child relations affect children’s well-being in adulthood.
BIGwas: Single-command quality control and association testing for multi-cohort and biobank-scale GWAS/PheWAS data
Authors: Kässens Jan Christian , Wienbrandt Lars , Ellinghaus David 
Published: June 2021

Abstract

Background
Genome-wide association studies (GWAS) and phenome-wide association studies (PheWAS) involving 1 million GWAS samples from dozens of population-based biobanks present a considerable computational challenge and are carried out by large scientific groups under great expenditure of time and personnel. Automating these processes requires highly efficient and scalable methods and software, but so far there is no workflow solution to easily process 1 million GWAS samples.

Results
Here we present BIGwas, a portable, fully automated quality control and association testing pipeline for large-scale binary and quantitative trait GWAS data provided by biobank resources. By using Nextflow workflow and Singularity software container technology, BIGwas performs resource-efficient and reproducible analyses on a local computer or any high-performance compute (HPC) system with just 1 command, with no need to manually install a software execution environment or various software packages. For a single-command GWAS analysis with 974,818 individuals and 92 million genetic markers, BIGwas takes ∼16 days on a small HPC system with only 7 compute nodes to perform a complete GWAS QC and association analysis protocol. Our dynamic parallelization approach enables shorter runtimes for large HPCs.

Conclusions
Researchers without extensive bioinformatics knowledge and with few computer resources can use BIGwas to perform multi-cohort GWAS with 1 million GWAS samples and, if desired, use it to build their own (genome-wide) PheWAS resource. BIGwas is freely available for download from http://github.com/ikmb/gwas-qc and http://github.com/ikmb/gwas-assoc.
Measuring Trade Cost Reductions Through a New Bridge in Mozambique: Who Benefits From Transport Infrastructure?
Authors: Zant Wouter 
Published: June 2021

AbstractWe use spatial maize prices in Mozambique to measure transport cost reductions, attribute these reductions to road distance and road quality and assess to what extent producers, traders and consumers benefit. For identification we exploit a unique natural experiment, the construction of a new road bridge over the Zambezi River, which connects the north and south of Mozambique. The applied methodology allows for potentially oligopolistic traders with spatially varying mark-ups. Estimations are based on monthly maize prices, in 22 markets, for 5 years before and after the introduction of the bridge. Estimates of transport cost reductions, averaged over routes, vary from 3% to 7%, with large heterogeneity between routes, and roughly for two-third due to road distance and for one-third due to road quality. On average benefits of trade cost reductions are equally shared between traders and consumers, but for larger distances, a larger part accrues to traders. The evidence also indicates a reduction in prices in destination markets due to the bridge. Results are supported by observed transport cost data, robust for non-random bridge placement and strict source-destination rules.
Biomarkers of Recent Cannabis Use in Blood, Oral Fluid and Breath
Authors: Hubbard J A , Hoffman M A , Ellis S E , Sobolesky P M , Smith B E , Suhandynata R T , Sones E G , Sanford S K , Umlauf A , Huestis M A , Grelotti D J , Grant I , Marcotte T D , Fitzgerald R L 
Published: June 2021

Abstract
Proving driving under the influence of cannabis (DUIC) is difficult. Establishing a biomarker of recent use to supplement behavioral observations may be a useful alternative strategy. We determined whether cannabinoid concentrations in blood, oral fluid (OF) or breath could identify use within the past 3 h—likely the period of the greatest impairment. In a randomized trial, 191 frequent (≥4/week) and occasional (&lt;4/week) cannabis users smoked one cannabis (placebo [0.02%], or 5.9% or 13.4% Δ9-tetrahydrocannabinol [THC]) cigarette ad libitum. Blood, OF and breath samples were collected prior to and up to 6 h after smoking. Samples were analyzed for 10 cannabinoids in OF, 8 in blood and THC in breath. Frequent users had more residual THC in blood and were more likely to be categorized as ‘recently used’ prior to smoking; this did not occur in OF. Per se limits ranging from undetectable to 5 ng/mL THC in blood offered limited usefulness as biomarkers of recent use. Cannabinol (CBN, cutoff = 1 ng/mL) in blood offered 100% specificity but only 31.4% sensitivity, resulting in 100% positive predictive value (PPV) and 94.0% negative predictive value (NPV) at 4.3% prevalence; however, CBN may vary by cannabis chemovar. A 10 ng/mL THC cutoff in OF exhibited the overall highest performance to detect its use within 3 h (99.7% specificity, 82.4% sensitivity, 92.5% PPV and 99.2% NPV) but was still detectable in 23.2% of participants ∼4.4 h post-smoking, limiting specificity at later time points. OF THC may be a helpful indicator of recent cannabis intake, but this does not equate to impairment. Behavioral assessment of impairment is still required to determine DUIC. This study only involved cannabis inhalation, and additional research evaluating alternative routes of ingestion (i.e., oral) is needed.
On three-stage temperature dependence of elastic wave velocities for rocks
Authors: Li Nianqi , Fu Li-Yun , Yang Jian , Han Tongcheng 
Published: June 2021

Abstract
For most rocks, the typical temperature behavior of elastic wave velocities generally features a three-stage nonlinear characteristic that could be expressed by a reverse S-shape curve with two inflexion points. The mechanism regulating the slow-to-fast transition of elastic constants remains elusive. The physics of critical points seems related to the multimineral composition of rocks with differentiated thermodynamic properties. Based on laboratory experiments for several rocks with different levels of heterogeneity in compositions, we conduct theoretical and empirical simulations by nonlinear thermoelasticity methods and a S-shape model, respectively. The classical theory of linear thermoelasticity based on the Taylor expansion of strain energy functions has been widely used for crystals, but suffers from a deficiency in describing thermal-associated velocity variations for rocks as a polycrystal mixture. Current nonlinear thermoelasticity theory describes the third-order temperature dependence of velocity variations by incorporating the fourth-order elastic constants. It improves the description of temperature-induced three-stage velocity variations in rocks, but involves with some divergences around two inflexion points, especially at high temperatures. The S-shape model for empirical simulations demonstrates a more accurate depiction of thermal-associated three-stage variations of P-wave velocities. We investigate the physics of the parameters ${a_1}$ and ${b_1}$ in the S-shape model. These fitting parameters are closely related to thermophysical properties by being proportional to the specific heat and thermal conductivity of rocks. We discuss the mechanism that regulates the slow-to-fast transition in the three-stage nonlinear behavior for various rocks.