bluuebunny/crossref_metadata_2025 huggingface dataset:
Modeling of pneumatic dual reciprocating bellows pump with flexible linkage
Authors: Liang Hu , Zhi-jian Gao , Tian-yi Ge , Xiao-dong Ruan , Xin Fu
Published: July 2020

Pneumatic dual reciprocating bellows pump has been widely used in chemical transportation due to its good sealing and anticorrosion performances. Nevertheless, the large outlet pulsation limits its performances on precise transportation and control of the fluid. Although the design of employing flexible linkage between the bellows has been proposed as an effective solution for this shortcoming, the design, manufacture, and control of the pump also become much more complicated. This paper presents a mathematical model to formulate the effects of structural, geometric, and control parameters to the output pulsation of pneumatic dual reciprocating bellows pump with flexible linkage. It is a dynamic model unifying several sub-models expressing the pneumatic, hydraulic, and mechanical parts in the pump, respectively. To ensure the accuracy, some special experiments are also employed to identify some key parameters in the model that cannot be determined directly. In addition, finite difference method is employed to solve the nonlinear equations. The model is well verified by comparing its computation results with experimental data. We believe that this study is valuable for guiding the design of pneumatic dual reciprocating bellows pump and optimizing its output pulsation.
Research on balanced self-weight of horizontal link heavy duty servo cylinder
Authors: Ma Linan , Zhao Xiaodong , Yang Xiaoxing , Zhang Wenze , Wang Tao
Published: July 2020

In this article, the horizontal hinged heavy duty servo cylinder is taken as the research object. In the actual working process, while the servo hydraulic cylinder outputs the curve force, the cylinder body will also rotate with the hinge point to a certain extent. Because the position of the center of gravity is constantly changing, and the weight of the cylinder body is too large, the friction causes damage to the sealing structure and seriously affects the working efficiency of the equipment. In order to improve the sealing performance of the servo hydraulic cylinder, a corresponding study is carried out. Firstly, the working angle interval of servo cylinder is optimized to ensure that the friction is the least in this range. Based on this, a new supporting structure is proposed, in which a small hydraulic cylinder is installed at the bottom of the servo hydraulic cylinder body. By controlling the output force of the small hydraulic cylinder, the cylinder body and piston rod are aligned all the time. The servo cylinder body is flexibly processed to more realistically see the adverse effect of the friction, and the co-simulation method using MSC.ADAMS and MATLAB/Simulink verifies the new support structure to improve the sealing performance. According to the simulation results and experiment results, and combined with the deformation curve of the hydraulic cylinder, when the maximum displacement is 336 mm, the maximum rotation angle is 15.6°, the friction is the smallest, about 5801.9 N. It is known from the experiment results that after adding the new support structure, the frictional force is reduced to 1365.9 N, which reduces the friction of nearly 76.5%.
Tribological behavior of dental restorative composites in chewable tobacco environment
Authors: Suryawanshi Abhijeet S , Behera Niranjana
Published: July 2020

This study investigates the effect of smokeless tobacco on the tribological properties of two commercially used dental composite materials: Tetric N-Ceram and Z350 Dentin shade. It is to evaluate the effect of smokeless tobacco on the wear properties of two dental composite materials after some stipulated period. The wear test was conducted on pin-on-disk tribometer in the presence of artificial saliva under different loading conditions of 10, 15 and 20 N. The pins of the dental composite material were immersed in tobacco solution. The tribological behavior was studied after 2 days, 3.5 days, 6 days, 15 days and 1 month which represented the real conditions for the contact of 1 week, 2 weeks, 1 month, 2 months and 5 months, respectively, between the dental material and the tobacco solution. Under different loading conditions, Z350 Dentin material exhibited much less wear than the Tetric N-Ceram material in the presence of synthetic saliva for the specimen with or without tobacco immersion. The microstructure of the pin surface was inspected using scanning electron microscopy.
Control of quadrotor trajectory tracking with sliding mode control optimized by neural networks
Authors: Raiesdana Somayeh
Published: July 2020

