bluuebunny/crossref_metadata_2025 huggingface dataset:
Stop the beat to see the rhythm: excitation-contraction uncoupling in cardiac research
Authors: Swift Luther M. , Kay Matthew W. , Ripplinger Crystal M. , Posnack Nikki Gillum
Published: October 2021

Optical mapping is an imaging technique that is extensively used in cardiovascular research, wherein parameter-sensitive fluorescent indicators are used to study the electrophysiology and excitation-contraction coupling of cardiac tissues. Despite many benefits of optical mapping, eliminating motion artifacts within the optical signals is a major challenge, as myocardial contraction interferes with the faithful acquisition of action potentials and intracellular calcium transients. As such, excitation-contraction uncoupling agents are frequently used to reduce signal distortion by suppressing contraction. When compared with other uncoupling agents, blebbistatin is the most frequently used, as it offers increased potency with minimal direct effects on cardiac electrophysiology. Nevertheless, blebbistatin may exert secondary effects on electrical activity, metabolism, and coronary flow, and the incorrect administration of blebbistatin to cardiac tissue can prove detrimental, resulting in erroneous interpretation of optical mapping results. In this “Getting It Right” perspective, we briefly review the literature regarding the use of blebbistatin in cardiac optical mapping experiments, highlight potential secondary effects of blebbistatin on cardiac electrical activity and metabolic demand, and conclude with the consensus of the authors on best practices for effectively using blebbistatin in optical mapping studies of cardiac tissue.
Innate Host Defense against Klebsiella pneumoniae and the Outlook for Development of Immunotherapies
Authors: Opoku-Temeng Clement , Malachowa Natalia , Kobayashi Scott D. , DeLeo Frank R.
Published: October 2021

Klebsiella pneumoniae (K. pneumoniae) is a Gram-negative commensal bacterium and opportunistic pathogen. In healthy individuals, the innate immune system is adept at protecting against K. pneumoniae infection. Notably, the serum complement system and phagocytic leukocytes (e.g., neutrophils) are highly effective at eliminating K. pneumoniae and thereby preventing severe disease. On the other hand, the microbe is a major cause of healthcare-associated infections, especially in individuals with underlying susceptibility factors, such as pre-existing severe illness or immune suppression. The burden of K. pneumoniae infections in hospitals is compounded by antibiotic resistance. Treatment of these infections is often difficult largely because the microbes are usually resistant to multiple antibiotics (multidrug resistant [MDR]). There are a limited number of treatment options for these infections and new therapies, and preventative measures are needed. Here, we review host defense against K. pneumoniae and discuss recent therapeutic measures and vaccine approaches directed to treat and prevent severe disease caused by MDR K. pneumoniae.
Adults with Congenital Heart Disease Move Well but Lack Intensity: A Cross-Sectional Study Using Wrist-Worn Physical Activity Trackers
Authors: Brudy Leon , Häcker Anna-Luisa , Meyer Michael , Oberhoffer Renate , Hager Alfred , Ewert Peter , Müller Jan
Published: October 2021

Objective: This study compared objectively measured and self-reported physical activity (PA) in adults with congenital heart disease (ACHD) to a healthy reference cohort (RC). Patients and Methods: From May 2017 to August 2020, 211 ACHD (39.9 ± 9.7 years, 101 female) and 141 healthy adults (35.9 ± 14.7 years, 76 female) participated in a wearable-based and self-reported PA assessment. Moderate-to-vigorous PA (MVPA) and the step count were recorded with the Garmin vivofit® 3 device for 7 consecutive days. Additionally, subjects were asked to report the number of days they are active for ≥30 min throughout the week. Results: Only 33 (17%) ACHD and 36 (26%) healthy controls (p = 0.030) accumulated the World Health Organization’s (WHO) recommendation of 150 min MVPA per week. ACHD were less active per week (ACHD: 40.0 [0.0; 101.0] min. MVPA vs. RC: 75.0 [22.5; 152.5] min. MVPA, p = 0.002) and walked fewer daily steps (ACHD: 8,246 [6,505; 10,434] vs. RC: 9,413 [7,621; 11,654], p = 0.001) than healthy controls. Especially, patients with moderate (p = 0.030), complex (p < 0.001), or surgically corrected (p = 0.008) congenital heart disease accumulated significantly less MVPA than healthy peers throughout the week. A large majority of 72% of ACHD and 58% of the RC overestimated their weekly active days by more than one day. Conclusions: ACHD walked quite a few steps daily but lacked intensity. ACHD was less active than healthy controls and failed to reach international recommendations. They therefore need encouragement toward more intense movement to improve the exercise capacity and lower cardiovascular risk. Self-reported PA showed no agreement to the objectively measured PA.
Exploring the Importance of Motor Competence for Behavioral and Health Outcomes in Youth
Authors: Chagas Daniel das Virgens , Marinho Blena
Published: October 2021

