bluuebunny/crossref_metadata_2025 huggingface dataset:
Why do people perceive themselves as being downwardly or upwardly mobile?
Authors: Gugushvili Alexi
Published: June 2020

This study explores individual and contextual explanations of why some people perceive themselves as being mobile and others do not. While subjective social position in recent decades has become an important topic of sociological enquiry, only a handful of studies explicitly investigate the nature of subjective perception of intergenerational mobility. When assessing their performance in comparison to their parents, individuals are likely to consider many other aspects of their lives than the attainment of socio-economic position. For empirical analysis, I operationalise an objective indicator of intergenerational mobility, often assumed to be the central explanation of perceptions of mobility, by means of intergenerational educational trajectories. In addition to exploring individual-level explanations, I use multilevel mixed-effects Poisson regression models to test how contextual environment is associated with perceived intergenerational mobility across 35 societies in Europe, the Middle East and Central Asia. Results indicate that an objective measure of intergenerational mobility and other individual-level factors are important explanations of subjective intergenerational mobility. Further, the difference in economic development between individuals’ birth years and the year of interview is the most salient contextual factor explaining perceived intergenerational mobility, while contemporary economic development and short-term economic growth also reduce the likelihood of perceived downward mobility. The findings of this study contribute to sociological literature by highlighting the importance of contextual environment and factors beyond socio-economic characteristics for individuals’ perception of intergenerational mobility.
Labour migration and increasing inequality in Norway
Authors: Slettebak Marie H
Published: June 2020

This paper explores the contested relationship between migration and income inequality, using labour migration to Norway as a case. The enlargements of the European Union starting in 2004 were followed by an unprecedented increase in labour migration to Norway. In particular, many rural regions, previously unfamiliar with immigration, have experienced a large influx of labour migrants. In the same period, income inequality has increased. This paper uses register data on the municipality level from 2005–2016 to discuss (a) the direction of the relationship between labour migration and income inequality; (b) the degree to which labour migration affects inequality (in general and within the native population) compared to other immigrant groups; and (c) whether the effects are different in rural and urban municipalities. Findings show that labour migration from the ‘new’ European Union countries is followed by higher income inequality in Norway. No support is found for the reversed causal relationship that increasing inequality causes higher numbers of labour migrants. The effect of labour migration on overall inequality is considerable, but not as strong as the effect of refugees. However, as opposed to refugees, labour migration also affects income inequality within the native population, but this effect is only significant in rural areas.
Reconsidering Leonardo Da Vinci and a Memory of His Childhood
Authors: Gulati Rajiv , Pauley David
Published: June 2020

Previous considerations of Freud’s 1910 pathography of Leonardo da Vinci have grappled mainly with errors of fact (among them a mistranslation in the study’s signature childhood memory, widely known since the 1950s). Here a more consequential flaw is examined: Freud’s fatefully pathogenic framing of Leonardo’s homosexuality. While few present-day analysts share that perspective in its entirety, Freud’s complex and plausible reconstruction drew wide support in the literature for more than a century and has to date never been subjected to rigorous critique. A close reading of the study, exploring Freud’s perspective and that of later psychoanalysts and historians, seeks to account for the biography’s tenacious grip on the psychoanalytic imagination. In the end, it is argued, the pathography is a failed effort to grapple with an unsettling transformation unfolding around and within Freud: the emergence of the category that eventually would be called the “healthy homosexual.”
Religious Authenticity and Commitment
Authors: Meintel Deirdre
Published: June 2020

In this article I deal with two questions: how does religious authenticity present itself in the era of religious individualization? I find that those who are religiously active tend to emphasize the lived, personal and often embodied aspects of religious experience as evidence of authenticity and yet are likely to also have recourse to other types of claims to authenticity, such as tradition. I also raise the question of religious commitment; if religious authenticity is mostly conceived of in subjectivist terms, how is religious engagement possible over the long term? Here I examine several new types of groups that provide structure and community while leaving considerable space for individual religious experience.
An Exploration of LGBTQ+ Community Members’ Positive Perceptions of LGBTQ+ Culture
Authors: Parmenter Joshua G. , Galliher Renee V. , Maughan Adam D. A.
Published: June 2020

Although a large body of literature addresses sexual and gender identity development, little research has focused on definitions, conceptualization, and identification with LGBTQ+ culture. Fourteen LGBTQ+ emerging adults (age 20–25 years) with a diverse array of intersecting identities participated in semi-structured individual interviews aimed at exploring the construct of LGBTQ+ culture. Five of the 14 participants also participated in focus groups to further explore the conceptualization of LGBTQ+ culture that was identified in the individual interviews. Participants described the LGBTQ+ culture as a culture of survival, acceptance, and inclusion. Most participants reported a sense of pride and importance in identifying with the broader LGBTQ+ culture and believed it was beneficial in their identity development. A multidimensional conceptualization of LGBTQ+ identity development was proposed to understand the multiple levels of identifying as a marginalized sexual and/or gender diverse individual. We discuss implications for practice, education, and training.
The Effects of Early Care and Education Settings on the Kindergarten Outcomes of Doubly Vulnerable Children
Authors: Schochet Owen N. , Johnson Anna D. , Phillips Deborah A.
Published: June 2020