Quadrotor or unmanned helicopter is a mobile robot which often flies in unknown environment to perform special missions. In navigational tasks, the robot is intended to fly autonomously toward a target position by following an optimum trajectory. For a successful navigation, controlled attitude, minimum position and velocity error and obstacles collision avoidance are often considered during trajectory tracking procedure. By considering environmental variabilities and due to the existence of noises, uncertainties and unpredictable factors, it is indispensable to steer and control moving robots using sophisticated autonomous algorithms. In this work, a nonlinear model of four-rotor helicopter is simulated. An optimized terminal sliding mode control is then designed to control trajectory tracking. In order to improve the time indices for sliding mode controller, this controller is modified with neural networks. The idea is to optimize the controller parameters through a network learning process which is based on the control process error. The proposed method is evaluated with simulated and real-world indoor navigation tasks. Trajectories that are tracked by quadrotor are generated by a simultaneous localization and mapping algorithm and refined with an optimization technique. A well-known simultaneous localization and mapping technique (a camera-based extended Kalman filter-simultaneous localization and mapping) is employed to generate maps, and a path planning algorithm (particle swarm optimization) is utilized to optimize a collision-free flight path using the probability-based maps generated by simultaneous localization and mapping. Simulations and experiment are done in unknown but structured indoor environments containing a number of obstacles. The steady state error, the reaching and settle time and the chattering effect are all quantified and assessed. The controlled experimental flight robustness and sensitivity are further verified for noises occurred on vision and data acquisition system. Results indicate suitable performance for the proposed neural network-sliding mode controller. Less error and more stability were achieved comparative to the conventional sliding mode controllers.
Experimental investigation on the effects of glass fiber hybridization on the low-velocity impact response of filament-wound carbon-based composite pipes
Authors: Farhood Naseer H , Karuppanan Saravanan , Ya Hamdan H , Sultan MTH
Published: July 2020

Recently, the incorporation of several different types of fibers into a single matrix has led to the development of superior hybrid composite properties at a cheaper cost. Fiber hybridization is one of the active strategies to toughen composites and improve impact damage resistance. However, the extraordinary high strength and stiffness of the carbon fiber as well as its lower damage tolerance make it more susceptible under the impact loading. This article mainly aims to improve impact damage resistance of carbon fiber pipes through fiber hybridization strategy with glass fibers under low-velocity impact. The composite pipes reinforced with thin internal liner of high-density polyethylene were fabricated through filament winding technology. Eight pipe configurations with different stacking sequences and fiber content ratios with a constant winding angle of [Formula: see text] were fabricated and tested under impact energies, 50 and 100 J. The damage characterization was evaluated using the optical imaging and mechanical micrograph sectioning technique. Results indicate that the hybrid configurations showed better energy absorption than reference carbon fibers specimen under 50 J impact energy. Specifically, specimens with glass fibers on the exterior side and alternative configuration of carbon–glass fibers showed better impact resistance with less damage observed. Meanwhile, the specimens with glass fiber on the exterior side suffered from extreme damage with increase in the energy absorption and maximum displacement for both fiber content ratios under 100 J of impact energy.
Qualitative Research in Entrepreneurship Studies: A State-of-Science
Authors: Javadian Golshan , Dobratz Crystal , Gupta Alka , Gupta Vishal K. , Martin Jeffrey A.
Published: July 2020

Qualitative research is becoming increasingly popular in organisational studies. There is growing consensus that qualitative research contributes positively to the diversity of academic inquiry in entrepreneurship, advancing rich and novel insights about entrepreneurial phenomena. We conduct the first large-scale synthesis of the qualitative entrepreneurship research literature. Based on a sample of 460 articles published across 45 quality journals, we offer an in-depth analysis of the state of qualitative research in entrepreneurship and unearth specific patterns in common practices of published qualitative investigations. Our analysis reveals several potentially fruitful avenues for the continued application of qualitative approaches in entrepreneurship research (e.g. entrepreneur-opportunity nexus). Suggestions on why and how to use qualitative research are provided, and recommendations are offered to guide future qualitative studies to advance better understanding of entrepreneurial phenomena.
Analysis of the interaction effects between double shaking tables and test structure
Authors: Wang Juke , Li Xiaojun , Li Fangfang , Li Na
Published: July 2020

Electrohydraulic shaking tables provide a direct means to evaluate structural performance under actual vibration conditions. The control–structure interaction is one of the most important reasons for the degradation of the control performance of the shaking table. This article establishes a series of novel analytical models to investigate the control–structure interaction effects between double shaking tables and test structure. These models are the model of shaking table, the model of control error signal, the flow requirement model of servo valve, the force requirement model of actuator, and the resonance response model of structure. Based on the analytical models of the flow requirement model of servo valve, force requirement model of actuator, and resonance response model of structure, a comprehensive simulation study is conducted under different structural conditions. The study reveals the influence trend and the influence degree of the control–structure interaction on the models. Furthermore, the applications in experiments, the suggestions for the designing of the shaking table, and the deeper explorations of the control–structure interaction are obtained.
Lived Experience and Living History: A Case Study of the Black on Campus Student Journalism Project
Authors: Williams Sherri
Published: July 2020

Journalism jobs decreased significantly in the last decade and so have training opportunities for students, including Black college students. This essay explores the national student journalism project Black on Campus, a partnership with a national magazine and a university research center, that aimed to offer Black college students an opportunity to gain journalism training and be published by a national publication. This essay details how the program filled a gap in journalism training and education for Black students and documented the experiences of Black students during high racial polarization in the nation and on college campuses.
Clinically Unsuspected Injection Drug Abuse in Hospitalized Teens Diagnosed on Pathology
Authors: DiAngelo Constance , Rossi Christopher T , Mourtzinos Nikki , Huppmann Alison R
Published: July 2020