In this study, we investigated the relationship between motor competence (MC) and behavioral and health outcomes in youth through its relationship to physical activity (PA) and body composition (in terms of body fat). To date, it is unclear whether these variables reciprocally influence each other over time. We assessed whether and how MC, PA and body composition influence each other across adolescence. In a longitudinal study with 14 months of follow-up, we recruited 166 adolescents aged 12–13 years. We recorded participants’ self-reported PA and body fat percentage and assessed their MC using the Körperkoordinationstest für Kinder (KTK). We used linear mixed models and mediation analyses with crude and adjusted (age, sex, time point) models to examine associations among the selected variables across time. MC showed a bidirectional relationship with both PA ( p < .001) and body fat ( p < .001) in both crude and adjusted models. In addition, MC was a potential mediator (Sobel test = –3.18, p < .001) in the relation between body fat (as predictor) and PA (as outcome) in crude models, but no mediating effect was found in adjusted models. Thus, this study provided longitudinal evidence that MC and PA, as well as MC and body composition, can reciprocally influence each other across adolescence. We recommend the development of MC as a crucial strategy to increase PA engagement and to prevent obesity in youth.
The spectral material culture in ordinary life: Re-imagining obsessive-compulsive disorder (OCD)
Authors: Parish Jane
Published: October 2021

In 2020 obsessive-compulsive disorder (OCD) was ranked by the World Health Organisation as one of the top-10 most disabling diseases. Today, it is the fourth most common mental disorder in the United Kingdom. This research is based upon ethnographic fieldwork conducted since 2016 in Merseyside and Cheshire, UK, which re-imagines obsessive thoughts and compulsive rituals among women who self-diagnosed as having ‘magical thinking OCD’. Referring to variations in the brain, OCD is often described as a type of neurodiversity. While, in popular culture, representations of OCD practices invariably invoke anthropological ideas of magical correspondence and animism as objects are assumed to possess an overpowering agency over the person who is supposed to master their possessions. This study aims to firmly place the notion of OCD in the realm of a spectral material culture and initiate a wider sociological conversation about the ‘haunting’ of a wide range of subject-objects. In doing so, I want to remove magic from the normative shadow of concepts such as the mysterious and the ghostly and instead employ the ordinary everyday as a sociological analytic for understanding the magic of mass-produced things and global processes of automation.
Fabric defect detection based on feature fusion of a convolutional neural network and optimized extreme learning machine
Authors: Zhou Zhiyu , Deng Wenxiong , Zhu Zefei , Wang Yaming , Du Jiayou , Liu Xiangqi
Published: October 2021