Program administrators and policy makers have placed a priority on expanding access to inclusive, center-based early care and education (ECE) for low-income children with special needs, a “doubly vulnerable” population characterized by academic and social-emotional achievement gaps at kindergarten entry. Yet, no research has documented the effects of center-based settings on doubly vulnerable children’s early development, either relative to other ECE settings (e.g., home-based care) or relative to each other (e.g., Head Start, public preK). The current study utilizes national data and estimates difference-in-differences models to assess the effects of these ECE setting comparisons on changes in doubly vulnerable children’s academic and social-emotional outcomes evident at kindergarten entry. Results suggest that center-based ECE is more beneficial than parental care for language and literacy, and more beneficial than home-based care for prosocial behaviors. There were few differences among center-based ECE types: At trend level, Head Start was linked with better approaches to learning and prosocial skills relative to public preK.
An energy-based model for the wear of unidirectional carbon fiber reinforced epoxy
Authors: Cheng B , Kortschot M
Published: June 2020

The wear resistance of unidirectional carbon fiber reinforced epoxy under severe abrasive sliding conditions was studied. It was found that unidirectional laminates tested with the fibers parallel to the sliding direction (UDp) were more wear resistant than the same laminates tested with fibers transverse to the sliding direction (UDap) under the same set of test conditions. A novel energy-based model was developed to explain the difference in the wear rates. It was found that the difference in wear rates between the two orientations was due to differences in the average volume to surface area ratio of the debris, the energy required to generate new surfaces, and a new k factor that represents the fraction of the total friction energy used for creating wear particles. Furthermore, wear volume per sliding distance was found to be linearly proportional the total frictional energy dissipation for both orientations. These findings can be used to simplify wear predictions for industrial applications.
Experimental and multiscale quantum mechanics modeling of the mechanical properties of PVC/graphene nanocomposite
Authors: Mashhadzadeh Amin Hamed , Fereidoon Abdolhossein , Ahangari Morteza Ghorbanzadeh
Published: June 2020

In current work, we developed mechanical properties of PVC (polyvinyl chloride)/graphene nanocomposite theoretically and experimentally. In our theoretical model, a multi-scale finite element model was used to predict Young’s modulus of the stated nanocomposite. The molecular structure of pristine graphene was treated using the density functional theory (DFT) method. By assuming graphene as a space-frame structure that preserves the discrete nature of graphene, they were modeled by the use of three-dimensional elastic beam elements for the Carbon-Carbon covalent bonds and point mass elements for the atoms. Then interfacial van der Waals interaction that exists between PVC and graphene was modeled using the general form of Lennard–Jones potential and simulated by a nonlinear truss rod model. The Lennard–Jones parameters and van der Waals forces were determined versus separation distance for the stated nonlinear truss rod via the DFT method. Finally, we prepared PVC/graphene samples with different weight percentages of graphene nanoplatelets experimentally using the melt-mixing procedure. Our computational modeling demonstrated that the magnitudes of Young’s modulus PVC/graphene were close to the experimentally obtained results until 1 wt% with an average difference of about 25%. Finally, we justified the obtained mechanical results by investigating the morphology of experimental samples using Transmission electron microscopy (TEM) and Scanning Electron Microscopy (SEM) images.
Lay-up optimisation of fibre–metal laminates panels for maximum impact absorption
Authors: Arhore Edore G , Yasaee Mehdi
Published: June 2020

This paper introduces a methodology utilising a ply-ply damage Finite Element models with Genetic algorithm optimisation procedure to investigate the effect of lay-up configuration on the impact absorption properties of fibre metal laminates (FMLs). The methodology was carried out in two steps. In the first step, a pseudo-2D model was used to explore the vast design space to identify potential optimised layup-configurations. In the second step, the optimised configurations were studied in full 3 D, with high fidelity simulations, verifying the results obtained from the optimisation process. The design variables used include thickness and material (including fibre orientation) of each ply. The results produced an optimised configuration consisting of a metallic ply on the impacted side followed by a cross-ply composite lay-up. The results also suggest that the first composite ply (second ply of the FML) should be about 3 times thicker than the other plies.
Democratic versus Authoritarian Coups: The Influence of External Actors on States’ Postcoup Political Trajectories
Authors: Thyne Clayton , Hitch Kendall
Published: June 2020