Intravenous injection of medications intended for oral use can lead to pulmonary hypertension and death. Pathologic findings in the lung include embolization of foreign material, with the specific identification of excipients accomplished through special stains. Risk factors for this type of drug abuse include indwelling venous access and chronic medical problems. These risk factors, especially in adolescent and young adult patients, should prompt intravenous drug use as a possibility of lung disease/lesions. We describe 2 patients from a pediatric hospital with pulmonary pathology indicative of intravenous drug use, identified in autopsy and surgical pathology cases. Drug abuse was not clinically suspected in either patient until the time of pathologic exam, emphasizing a need for the pathologist to be able to recognize the associated histologic changes.
Family-Specific Gains and Losses of Protein Domains in the Legume and Grass Plant Families
Authors: Yadav Akshay , Fernández-Baca David , Cannon Steven B
Published: July 2020

Protein domains can be regarded as sections of protein sequences capable of folding independently and performing specific functions. In addition to amino-acid level changes, protein sequences can also evolve through domain shuffling events such as domain insertion, deletion, or duplication. The evolution of protein domains can be studied by tracking domain changes in a selected set of species with known phylogenetic relationships. Here, we conduct such an analysis by defining domains as “features” or “descriptors,” and considering the species (target + outgroup) as instances or data-points in a data matrix. We then look for features (domains) that are significantly different between the target species and the outgroup species. We study the domain changes in 2 large, distinct groups of plant species: legumes (Fabaceae) and grasses (Poaceae), with respect to selected outgroup species. We evaluate 4 types of domain feature matrices: domain content, domain duplication, domain abundance, and domain versatility. The 4 types of domain feature matrices attempt to capture different aspects of domain changes through which the protein sequences may evolve—that is, via gain or loss of domains, increase or decrease in the copy number of domains along the sequences, expansion or contraction of domains, or through changes in the number of adjacent domain partners. All the feature matrices were analyzed using feature selection techniques and statistical tests to select protein domains that have significant different feature values in legumes and grasses. We report the biological functions of the top selected domains from the analysis of all the feature matrices. In addition, we also perform domain-centric gene ontology (dcGO) enrichment analysis on all selected domains from all 4 feature matrices to study the gene ontology terms associated with the significantly evolving domains in legumes and grasses. Domain content analysis revealed a striking loss of protein domains from the Fanconi anemia (FA) pathway, the pathway responsible for the repair of interstrand DNA crosslinks. The abundance analysis of domains found in legumes revealed an increase in glutathione synthase enzyme, an antioxidant required from nitrogen fixation, and a decrease in xanthine oxidizing enzymes, a phenomenon confirmed by previous studies. In grasses, the abundance analysis showed increases in domains related to gene silencing which could be due to polyploidy or due to enhanced response to viral infection. We provide a docker container that can be used to perform this analysis workflow on any user-defined sets of species, available at https://cloud.docker.com/u/akshayayadav/repository/docker/akshayayadav/protein-domain-evolution-project .
Climatic influence on the risk of abdominal aortic aneurysm rupture
Authors: Mestres Gaspar , Díaz María Alejandra , Fierro Alejandro , Yugueros Xavier , Tripodi Paolo , Riambau Vincent
Published: July 2020

Our aim is to examine the effects of climatic conditions on the incidence of ruptured abdominal aortic aneurysms (rAAA) in Catalonia, Spain. We combined clinical data from the Public Health official registries in Catalonia, Spain (HD-MBDS) of all rAAA with local climatic data obtained from the closest meteorological station (69 stations, National Meteorological Service: MeteoCat) from 2008 to 2017. We analyzed the median, maximum, minimum, and variability of atmospheric pressure (hPa) and air temperature (°C), solar irradiation (MJ/m2), humidity (%), accumulated precipitation (mm), median wind, and maximum flaw direction and velocity (°, m/s), recorded on the days of events, the previous day, and mean results for 3, 7, and 30 days before, as well as seasonality. Seventy-five control days were randomly selected in a 1-year period around every rAAA day at the same meteorological station, and compared. A total of 717 days and locations with rAAA were identified, and 53,775 controls were randomly selected. For the rAAA days, there were significantly lower temperatures, lower solar global irradiation, and higher mean humidity levels in all time periods ( p < 0.001, p < 0.001, p < 0.05); higher atmospheric pressure variability during 1 week and 1 month before ( p = 0.011, p = 0.007); and they often occurred during autumn/winter (57.6%, p < 0.001). Logistic regression identified low mean temperatures on the days of ruptures and high mean humidity the week before as independent rupture predictors. In conclusion, low median temperatures the same day and high humidity during 1 week before were identified as independent predictors of rAAA occurrence. The role of climate on pathophysiologic mechanisms may require further investigation.
Perspective influences eye movements during real-life conversation: Mentalising about self versus others in autism
Authors: Barzy Mahsa , Ferguson Heather J , Williams David M
Published: July 2020