Aiming to accurately detect various defects in the fabric production process, we propose a fabric defect detection algorithm based on the feature fusion of a convolutional neural network (CNN) and optimized extreme learning machine (ELM). Firstly, we use transfer learning to transfer the parameters of the first 13 convolutional layers and first two fully connected layers of a VGG16 network model as pre-trained by ImageNet to the initial model and fine-tune the parameters. Subsequently, the fine-tuned model is used as a feature extractor to extract features of RGB images and their corresponding L-component images. A principal component analysis is used to reduce the dimensionality of the features and fuse the reduced features. The moth flame optimization (MFO) algorithm is used to initialize the optimization variables of a parallel chaotic search (PCS) algorithm, and the PCS algorithm (as optimized by the MFO algorithm) is used to optimize the input weight and bias of the ELM (i.e., the PCS-MFO-ELM (PMELM)). Finally, the PMELM is used to replace the softmax classifier of the CNN to classify and detect fabric defect features. The experimental results show that on the amplified TILDA dataset, the precision, recall, F1-score, and accuracy rates of this algorithm for fabric holes, stains, warp breaks, dragging, and folds in fabric can reach 98.57%, 98.52%, 98.52%, and 98.50%, respectively, that is, higher than those of other algorithms. Through a validity experiment, this method is shown to be suitable for defect detection for unpatterned fabrics, regular patterned fabrics, and irregularly patterned fabrics.
Removal of a Giant Parapharyngeal Space Oncocytoma Without Osteotomy
Authors: Matsuki Takashi , Tsutsumi Shohei , Miyamoto Shunsuke , Kano Koichi , Momiyama Kaho , Asako Yukiko , Yamashita Taku
Published: October 2021

Oncocytoma arising from the parotid gland and extending into the parapharyngeal space (PPS) has not been previously reported. A 64-year-old woman presented with a large slowly growing mass extending from the parotid to the submandibular area, expanding medially to displace the pharynx across the midline. Core-needle biopsy revealed an oncocytoma in the PPS measuring 120 × 88 × 60 mm in size. Although the tumor was of an unprecedentedly large size and extended into multiple spaces, it could be removed via a cervical–parotid approach without osteotomy. The resected tumor was again diagnosed as oncocytoma. A postoperative complication was weakness of the ipsilateral facial nerve, which almost completely resolved in 6 months. No recurrence has been noted on 1 y follow-up. We were able to resect an extremely large oncocytoma arising from the parotid gland without osteotomy.
Pandemic protests: Creatively using the freedom of assembly during COVID-19
Authors: Buyse Antoine
Published: October 2021

It is a new truism that the COVID-19 pandemic has exacerbated an already dire human rights situation across the globe. The waves of protest that swept across the world in the year before the pandemic seemed to have been brought to a sudden halt due to lockdowns and restrictive laws. But at the same time, people everywhere have availed themselves of the wide protective scope of the freedom of assembly, newly re-emphasized in the Human Rights Committee's General Comment of 2020, to come together, protest, and make their voices heard in numerous creative ways. Amid the restrictions, there has been resilience.
The role of L1 reading direction on L2 perceptual span: An eye-tracking study investigating Hindi and Urdu speakers
Authors: Fernandez Leigh B , Bothe Ricarda , Allen Shanley EM
Published: October 2021

In the current study we used the gaze-contingent moving window paradigm to directly compare the second language (L2) English perceptual span of two groups that speak languages with essentially the same lexicon and grammar but crucially with different writing directions (and scripts): Hindi (read left to right) and Urdu (read right to left). This is the first study to directly compare first language (L1) speakers of languages that differ primarily in reading direction in a common L2, English. While Urdu speakers had a slightly faster reading rate, we found no additional differences between Hindi and Urdu speakers when reading L2 English; both groups showed a perceptual span between 9 and 11 characters to the right of the fixation based on saccade length. This suggests little to no influence of L1 reading direction on L2 perceptual span, but rather that L2 perceptual span is influenced by allocation of attention during reading. Our data are in line with research by Leung et al. (2014) finding that L2 speakers have a smaller perceptual span than native speakers (L1 perceptual span is approximately 15 characters to the right of the fixation). This most likely stems from the increased demands associated with reading in a second language, which led to a reduction in the amount of attention that can be allocated outside of the current fixation.
Lower limb amputation following venous cannulation for VA-ECMO: a case report
Authors: Habr Natasha , Hoballah Jamal J , Borgi Jamil , Hamadi Caroline , Sfeir Pierre , Haddad Fady
Published: October 2021