Once considered artifacts of history, research on coups has burgeoned recently. Most studies focus on decisions to stage coups, considering factors like individual benefits, organizational interests, and government legitimacy. Less work considers what happens following coups. This article considers the political trajectory of states following coups. We argue that external reactions to coups play important roles in whether coup leaders move toward authoritarianism or democratic governance. When supported by external democratic actors, coup leaders have an incentive to push for elections to retain external support and consolidate domestic legitimacy. When condemned, coup leaders are apt to trend toward authoritarianism to assure their survival. We test our argument by considering how international responses to coups from states and international organizations influence coup states’ political trajectories. Our findings indicate that international actors play key roles in determining democracy levels of coup-born regimes.
Gender Differences in Attitudes Toward Death Among Chinese College Students and the Implications for Death Education Courses
Authors: Wang Yuwei , Tang Siyuan , Hu Xin , Qin Chunxiang , Khoshnood Kaveh , Sun Mei
Published: June 2020

This study aims to explore the attitudes of college-age students to determine how they approach the idea of death by using a questionnaire that explores five separate dimensions of attitudes and beliefs. We received 1,206 completed surveys and found evidence of a substantial gender difference in attitudes toward death. These differences remain after adjustment for differences between males and females in other correlates of death attitudes and are not a function of gender differences in the dimensionality of the five scales used to characterize attitudes. We speculate that these differences originate in culturally defined expectations that are gender-related, as well as in substantial differences in individual family experiences of death. These speculations can take the form of testable hypotheses that should explain differences within genders as well as between genders. We believe that better education about death for college students can shape a healthier mental state among them.
Predictors of Problematic Social Media Use: Personality and Life-Position Indicators
Authors: Sheldon Pavica , Antony Mary Grace , Sykes Britney
Published: June 2020

Given the preponderance of social media in our increasingly saturated media environments, there is a need for greater understanding of how personality traits and states can influence problematic social media use. This study examines whether contextual age indicators (life satisfaction, interpersonal interaction, social activity), the fear of missing out, and the Big Five personality traits are significant predictors of Facebook, Instagram, and Snapchat addictions. A survey of 337 college students reveals that greater social activity is a positive predictor of addiction to Snapchat. Another significant finding is a positive relationship between social media addiction and the fear of missing out, which explained the most variance in addiction scores for Snapchat (16%). An inductive analysis of open-ended responses indicated strong similarities between those who claimed that they were addicted to these social media apps and those said that they were not addicted. Both groups described largely similar usage patterns and media dependency, yet several users did not self-identify as addicted to social media. These patterns indicate that more research is needed to determine how social media users differentiate between normative, heavy, and addicted usage.
Experimental and simulation study on chatter stability region of integral impeller with non-uniform allowance
Authors: Wu Yan , Wang Kaifa , Zheng Gang , Lv Boxin , He Yong
Published: June 2020

In order to accurately improve and predict chatter stability region of machining process, an optimization method of machining process with non-uniform allowance of integral impeller was proposed. The modal parameters of the workpiece process system were obtained using the finite element analysis. Based on the regenerative chatter analysis theory, a limit comparison diagram of the stability with uniform allowance and non-uniform allowance was established. The simulation results showed that the non-uniform allowance natural frequency is about 1.43 times as much as the uniform allowance natural frequency, and the machining system stiffness non-uniform allowance is twice as much as the uniform allowance, while the limit of chatter stability region is increased by 3 times. This article studied uniform allowance and non-uniform allowance of milling chatter stability with experimental method. Tool path for five-axis machining and machine tool simulation based on NX CAM were planned. The comparisons of cutting processing uniform allowance and non-uniform allowance were done, and the surface profile detection of the test part with the three-dimensional scanning was carried out. The experimental results showed that the average optimization rate for manufacturing precision of blade suction surface after optimization and pressure surface was 63.8% and 48.84%. The total experiment showed that this process optimization strategy could effectively improve the stiffness of the integral impeller blade and reduce the cutting chatter of the blade during the cutting process.
Unfamiliar rhythms and the micro-politics of late-modernity: An ethnography of global Hong Kong
Authors: Jankowski Krzysztof Z.
Published: June 2020

This article explores connection or disjuncture between everyday life and global culture. Efforts to de-essentialise or pluralise urban globalisation have focused on local negotiations of discourse or the macro effects of the world city, here rhythmanalysis is used to bridge these approaches. The analysis develops on the tension between the theoretically-based multiplicity and reflexivity of late-modernity, and the structured reality that has been documented. The global city is stratified through spatial and dispositional-embodied qualities that dramatically truncate the possibility of encountering unfamiliarity through everyday life. These stratifications lean on each other and replicate as ‘small worlds’ of co-constitutive, comfortable spaces. To explore this, Lefebvre’s rhythmanalysis is used to explicate participant accounts of going to a nightlife district in Hong Kong for the first time. For some, the district is present in daily life, contributing to a fluent connection and orthodox visitation. Meanwhile, subjects who visit under less seamless conditions reflexively feel out of place and corporally distinct. This article contributes to understanding the micro-politics of late-modernity, the very real, yet transparent, spatial and embodied barriers which truncate individual flourishing in late-modern societies.
Examining building age, rental housing and price filtering for affordability in Melbourne, Australia
Authors: Palm Matthew , Raynor Katrina Eve , Warren-Myers Georgia
Published: June 2020