Social-communication is profoundly impaired among autistic individuals. Difficulties representing others’ mental states have been linked to modulations of gaze and speech, which have also been shown to be impaired in autism. Despite these observed impairments in ‘real-world’ communicative settings, research has mostly focused on lab-based experiments, where the language is highly structured. In a pre-registered experiment, we recorded eye movements and verbal responses while adults ( N = 50) engaged in a real-life conversation. Using a novel approach, we also manipulated the perspective that participants adopted by asking them questions that were related to the self, a familiar other, or an unfamiliar other. Results replicated previous work, showing reduced attention to socially relevant information among autistic participants (i.e. less time looking at the experimenter’s face and more time looking around the background), compared to typically developing controls. Importantly, perspective modulated social attention in both groups; talking about an unfamiliar other reduced attention to potentially distracting or resource-demanding social information and increased looks to non-social background. Social attention did not differ between self and familiar other contexts, reflecting greater shared knowledge for familiar/similar others. Autistic participants spent more time looking at the background when talking about an unfamiliar other versus themselves. Future research should investigate the developmental trajectory of this effect and the cognitive mechanisms underlying it.

Lay abstract

Previous lab-based studies suggest that autistic individuals are less attentive to social aspects of their environment. In our study, we recorded the eye movements of autistic and typically developing adults while they engaged in a real-life social interaction with a partner. Results showed that autistic adults were less likely than typically developing adults to look at the experimenter’s face, and instead were more likely to look at the background. Moreover, the perspective that was adopted in the conversation (talking about self versus others) modulated the patterns of eye movements in autistic and non-autistic adults. Overall, people spent less time looking at their conversation partner’s eyes and face and more time looking at the background, when talking about an unfamiliar other compared to when talking about themselves. This pattern was magnified among autistic adults. We conclude that allocating attention to social information during conversation is cognitively effortful, but this can be mitigated when talking about a topic that is familiar to them.
“They were having so much fun, so genuinely . . .”: K-pop fan online affect and corroborated authenticity
Authors: King-O’Riain Rebecca Chiyoko
Published: July 2020

This article examines the relationship between K-pop boybands and their fandoms in the West as mediated by digital streaming performances. It investigates the socio-emotional organization of online interaction orders in K-pop fan communities, the emotional forms of expression, and the social assessment of their authenticity. The article asks two questions. First, how is the loyalty of fans elicited through the emotional experiences of fandom online? Second, how are these emotions validated by fans as “authentic”? The article argues that the experience of “liveness” is central to the process through which fans feel emotionally close to their K-pop idols and this facilitates investment by fans in emotional interactions “in real life” with other fans. Fans also rely on “corroborated authenticity.” This corroboration of internal interactions comes from two sources: (1) the presence of related/similar content on the other digital platforms and (2) the connection of the apparently “placeless” digital platforms to a particular ethnic place, Korea.
Making sense of danmu: Coherence in massive anonymous chats on Bilibili.com
Authors: Zhang Leticia-Tian , Cassany Daniel
Published: July 2020

Although coherence has been widely studied in computer-mediated communication (CMC), insufficient attention has been paid to emergent multimodal forms. This study analyzes a popular commentary system on Chinese and Japanese video-sharing sites – known as danmu or danmaku – where anonymous comments are superimposed on and scroll across the video frame. Through content and multimodal discourse analysis, we unpack danmu-mediated communication analyzing the newest interface (on Bilibili.com), the comments, the interpersonal interactions and the unusual use of the second-person pronoun. Results show that despite the technological constraints (hidden authorship, unmarked sending date and lack of options to structure comments), users construct order in interactions through repetition, danmu-specific expressions and multimodal references, while using playful language to make fun. This study provides an up-to-date analysis on an increasingly popular CMC medium beyond well-studied social networking sites, and broadens the understanding of coherence in contemporary CMC.
Disease Salience Effects on Desire for Affiliation With In-Group and Out-Group Members: Cognitive and Affective Mediators
Authors: Millar Murray , Fink-Armold Andrea , Lovitt Aileen
Published: July 2020