Lower limb amputation following arterial cannulation for VA-ECMO has been described in the literature. Limb ischemia however following venous cannulation is very rare and not quite understood. We present a case of limb ischemia following venous cannulation. A combination of venous congestion, compartment syndrome and subsequent arterial insufficiency is the proposed pathophysiology. Shock and use of vasopressors are compounding factors. Limb ischemia can be transient and reversible if diagnosed immediately and treated by early removal of the cannula. Our patient was unstable and ECMO dependent, and removal of the cannula was not an option. This resulted in limb loss and eventual above knee amputation. Use of the smallest appropriate venous cannula and early fasciotomy, in addition to hemodynamic optimization are measures that could help in preventing major amputation.
Dislocations in an arbitrary angle wedge. Part II: Cracks in the wedge
Authors: Riddoch Daniel J , Cwiekala Nils , Hills David A
Published: October 2021

We describe a method for calculating the crack tip stress intensity factors for the problem of one or two cracks at the apex of an arbitrary angle wedge. The kernels for a dislocation in an arbitrary angle wedge described in part 1 of this paper are used extensively. Consideration is given to variations of crack length, crack angle and wedge angle.
Faculty Perspectives on the Recruitment, Retention, and Preparation of Special Education Doctoral Students of Color
Authors: Maggin Daniel M. , Collins Tai A. , Foster Josalyn A. , Scott Meagan N. , Mossing Kandace W. , Dorsey Catrina M.
Published: October 2021

The field of special education continues to grapple with the presence and implications of disproportional representation related to race and ethnicity. While research focuses mostly on disproportional representation of students, there remains long-standing acknowledgment that too few students of color populate our special education university doctoral programs. The present study, therefore, surveyed current special education faculty members at doctoral degree granting institutions to understand the practices used to recruit and retain doctoral students of color and perspectives on their programs’ climate related to racial and ethnic diversity. In addition, the research team conducted a series of exploratory analyses to examine whether responses depended on respondent race or whether the respondent worked at a minority-serving institution. Results suggest a general commitment to increasing doctoral student diversity; however, there appears a lack of formalized plans and culturally relevant coursework. Findings of the exploratory analyses suggest that programs within minority-serving institutions may provide important leadership in this area. We conclude with limitations and recommendations for doctoral programs.
Aero-engine acceleration control using deep reinforcement learning with phase-based reward function
Authors: Hu Qian-Kun , Zhao Yong-Ping
Published: October 2021

In this paper, the conventional aero-engine acceleration control task is formulated into a Markov Decision Process (MDP) problem. Then, a novel phase-based reward function is proposed to enhance the performance of deep reinforcement learning (DRL) in solving feedback control tasks. With that reward function, an aero-engine controller based on Trust Region Policy Optimization (TRPO) is developed to improve the aero-engine acceleration performance. Four comparison simulations were conducted to verify the effectiveness of the proposed methods. The simulation results show that the phase-based reward function helps to eliminate the oscillation problem of the aero-engine control system, which is caused by the traditional goal-based reward function when DRL is applied to the aero-engine control. And the TRPO controller outperforms deep Q-learning (DQN) and the proportional-integral-derivative (PID) in the aero-engine acceleration control task. Compared to DQN and PID controller, the acceleration time of aero-engine is decreased by 0.6 and 2.58 s, respectively, and the aero-engine acceleration performance is improved by 16.8 and 46.4 % each.
Bearing fault detection under time-varying speed based on empirical wavelet transform, cultural clan-based optimization algorithm, and random forest classifier
Authors: Imane Moussaoui , Rahmoune Chemseddine , Zair Mohamed , Benazzouz Djamel
Published: October 2021