Governments worldwide have responded to housing affordability challenges with supply-side solutions. Proponents of these approaches often draw on the notion of ‘filtering effects’ to argue that new supply naturally trickles down to lower-income households over time, improving affordability. This study examines the characteristics of Naturally Occurring Affordable Housing in Melbourne, Australia, analysing how dwelling age impacts rental cost. We specify a non-linear relationship between building age and rents through hedonic rent modelling, reflecting a premium for historic properties in inner Melbourne. We also conduct a cluster analysis of rental listings and measure affordability by cluster. Our results problematise the notion of filtering, finding that most contemporary affordable housing was initially built in the 1960s and 1970s as social housing or targeted at low-income households. We argue that filtering in this instance is not natural but is instead a reflection of historic government expenditure and past construction choices, or ‘filter up’.
Data-driven governance, smart urbanism and risk-class inequalities: Security and social credit in China
Authors: Curran Dean , Smart Alan
Published: June 2020

This article contributes to the politicisation of smart urbanism and data-driven governance by making visible some of the potential inequalities emerging from these transitions through a provisional risk-class analysis. To pursue this analysis, it focuses on the case of smart urbanism and its associated process of data-driven governance in China. It looks specifically at the manner in which Chinese smart urbanism, in terms of its security measures, including widespread use of facial recognition and the roll-out of social credit scoring, is affecting inequalities. This article proposes risk-class analysis as a toolbox that can pose new questions in the search for what types of potential risks and inequalities emerge from the smart urbanism and data-driven governance being rolled out in the Chinese context.
Cumulative risk and mental health in Chinese adolescents: The moderating role of psychological capital
Authors: Xiong Junmei , Hai Man , Wang Jintao , Li Ye , Jiang Guangrong
Published: June 2020

The current study examined the associations among cumulative risk, psychological capital and adolescents’ anxiety/depression and life satisfaction. Chinese adolescents ( N = 1473, grades 7 to 12, ages 12 to 18, 52.1% female) completed self-report cumulative risk, psychological capital, anxiety/depressive symptoms and life satisfaction questionnaires. Cumulative risk was associated with anxiety/depression and life satisfaction. Psychological capital demonstrated a compensatory effect on youth adjustment. Furthermore, a cost of resilience was observed in high-school students with high psychological capital, who showed compromised life satisfaction in conjunction with reduced anxiety/depression under circumstances of severe adversity. Psychological capital also buffered the impact of cumulative risk on anxiety/depressive symptoms in middle-school students; however, it did not moderate the relationship between cumulative risk and life satisfaction. Therefore, psychological capital cannot protect adolescents exposed to cumulative risk from the exacerbation of psychopathology and declining life satisfaction simultaneously, and a ‘toll’ exists as a byproduct of resilience in high-school students. Suggestions for school health practices were provided accordingly.
Modelling users’ perceptions of video information seeking, learning through added value and use of curated digital collections
Authors: Albertson Dan , Johnston Melissa P
Published: June 2020

Information seeking research has provided models of users in the search for information across many different contexts and situations. Digital content curation has emerged as a means for managing information and facilitating user learning by adding ‘value’ to digital content in different ways, enhancing the user experience. Using digital video and K–12 education as the context, this study examined factors representing video information seeking, user learning and use of curated video collections both individually and together as user-centred constructs. Two hundred and fifty-two K–12 teachers provided perceptions of their own information seeking processes and for different qualities of curated content and collections within the context of searching digital video for applied purposes. Results extracted underlying factors of these concepts and demonstrated significant relationships between them. Findings enabled the expansion of a model to incorporate both users’ perceptions of information seeking together with user-centred constructs of learning through added value content and use of curated digital collections. Practical implications of the study help establish baselines for future studies for formulating, incorporating and emphasising added value and video curation qualities based on users’ information seeking within the process.
Multimodal approach of venous recanalization in patients with a critical limb ischemia due to phlegmasia cerulea dolens: A case series of 17 patients in a single center
Authors: Mühlberger Dominic , Mumme Achim , Stücker Markus , Reich-Schupke Stefanie , Hummel Thomas
Published: June 2020

Objectives

Advanced phlegmasia cerulea dolens can be a hazardous complication of a deep vein thrombosis and rapid recanalization of the deep venous system is the most important factor.

Method

We describe the outcome of 17 patients with critical limb ischemia due to an advanced phlegmasia cerulea dolens. Venous thrombectomy was performed by a standardized operating procedure.

Results

Venous recanalization was successful in all patients. An additional fasciotomy was not necessary. There were five patients with an underlying malignancy and eight patients with a simultaneous pulmonary embolism. We had one amputation of a forefoot and one death within 30 days representing a 30-day mortality and an amputation rate of 6%.