This study tested the hypothesis that threats related to infectious diseases would make persons less willing to affiliate with out-groups and that feelings of disgust and beliefs about the out-group members would mediate this effect. To test this hypothesis, American participants of European descent were presented with either a disease threat or control threat. Then they were shown a photograph of someone of the same race or different race. Participants were asked to indicate whether they would avoid the target person and to state their emotional and cognitive responses to the person. As predicted, disease salience decreased the desire to affiliate with out-group members, and both feelings of disgust and beliefs about the infection risk posed by the target person mediated this relationship.
Let’s Talk About Sexism: The Differential Effects of Gender Discrimination on Liberal and Conservative Women’s Political Engagement
Authors: Bankert Alexa
Published: July 2020

As the 2016 election season and the Me Too movement have powerfully demonstrated, sexism is a pervasive force not just in American politics but also, more generally, in women’s everyday lives. While political scientists have focused on the impact of sexism on voters’ evaluations of female candidates and their electoral chances, we know little about the effect of personally experienced sexism on American women’s political engagement. This manuscript tries to address this gap. Using data from the 2016 ANES Pilot Study as well as a survey experiment, I demonstrate that women who have experienced gender discrimination report higher levels of political participation and a higher chance of voting in the general election. However, among conservative women, personal experience with sexism is not associated with this participatory impetus. These findings have implications for the equal representation of women from both ends of the ideological spectrum.
The role of extracellular matrix in normal and pathological pregnancy: Future applications of microphysiological systems in reproductive medicine
Authors: O’Connor Blakely B , Pope Benjamin D , Peters Michael M , Ris-Stalpers Carrie , Parker Kevin K
Published: July 2020

Remodeling of extracellular matrix in the womb facilitates the dramatic morphogenesis of maternal and placental tissues necessary to support fetal development. In addition to providing a scaffold to support tissue structure, extracellular matrix influences pregnancy outcomes by facilitating communication between cells and their microenvironment to regulate cellular adhesion, migration, and invasion. By reviewing the functions of extracellular matrix during key developmental milestones, including fertilization, embryo implantation, placental invasion, uterine growth, and labor, we illustrate the importance of extracellular matrix during healthy pregnancy and development. We also discuss how maladaptive matrix expression contributes to infertility and obstetric diseases such as implantation failure, preeclampsia, placenta accreta, and preterm birth. Recently, advances in engineering the biotic–abiotic interface have potentiated the development of microphysiological systems, known as organs-on-chips, to represent human physiological and pathophysiological conditions in vitro. These technologies may offer new opportunities to study human fertility and provide a more granular understanding of the role of adaptive and maladaptive remodeling of the extracellular matrix during pregnancy.

Impact statement

Extracellular matrix in the womb regulates the initiation, progression, and completion of a healthy pregnancy. The composition and physical properties of extracellular matrix in the uterus and at the maternal–fetal interface are remodeled at each gestational stage, while maladaptive matrix remodeling results in obstetric disease. As in vitro models of uterine and placental tissues, including micro-and milli-scale versions of these organs on chips, are developed to overcome the inherent limitations of studying human development in vivo, we can isolate the influence of cellular and extracellular components in healthy and pathological pregnancies. By understanding and recreating key aspects of the extracellular microenvironment at the maternal–fetal interface, we can engineer microphysiological systems to improve assisted reproduction, obstetric disease treatment, and prenatal drug safety.
Association Between Body Mass Index and Perioperative Mortality After Repair of Ruptured Abdominal Aortic Aneurysms
Authors: Liang Tiffany W. , Wang S. Keisin , Dimusto Paul D. , McAninch Christopher M. , Acher Charles W. , Timsina Lava R. , Dalsing Michael C. , Motaganahalli Raghu L.
Published: July 2020

Objective:

The attempt to repair a ruptured abdominal aortic aneurysm carries a significant risk of perioperative mortality. The relationship between body mass index (BMI) and outcomes after repair of ruptured abdominal aortic aneurysms (AAAs) has not been well defined. We report the association of BMI with outcomes after ruptured AAA repair.

Methods:

Patients undergoing ruptured AAA repairs between 2008 and 2017 at 2 tertiary academic centers were included in this retrospective study. Demographics (including BMI), type of repair, length of stay, and admission mortality risk scores were gathered and analyzed using bivariate and multivariate logistic regressions. Adjusted odds ratio (AOR) was reported with 95% CIs and P values from the multivariate analysis. The primary outcome was 30-day mortality. Akaike information criterion (AIC) and c-statistics were used to assess the predictive power of models including physiologic score with or without BMI.

Results:

A total of 202 patients underwent repair of ruptured AAA. In bivariate relationship, increased BMI was significantly associated with 30-day mortality. With multivariate analysis, adjusting for demographics, type of procedure, and physiologic score, for each kg/m2 increase in BMI, an 8% increase in the likelihood of perioperative mortality (AOR = 1.08, 95% CI: 1.01-1.17; P = .04) was observed.