Bearings are massively utilized in industries of nowadays due to their huge importance. Nevertheless, their defects can heavily affect the machines performance. Therefore, many researchers are working on bearing fault detection and classification; however, most of the works are carried out under constant speed conditions, while bearings usually operate under varying speed conditions making the task more challenging. In this paper, we propose a new method for bearing condition monitoring under time-varying speed that is able to detect the fault efficiently from the vibration signatures. First, the vibration signal is processed with the Empirical Wavelet Transform to extract the AM-FM modes. Next, time domain features are calculated from each mode. Then, the features’ set is reduced using the Cultural Clan-based optimization algorithm by removing the redundant and unimportant parameters that may mislead the classification. Finally, an ensemble learning algorithm “Random Forest” is used to train a model able to classify the fault based on the selected features. The proposed method was tested on a time-varying real dataset consisting of three different bearing health states: healthy, outer race defect, and inner race defect. The obtained results indicate the ability of our proposed method to handle the speed variability issue in bearing fault detection with high efficiency.
International, innovative, multimodal and representative? The geographies, methods, modes and aims present in two visual communication journals
Authors: Thomson TJ
Published: October 2021

This comparative review seeks to explore how international, innovative, multimodal and representative the scholarship published in two visual communication journals, Visual Communication ( VC) and Visual Communication Quarterly ( VCQ), is over a 25-year period (from VCQ’s founding in 1994 and from VC’s founding in 2002 through 2019). Through examining all 544 research articles published in these journals over this timeframe, an understanding can be achieved regarding which countries and geographic regions have received attention, the methods and means used to advance the authors’ arguments, the visuals under consideration and the authors’ focus and aims, which sometimes overlap with the visuals under consideration and are sometimes distinct from them. The results inform areas of potential future exploration, focus and attention for these two journals but are grounded in an understanding that systemic conditions also influence the types and designs of research that can be published and recognized.
Intrafamilial Characteristics Are Important Predictors of Children’s Diets in New Mexico’s Border Colonias
Authors: McDonald Jill A. , Sroka Christopher J. , Olivares Elizabeth , Marin Merranda R. , Gurrola Maria , Sharkey Joseph R.
Published: October 2021

Introduction

We assessed selected nutritional indicators in Mexican-origin children in two low-income, rural colonias in New Mexico on the U.S.–Mexico border. These children are at higher risk for obesity and other chronic diseases linked to poor nutrition in childhood, but little is known about their diets.

Method

We surveyed mothers of 202 children 6 to 10 years old about sociodemographic characteristics, family and child attitudes and behaviors, and the child’s diet. We compared diet with dietary recommendations and used regression trees to identify significant predictors of recommended intake.

Results

Among families, 89.1% participated in Medicaid, and 52.5% participated in a Supplemental Nutrition Program. More children met recommendations for fruit (36.1%) than vegetables (1.5%). Greater vegetable intake was associated with a child’s not thinking healthy food tasted bad, greater family activity, and younger maternal age. Only 5.0% of children met the recommendation for <10% of energy from added sugar, with the average child consuming 2.4 times that from sugar-sweetened beverages and snacks. Lower sugar intake was associated with less screen time, not having TV on during meals, and playing team sports. Family access to healthy food and child use of mobile food vendors, vending and convenience stores were not predictive of diet.

Conclusion

Hispanic children in border colonias have poor diets that put them at risk for obesity and numerous chronic diseases. Addressing this problem will require changing family norms and attitudes toward healthy food, screen time behavior, and physical activity levels within families.
Group Social Support Facilitates Adoption of Healthier Behaviors Among Black Women in a Community-Initiated National Diabetes Prevention Program
Authors: O’Neal LaToya J. , Scarton Lisa , Dhar Biswadeep
Published: October 2021