Conclusions

Early recanalization and recovery of the venous outflow is mandatory for success. A multimodal therapeutic approach of high urgency surgical thrombectomy in combination with endovenous strategies could be a successful treatment option for advanced phlegmasia cerulea dolens.
Altered coupling of cerebral blood flow and functional connectivity strength in visual and higher order cognitive cortices in primary open angle glaucoma
Authors: Wang Qian , Qu Xiaoxia , Chen Weiwei , Wang Huaizhou , Huang Caiyun , Li Ting , Wang Ningli , Xian Junfang
Published: June 2020

Primary open-angle glaucoma (POAG) has been suggested to be a neurodegenerative disease associated with altered cerebral vascular hemodynamics and widespread disruption of neuronal activity within the visual, working memory, attention and executive networks. We hypothesized that disturbed neurovascular coupling in visual and higher order cognitive cortices exists in POAG patients and correlates with glaucoma stage and visual field defects. Through multimodal magnetic resonance imaging, we evaluated the cerebral blood flow (CBF)-functional connectivity strength (FCS) correlations of the whole gray matter and CBF/FCS ratio per voxel for all subjects. Compared with normal controls, POAG patients showed reduced global CBF-FCS coupling and altered CBF/FCS ratios, predominantly in regions in the visual cortex, salience network, default mode network, and dorsal attentional network. The CBF/FCS ratio was negatively correlated with glaucoma stage, and positively correlated with visual field defects in the lingual gyrus in POAG patients. Moreover, early brain changes were detected in early POAG. These findings indicate neurovascular coupling dysfunction might exist in the visual and higher order cognitive cortices in POAG patients and its clinical relevance. The results may contribute to the monitoring of POAG progression and provide insight into the pathophysiology of the neurodegenerative process in POAG.
Mechanisms of the negative potential associated with Leão’s spreading depolarization: A history of brain electrogenesis
Authors: Herreras Oscar , Makarova Julia
Published: June 2020

Spreading depolarization (SD) is a self-propagated wave that provokes transient disorder of numerous cell and tissue functions, and that may kill neurons in metabolically compromised tissue. We examined the mechanisms underlying the main hallmark of SD, a giant extracellular potential (ΔVo) for which multiple electromotive forces have been proposed. The end-point is that neurons and not glia, dendritic channels and not spatial currents, and increased sodium conductance rather than potassium gradients, appear to be the main actors in the generation of the negative ΔVo. Neuronal currents are established by two mechanisms, a voltage independent dendritic current, and the differential polarization along the neuron membranes. Notably, despite of a marked drop of ion gradients, these evolve significantly during SD, and yet the membrane potential remains clamped at zero no matter how much inward current is present. There may be substantial inward current or none in function of the evolving portion of the neuron dendrites with SD-activated channels. We propose that the ΔVo promotes swelling-induced dendritic damage. Understanding SD electrogenesis requires all elements relevant for membrane potential, action currents, field potentials and volume conduction to be jointly considered, and it has already encouraged the search for new targets to limit SD-related pathology.
#dadtribe: Performing Sharenting Labour to Commercialise Involved Fatherhood
Authors: Campana Mario , Van den Bossche Astrid , Miller Bryoney
Published: June 2020

This study looks at new developments in the commercial representation of fatherhood as exemplified by ‘Instadads’—a group of father influencers who use Instagram to document their family lives and foster a following that is attractive to brand sponsorship. With a netnography of 21 Instadad accounts and 10 in-depth interviews, we investigate how these influencers perform sharenting labour, which is the labour involved in commodifying and monetising the sharing of parental experiences. We posit that through this labour, father influencers contribute to early attempts at translating the new discursive territory of involved fatherhood into mainstream commercial representations. Sharenting labour has the potential to shift discourses on masculinities, lending more legitimacy to male parental caregiving activities.
Effect of Dexmedetomidine in children undergoing general anaesthesia with sevoflurane: a meta-analysis and systematic review
Authors: Tang Wen , He DongWei , Liu YuLin
Published: June 2020

Objective

The sedative effects of dexmedetomidine (Dex) are similar to natural sleep, with easy wakening following Dex administration, and Dex has minor effects on breathing, reducing emergence agitation in children. The aim of this study was to systematically evaluate the effects of Dex on recovery quality in children following general anaesthesia with sevoflurane, to aid clinical decision making.

Methods

Relevant randomized controlled trials published before August 2019 were searched and selected from databases. Two researchers independently screened the literature, extracted data, and assessed included studies for bias risk. Meta-analysis was performed using Stata 14.0 software.