Conclusion:

When adjusted for admission risk score, type of procedure, and demographics, obesity was associated with increased 30-day mortality. With BMI as an additional data point, the c-statistics and AIC comparisons indicated that we would have a greater ability to preoperatively estimate mortality after ruptured AAA repair. Consideration could be made to include BMI in future mortality risk scoring systems for ruptured AAA.
Physician-Modified Endovascular Gore Excluder Graft (Handmade Modified) for Complex Abdominal Aortic Aneurysm: A Step-by-Step Approach
Authors: Lopez-Pena Gabriel , Garcia-Alva Ramon , Laparra-Escareno Hugo , Anaya-Ayala Javier E. , Guerrero-Hernández Manuel , Hinojosa Carlos A.
Published: July 2020

Endovascular repair has become the gold standard for the treatment of infrarenal abdominal aortic aneurysmal disease. Branched and fenestrated commercially custom-made devices have been developed as a treatment option for short necks or juxtarenal aneurysms. However, the lack of availability in some countries and centers, manufacturing time (6-8 weeks requirements), urgent setting in ruptured abdominal aortic aneurysms, and elevated costs make them not a widespread option. Hereby, we expose our step-by-step technique of physician modified Gore Excluder  to treat complex aneurysms. Physician-modified endovascular graft (PMEG) has emerged as an alternative to open repair for the treatment of complex aortic aneurysms. The ultimate goal of fenestrations is to increase the proximal sealing zone length. The Gore C3 delivery system allows repositioning of the graft by constraining the proximal part after a back-table physician modification; the PMEG technique with the Gore Excluder C3 delivery system can be used for complex aortic aneurysms repair as an alternative treatment option.
Investigating Assessment as Learning in Second Language Writing: A Qualitative Research Perspective
Authors: Lam Ricky
Published: July 2020

Using assessment to improve learning has become a global phenomenon. Research has shown that applying assessment for learning (AfL) in classroom contexts could increase learning gains. Despite this, not much is done to substantiate how assessment as learning (AaL), a subset of AfL, has developed to support English-as-a-second-language (ESL) pupils’ learning of writing because teacher-centered pedagogy remains prevalent in the ESL educational landscape. In this article, I first introduce the idea of AaL. Second, I review five AaL studies with a focus on what research methods they adopted and evaluate whether these methods were applied appropriately. Third, I suggest four qualitative research methods that are suitable to track how AaL could facilitate pupils’ continued writing development. Fourth, I present a case study, exemplifying how I use three research methods to investigate young adolescents’ (Grade 7) mastery of AaL skills in a forthcoming project. This article ends with methodological implications, which enlighten scholars and teachers to investigate AaL in second language writing from a qualitative research perspective.
Operation of assistive apparatus through recognition of human behavior: Development and experimental evaluation of chair-typed assistive apparatus of nine-link mechanism with 1 degree of freedom
Authors: Jun Myoungjae , Jeong Hieyong , Ohno Yuko
Published: July 2020

Because of deterioration of strength, range of joint motion, and balance ability, most care-dependent older adults require assistance to move from a seated position to a standing position. Although many sit-to-stand assisting apparatuses consisting of a seat, power transmission mechanism, and sensors have been developed, most of movements depend several actuators as the power transmission mechanism. This study aims to develop the chair-typed apparatus of nine-link mechanism with 1 degree of freedom at first, then to prove the possibility that the apparatus can be operated through the recognition of human behavior by one sensor. Here, the nine-link mechanism is divided into two mechanisms: the five link for raising the height; the four link for rotating. The mechanical part enables two input links for two mechanisms to be driven by one linear actuator simultaneously. The measurement with the infrared sensor enables the assistive apparatus to be operated automatically while patterns from measured data help the apparatus recognize what the user want to do: one is the sit-to-stand movement; the other is the stand-to-sit movement. It is discussed that the operating method through the human behavior is helpful for most older adults who are not familiar with the operation of machine.
Stable individual differences in strategies within, but not between, visual search tasks
Authors: Clarke Alasdair DF , Irons Jessica L , James Warren , Leber Andrew B , Hunt Amelia R
Published: July 2020

A striking range of individual differences has recently been reported in three different visual search tasks. These differences in performance can be attributed to strategy, that is, the efficiency with which participants control their search to complete the task quickly and accurately. Here, we ask whether an individual’s strategy and performance in one search task is correlated with how they perform in the other two. We tested 64 observers and found that even though the test–retest reliability of the tasks was high, an observer’s performance and strategy in one task was not predictive of their behaviour in the other two. These results suggest search strategies are stable over time, but context-specific. To understand visual search, we therefore need to account not only for differences between individuals but also how individuals interact with the search task and context.
Atrial fibrillation trial to evaluate real-world procedures for their utility in helping to lower stroke events: A randomized clinical trial
Authors: Huang Wen-Yi , Lee Meng , Sung Sheng-Feng , Tang Sung-Chun , Chang Kuo-Hsuan , Huang Yung-Sung , Lee Jiann-Der , Lee Tsong-Hai , Jeng Jiann-Shing , Chung Chang-Min , Wu Yi-Ling , Hsieh Tsung-Ta , Ovbiagele Bruce
Published: July 2020

Background

Enhancing detection of unrecognized atrial fibrillation among acute ischemic stroke patients is crucial for secondary stroke prevention.