Results

The study included 24 publications. Following general anaesthesia by sevoflurane, Dex was associated with reduced occurrence of emergence agitation (odds ratio [OR] 0.16, 95% confidence interval [CI] 0.11, 0.25) and nausea and vomiting (OR 0.40, 95% CI 0.24, 0.60), along with shortened eye-opening time (standardized mean difference [SMD] 0.72, 95% CI 0.41, 1.03), shortened extubation time (SMD 0.54, 95% CI 0.28, 0.81), and reduced duration of post-anaesthesia care unit (PACU) stay (SMD 0.29, 95% CI 0.08, 0.51) versus placebo.

Conclusion

Dexmedetomidine has positive effects on recovery quality in children undergoing general anaesthesia with sevoflurane.
Evaluation of LY573144 (lasmiditan) in a preclinical model of medication overuse headache
Authors: Rau Jill C , Navratilova Edita , Oyarzo Janice , Johnson Kirk W , Aurora Sheena K , Schwedt Todd J , Dodick David W , Porreca Frank
Published: June 2020

Background

Medication overuse is a significant issue that complicates the treatment of headache disorders. The most effective medications for the acute treatment of migraine all have the capacity to induce medication overuse headache (MOH). Novel acute migraine-specific treatments are being developed. However, because the mechanism(s) underlying medication overuse headache are not well understood, it is difficult to predict whether any particular acute medication will induce MOH in susceptible individuals. LY573144 (lasmiditan), a 5-HT1F receptor agonist, has recently been shown to be effective in the acute treatment of migraine in phase 3 trials. The aim of this study is to determine whether frequent administration of lasmiditan induces behaviors consistent with MOH in a pre-clinical rat model.

Methods

Sprague Dawley rats were administered six doses of lasmiditan (10 mg/kg), sumatriptan (10 mg/kg), or sterile water orally over 2 weeks and cutaneous allodynia was evaluated regularly in the periorbital and hindpaw regions using von Frey filaments. Testing continued until mechanosensitivity returned to baseline levels. Rats were then submitted to bright light stress (BLS) or nitric oxide (NO) donor administration and were again evaluated for cutaneous allodynia in the periorbital and hindpaw regions hourly for 5 hours.

Results

Both lasmiditan and sumatriptan exhibited comparable levels of drug-induced cutaneous allodynia in both the periorbital and hindpaw regions, which resolved after cessation of drug administration. Both lasmiditan and sumatriptan pre-treatment resulted in cutaneous allodynia that was evoked by either BLS or NO donor.

Conclusions

In a pre-clinical rat model of MOH, oral lasmiditan, like sumatriptan, induced acute transient cutaneous allodynia in the periorbital and hindpaw regions that after resolution could be re-evoked by putative migraine triggers. These results suggest that lasmiditan has the capacity to induce MOH through persistent latent peripheral and central sensitization mechanisms.
Osteochondritis Dissecans of the Knee: An Interrater Reliability Study of Magnetic Resonance Imaging Characteristics
Authors: Fabricant Peter D. , Milewski Matthew D. , Kostyun Regina O. , Wall Eric J. , Zbojniewicz Andrew M. ,   The Research in Osteochondritis of the Knee (ROCK) Study Group, Albright Jay C. , Bauer Kathryn L. , Carey James L. , Chambers Henry G. , Edmonds Eric W. , Ellis Henry B. , Ganley Theodore J. , Green Daniel W. , Grimm Nathan L. , Heyworth Benton E. , Kocher Mininder S. , Krych Aaron J. , Lyon Roger M. , Mayer Stephanie W. , Nepple Jeffrey J. , Nissen Carl W. , Pennock Andrew T. , Polousky John D. , Saluan Paul , Shea Kevin G. , Tompkins Marc A. , Weiss Jennifer , Clifton Willimon S. , Wilson Philip L. , Wright Rick W. , Myer Gregory D.
Published: June 2020

Background:

Imaging characteristics of osteochondritis dissecans (OCD) lesions quantified by magnetic resonance imaging (MRI) are often used to inform treatment and prognosis. However, the interrater reliability of clinician-driven MRI-based assessment of OCD lesions is not well documented.

Purpose:

To determine the interrater reliability of several historical and novel MRI-derived characteristics of OCD of the knee in children.

Study Design:

Cohort study (diagnosis); Level of evidence, 3

Methods:

A total of 42 OCD lesions were evaluated by 10 fellowship-trained orthopaedic surgeons using 31 different MRI characteristics, characterizing lesion size and location, condylar size, cartilage status, the interface between parent and progeny bone, and features of both the parent and the progeny bone. Interrater reliability was determined via intraclass correlation coefficients (ICCs) with 2-way random modeling, Fleiss kappa, or Krippendorff alpha as appropriate for each variable.

Results:

Raters were reliable when the lesion was measured in the coronal plane (ICC, 0.77). Almost perfect agreement was achieved for condylar size (ICC, 0.93), substantial agreement for physeal patency (ICC, 0.79), and moderate agreement for joint effusion (ICC, 0.56) and cartilage status (ICC, 0.50). Overall, raters showed significant variability regarding interface characteristics (ICC, 0.25), progeny (ICC range, 0.03 to 0.62), and parent bone measurements and qualities (ICC range, –0.02 to 0.65), with reliability being moderate at best for these measurements.