Aim

To evaluate whether the detection rate of new atrial fibrillation in acute ischemic stroke patients without known atrial fibrillation could be improved by doing serial 12-lead electrocardiograms once daily for five days, compared with conventional 24-h Holter monitoring (24-h Holter).

Methods

We conducted a randomized clinical trial to compare the detection rates of paroxysmal atrial fibrillation between serial electrocardiograms versus 24-h Holter from October 2015 to October 2018 at six hospitals. Eligible participants were acute ischemic stroke patients with aged ≥65 years, with neither atrial fibrillation history nor any presence of atrial fibrillation on baseline electrocardiogram at admission. The primary outcome was newly detected electrocardiogram in the serial electrocardiograms and 24-h Holter group.

Results

Among 826 patients, baseline characteristics were similar between both groups. In the intention-to-treat analysis, there was no statistical difference between serial electrocardiograms versus 24-Holter to detect atrial fibrillation (8.4% vs. 6.9%; adjusted odds ratio 1.17, 95% confidence interval 0.69–2.01). Stepwise multivariate logistic regression revealed age ≥80 years and history of heart failure were associated with detection of paroxysmal atrial fibrillation whereas patients with lacunar infarction had lower odds for detection of paroxysmal atrial fibrillation.

Conclusions

Serial electrocardiograms had comparable detection rate of paroxysmal atrial fibrillation compared with 24-h Holter and might be a viable alternative to 24-h Holter as a first-line approach to survey for potential paroxysmal atrial fibrillation among elderly patients with acute ischemic stroke. Clinical Trial Registration: URL https://clinicaltrials.gov/ct2/show/NCT02578979 Unique Identifiers: NCT02578979
A qualitative investigation into clinical documentation: why do clinicians document the way they do?
Authors: Rowlands Stella , Tariq Amina , Coverdale Steven , Walker Sue , Wood Maryann
Published: July 2020

Background:

Clinical documentation is a fundamental component of patient care. The transition from paper based to electronic medical records/electronic health records has highlighted a number of issues associated with documentation practices including duplication. Developing new ways to document the care provided to patients and in turn, persuading clinicians to accept a change, must be supported by evidence that a change is required. In Australia, there has been a limited number of studies exploring the clinical documentation practices and beliefs of clinicians.

Objective:

To gain an in-depth understanding of clinician documentation practices.

Method:

A qualitative design using semi-structured interviews with clinicians (allied health professionals, doctors (physicians) and nurses) working in a tertiary-level hospital in South-East Queensland, Australia.

Results:

Several themes emerged from the data: environmental factors, including departmental policy and systemic issues, and personal factors, including verification, clinical reasoning and experience influencing documentation practices.

Conclusion:

Our study identified that the documentation practices of clinicians are complex, being driven by both environmental and systemic factors and personal factors. This in turn leads to duplication and some redundancy. The documentation burden of duplication could be reduced by changes in policy, supported by multidisciplinary documentation procedures and electronic systems aligned with clinician workflows, while retaining some flexible documentation practices. The documentation practices of individuals, when considered from the perspective of enhancing quality care, are considered legitimate and therefore will continue to form part of the health (medical) record regardless of the format.
Are U.S. Schools Closing the “Gifted Gap”? Analyzing Elementary and Middle Schools’ Gifted Participation and Representation Trends (2012–2016)
Authors: Yaluma Christopher B. , Tyner Adam
Published: July 2020

This article tests hypotheses by examining variations in the percentage of elementary and middle schools offering gifted and talented programs as well as gifted student participation and representation between 2012 and 2016. Using the Office of Civil Rights and the National Center for Educational Statistics (NCES) Common Core data, we find that between 2012 and 2016, the percentage of schools with gifted programs declined slightly. Crucially, gifted participation is increasing faster in low-poverty schools than in high-poverty schools. Furthermore, suburban schools became more likely to have gifted programs than urban, rural, or town schools. However, gifted participation by urbanicity decreased across all four locales. Using only 2016 data, we show that students who are Black and Hispanic continue to be statistically underrepresented. We conclude with a brief discussion and policy implications.
Written Corrective Feedback Strategies Employed by University English Lecturers: A Teacher Cognition Perspective
Authors: Wei Wei , Cao Yiqian (Katherine)
Published: July 2020

Examining EFL (English as a foreign language) teachers’ beliefs and cognition has become an essential area of research as teachers are seen as active decision makers. This study addresses teachers’ beliefs as specific to the strategies they employ when providing corrective feedback to students’ writing. Drawing on Ellis’s typology of written corrective feedback and Borg’s teacher cognition theory, this survey study investigated university EFL lecturers’ self-reported strategy use in the provision of feedback to students’ written compositions. A total of 254 respondents completed this survey from universities in Thailand, China, and Vietnam. The findings showed that the teachers provided different types of strategies, namely, high-demand (e.g., students’ response to feedback required), low-demand (e.g., correcting all errors), and no-demand feedback in relation to their students’ proficiency levels. Their choices of high-demand feedback strategies seemed to be associated with their pre- and in-service professional training experiences as well as contextual factors including local cultural influence and limited resources; whereas their uses of no-demand and low-demand feedback strategies seemed to be associated with their prior language learning experiences and classroom teaching practice. This study also revealed an inconsistency between teachers’ cognition about provision of feedback and their reported feedback strategy use. Pedagogical implications and directions for future research were also proposed.
Cancer immunoediting and immune dysregulation in multiple myeloma
Authors: Nakamura Kyohei , Smyth Mark J. , Martinet Ludovic
Published: July 2020

Avoiding immune destruction is a hallmark of cancer. Over the past few years, significant advances have been made in understanding immune dysfunction and immunosuppression in multiple myeloma (MM), and various immunotherapeutic approaches have delivered improved clinical responses. However, it is still challenging to completely eliminate malignant plasma cells (PCs) and achieve complete cure. The interplay between the immune system and malignant PCs is implicated throughout all stages of PC dyscrasias, including asymptomatic states called monoclonal gammopathy of undetermined significance and smoldering myeloma. Although the immune system effectively eliminates malignant PCs, or at least induces functional dormancy at early stages, malignant PCs eventually evade immune elimination, leading to progression to active MM, in which dysfunctional effector lymphocytes, tumor-educated immunosuppressive cells, and soluble mediators coordinately act as a barrier for antimyeloma immunity. An in-depth understanding of this dynamic process, called cancer immunoediting, will provide important insights into the immunopathology of PC dyscrasias and MM immunotherapy. Moreover, a growing body of evidence suggests that, together with nonhematopoietic stromal cells, bone marrow (BM) immune cells with unique functions support the survival of normal and malignant PCs in the BM niche, highlighting the diverse roles of immune cells beyond antimyeloma immunity. Together, the immune system critically acts as a rheostat that fine-tunes the balance between dormancy and disease progression in PC dyscrasias.
What makes a fang? Phylogenetic and ecological controls on tooth evolution in rear-fanged snakes
Authors: Westeen Erin P. , Durso Andrew M. , Grundler Michael C. , Rabosky Daniel L. , Davis Rabosky Alison R.
Published: July 2020

Background

Fangs are a putative key innovation that revolutionized prey capture and feeding in snakes, and – along with their associated venom phenotypes – have made snakes perhaps the most medically-significant vertebrate animals. Three snake clades are known for their forward-positioned fangs, and these clades (Elapidae, Viperidae, and Atractaspidinae) contain the majority of snakes that are traditionally considered venomous. However, many other snakes are “rear-fanged”: they possess potentially venom-delivering teeth situated at the rear end of the upper jaw. Quantification of fang phenotypes – and especially those of rear-fanged species – has proved challenging or impossible owing to the small size and relative rarity of many such snakes. Consequently, it has been difficult to understand the evolutionary history of both venom and prey-capture strategies across extant snakes. We quantified variation in the dentition of 145 colubriform (“advanced”) snake species using microCT scanning and compared dental characters with ecological data on species’ diet and prey capture method(s) to understand broader patterns in snake fang evolution.

Results

Dental traits such as maxilla length, tooth number, and fang size show strong phylogenetic signal across Colubriformes. We find extreme heterogeneity and evolutionary lability in the rear-fanged phenotype in colubrid (colubrine, dipsadine, and natricine lineages) and lamprophiid snakes, in contrast to relative uniformity in the front fanged phenotypes of other groups (vipers and, to a lesser extent, elapids). Fang size and position are correlated with venom-use in vipers, elapids, and colubrid snakes, with the latter group shifting fangs anteriorly by shortening the entire maxillary bone. We find that maxilla length and tooth number may also be correlated with the evolution of dietary specialization. Finally, an ancestral state reconstruction suggests that fang loss is a recurring phenomenon in colubrid snakes, likely accompanied by shifts in diet and prey capture mode.

Conclusions

Our study provides a framework for quantifying the complex morphologies associated with venom use in snakes. Our results suggest that fang phenotypes, and particularly the rear-fanged phenotype, in snakes are both diverse and labile, facilitating a wide range of ecological strategies and contributing to spectacular radiations of these organisms in tropical and subtropical biomes worldwide.