Conclusion:

This multicenter study determined the interrater reliability of MRI characteristics of OCD lesions in children. Although several measurements provided acceptable reliability, many MRI features of OCD that inform treatment decisions were unreliable. Further work will be needed to refine the unreliable characteristics and to assess the ability of those reliable characteristics to predict clinical lesion instability and prognosis.
Exploring Risk of Elder Abuse Revictimization: Development of a Model to Inform Community Response Interventions
Authors: Burnes David , Elman Alyssa , Feir Beatrice Marie , Rizzo Victoria , Chalfy Amy , Courtney Erin , Breckman Risa , Lachs Mark S. , Rosen Tony
Published: June 2020

A focus of community-based elder abuse response programs (EARP), such as Adult Protective Services, is to reduce the risk of revictimization among substantiated victims. While elder abuse (EA) risk factor research has predominantly focused on understanding the risk of initial EA onset among the general older adult population, understanding of revictimization risk among substantiated victims is weak. This study sought to identify conditions that perpetuate EA among substantiated victims. Data were collected from multiple sources: focus groups with multidisciplinary teams ( n = 35), multidisciplinary team case revictimization risk evaluations ( n = 10), and reviewing a random sample of case records ( n = 250) from a large EARP in New York City. Sixty-two indicators of EA revictimization risk were identified across several ecosystemic levels: individual victim or perpetrator, victim–perpetrator relationship, and surrounding family, home, community, and sociocultural contexts. Findings carry implications for EARP practices to reduce EA recurrence and the development of measures to evaluate EARP intervention.
Ageing and Alcohol: Drinking Typologies among Older Adults
Authors: Roche Ann M. , Harrison Nathan J. , Chapman Janine , Kostadinov Victoria , Woodman Richard J.
Published: June 2020

Objectives: Alcohol consumption and harms among older people are increasing. We examined different demographic characteristics and drinking patterns among an older population. Methods: Secondary analyses of nationally representative Australian data; subjects aged 50+ years ( N = 10,856). Two-step cluster analysis was performed to identify demographic groups and alcohol consumption behaviours. Results: Three groups were identified: Group 1 (older, unmarried, and lived alone): >65 years, moderate drinkers, poorest health, psychological distress, social disadvantage, smokers, illicit drug users, and more frequent previous alcohol treatment. Group 3 (older married): >65 years, good health, low psychological distress, less likely to drink at risky levels, and one in five drank daily. Group 2 (younger married): 50–64 years, mostly employed, highest proportion of risky drinkers and of 5+ standard drinks per session, and liberal drinking attitudes with most concern from others about their drinking. Discussion: These demographic typologies can inform targeted prevention efforts for an estimated 1.3 million adults older than 50 years drinking at risky levels.
Selective laser melting of stainless steel and silicon nitride fibre metal matrix composites
Authors: Behera Malaya Prasad , Dougherty Troy , Singamneni Sarat
Published: June 2020

Metal matrix composites are formed by adding certain filler particles to selected base metals to combine the good properties of both in the resulting composite and were proved to be quite promising in numerous applications. The main bottleneck lies in the processing methods, as the traditional solutions often lead to a loss of control on the dispersion of the filler material. The point-by-point consolidation mechanisms typical of additive manufacturing are proposed here as a possible means of enhancing this control over the composition of the metal matrix composites. Selective laser-melted composites with stainless steel 316L as the base metal and Si3 N4 as the filler phase are evaluated in the current study. The results clearly indicated that the dispersion of the filler particles is more controlled, as they are pushed and segregated around the solid front boundaries. The tensile strength of the composites is better than the pure 316L when laser-melted under appropriate process conditions. The surface quality is also substantially enhanced with the metal matrix composites.
Development and experimental investigation of an automatic control system for an excavator
Authors: Liu Guangjun , Yang Lei , Wu Di , Wu Gaoyang , Chen Hongyuan
Published: June 2020

Excavators are widely used at various construction sites, and they can significantly reduce difficulties during construction and improve construction efficiency. However, conventional excavators still exhibit many shortcomings. In certain construction environments that require precision, the construction accuracy cannot be guaranteed because excavators usually operate in harsh environments. Hence, they can cause potential life hazards to the drivers in certain situations. To address these issues, an excavator automatic control system is developed via retrofitting, modelling, and designing a control program for an excavator. This system can realise three working modes: manual operation, remote control operation, and automatic operation. A test prototype based on the aforementioned concept is developed and relevant experiments are performed. The results under automatic operation mode show that the automatic control system can move the excavator smoothly along the expected trajectory. The fluctuation in the operation velocity is low, and the positioning error to the target position is within 7 cm. Thus, the system can realise the desired control accuracy and satisfy other task design requirements.
An analytical and experimental investigation considering the effect of material flow velocity on tensile strength of a steel alloy joint produced by friction stir welding process
Authors: Hadi Behzad , Aalami-Aleagha ME , Feli Saeed
Published: June 2020

In this paper, the effects of linear speed, rotational speed, and tool radius of the pin and shoulder are investigated on the material flow velocity in friction stir welds. To obtain the maximum material flow velocity by an analytical method, a suggested relation is introduced for the rotational speed and tool optimum radius. The derived relation is based on the assumption of a velocity field in the stirring region. Besides, the effect of the linear speed on material flow velocity is investigated based on continuity and momentum equations. Finally, by using the experimental method and checking the mechanical properties of the welded parts obtained with different rotational speed, linear speed, and tool dimensions, the proposed analytical model is validated. The results indicate that in the friction stir welding process, the significant component effect on the stirring process is generated through the tool pin radius size. Besides, increasing the material flow velocity in the boundary layer increases the yield and ultimate strength of welds. To achieve the high-quality welds, rotational speed and other tool dimensions must be selected considering the equation extracted from the analytical method. Also, to make the maximum life for the pin and its components in friction stir welding of high melting point metals such as steel alloys, the operation is adjusted at a lower linear speed to prevent the destruction of the tool and improve the quality of the joint.
Influence of wheel polygonal wear on wheel-rail dynamic contact in a heavy-haul locomotive under traction conditions
Authors: Liang Hongqin , Liu Pengfei , Wang Tianlong , Wang Haoyu , Zhang Kailong , Cao Yunqiang , An Dong
Published: June 2020

For a heavy-haul locomotive within a wheel repairing period, wheel polygonal wear with different operating mileages is obtained by field testing. The test results show that the maximum radial runout of the wheel can increase to 0.87 mm and accompany with the typical damage of wheel tread shelling. Taking the wheel polygons as input excitation, the locomotive-track coupled dynamic model is established, which is verified by the comparisons of test and calculated wheelset vertical acceleration in time and frequency domains. The variable wheel-rail friction coefficient is introduced so as to consider the dry and wet rail conditions. The wheel-rail dynamic contact characteristics under the traction and dry-wet rail surface conditions are analysed simultaneously. It is found that the wheel polygon deteriorates the locomotive traction performance and induces the obvious wheel-rail slipping with large tangential stress, especially in wet rail condition. In dry condition, the wheel-rail could contact generally in the adhesion state. But the longitudinal creep forces fluctuate locally with some larger amplitudes closed to the adhesion force, which is mainly attributed to the excitation of serious wheel polygon. Comparing with the results of the newly repaired wheel, the maximum wheel-rail vertical force, longitudinal force, normal stress and tangential stress at the end of wheel repairing period can increase by 55 kN, 28 kN, 240 MPa and 470 MPa in sequence. The wheel-rail slipping and high-stress state in traction condition should be the dominant factors contributing to the wheel damage of tread shelling.
Effect of porosity gradient in cathode gas diffusion layer of polymer electrolyte membrane fuel cells on the liquid water transport using lattice Boltzmann method
Authors: Habiballahi Mohammad , Hassanzadeh Hasan , Rahnama Mohammad , Ali Mirbozorgi Seyed , Jahanshahi Javaran Ebrahim
Published: June 2020

In this paper, a two-dimensional model has been developed to simulate the liquid water transport in a cathode gas diffusion layer with different porosity gradients in polymer electrolyte membrane fuel cells (PEMFCs). Due to the complexity of porous media, the simulation was carried out by lattice Boltzmann method. According to dimensionless numbers that characterize liquid water transport in porous media, simulation conditions were similar to the liquid water transfer into the gas diffusion layer of PEMFC. Different gas diffusion layers were created randomly by solid circular particles with an average diameter of [Formula: see text] and the numerical code was validated by conducting several tests. The results indicated that capillary force is the main factor in liquid water transport in the gas diffusion layer, while viscous and gravitational forces do not have a significant effect. In addition to improve the water management, the gas diffusion layer should have a positive porosity gradient, i.e. the porosity increases along the thickness. Also, under the same boundary conditions and at the average porosity (0.659), the saturation distribution curves in three porous media were compared including the gas diffusion layer with porosity gradient, the gas diffusion layer with the micro-porous layer, and the gas diffusion layer with uniform porosity. The average liquid water saturation in the gas diffusion layer with the 10% porosity gradient was 20.2% lower than in the gas diffusion layer with uniform porosity and 10.5% lower than the gas diffusion layer + micro-porous layer. Furthermore, upon elevation of the porosity gradient in the gas diffusion layer, the average liquid water saturation in the gas diffusion layer decreased. Specifically, as the porosity gradient rose from 10% to 14% and 18.5%, the average liquid water saturation values decreased to 29.8% and 38.8%, respectively compared with the gas diffusion layer with uniform porosity.