The aim of this study was to better understand facilitators and barriers of the early adoption of healthy eating and physical activity behaviors among Black women participating in a community-based, community-initiated diabetes education program. We held focus groups with participants ( N = 14) ages 24 to 90 years. Participants were recruited from a multisite, community-based diabetes prevention program in the Southeastern United States. Data were collected in March and June of 2017. Barriers and facilitators of change were categorized using the socioecological model with interpersonal, intrapersonal, community, and environmental factors serving as the foundation for thematic content. Participants reported the adoption of several behavioral changes resulting in positive health outcomes. They also identified several facilitators and few barriers to initial behavior change on participating in the diabetes prevention program. The greatest facilitator was interpersonal, while the greatest barriers were community and/or environmental. Understanding the factors that improve or impede the successful adoption of health behaviors among Black women participating in a behavioral lifestyle program will allow us to develop stronger, more tailored interventions that provide the greatest impact to assist in improving weight loss outcomes and reducing the burden of diabetes among Black women.
‘And I would ask myself, what’s being gay got to do with this anyway?’ Constructions of queer subject positions in student’s stories
Authors: Francis Dennis A
Published: October 2021

In this paper, the author explores some of the issues associated with teaching about compulsory heterosexuality and schooling in an undergraduate sociology programme. Using a novel approach to gathering data, the article analyses the stories students submitted about themselves or others who were counter normative in terms of gender and sexuality in school. Informed by the work of Ahmed and Foucault, this article explores what kinds of gendered and sexualised subject positions become possible through the stories of students, and how are these subject positions interpellated and constituted relationally? Despite progressive legislation, queer activism and the significant visibility of gender and sexuality counter-normative identities in the South African media, the analysis highlights that students’ position school attending queer youth as (1) stereotyped caricatured subjects, (2) objects of fear and (3) subjects of violence. These subject positions serve as straightening devices that interpellate queer school attending youth as unfamiliar, not belonging and unworthy and therefore requiring change. Insights from this article can inform the research and practice which is pivotal to addressing cisheteronormativity not only in schools but cultural ideas, norms and practices too.
Perceptual History Acts in World-Centred Coordinates
Authors: Mikellidou Kyriaki , Cicchini Guido Marco , Burr David C.
Published: October 2021

Serial dependence effects have been observed using a variety of stimuli and tasks, revealing that the recent past can bias current percepts, leading to increased similarity between two. The aim of this study is to determine whether this temporal integration occurs in egocentric or allocentric coordinates. We asked participants to perform an orientation reproduction task using grating stimuli while the head was kept at a fixed position, or after a 40° yaw rotation between trials, from left (−20°) to right (+20°), putting the egocentric and allocentric cues in conflict. Under these conditions, allocentric cues prevailed.
Examining National Trends of Teacher Certification in Autism: Implications for Rural Schools
Authors: Albright Jordan , Williams Thomas O.
Published: October 2021

This study examined the national trends of teacher certification in autism in an effort to better understand the characteristics of individuals who seek this credential, how these characteristics change over time, and where teachers with this certification are currently working in an effort to identify recruitment and retention strategies to areas most in need. This ex post facto study consisted of a secondary analysis of the 2011 to 2012 Schools and Staffing Survey Teacher Questionnaire and the 2015 to 2016 National Teacher and Principal Survey Teacher Questionnaire. The results suggest that the majority of licensed teachers who receive an autism certification are working in special education. In addition, while overall trends indicate an increase in the number of teachers who report an autism certification, fewer teachers with this certification are working in rural school districts. These results have important implications for school-service delivery for students with autism spectrum disorder, specifically those living and attending school in rural communities.
Using Caregiver Support to Promote Efficacy of Nontraditional Instruction Provided to Students With Extensive Support Needs
Authors: Brewer Brandy N. , Riggs Leah A. , Courtade Ginevra , Landrum Timothy J.
Published: October 2021

The COVID-19 pandemic has been one of the most dramatic and far-reaching events to impact education in recent years. At the onset of this global crisis, schools were required to pivot, with little warning or planning, to educate the more than 50 million school-age children in the United States through some form of nontraditional instruction (NTI), which often involved technology-based distance education. While shifts to NTI for short time periods may be feasible for many students, the potential impact of long-term NTI on students with extensive support needs (ESNs) and their families, especially in rural areas, may be particularly acute. In this article, we discuss specific strategies that address and incorporate what we know about extended NTI in rural school districts, including both lessons learned and areas of concern, with particular attention to the role and importance of caregivers. We outline ways that caregivers can be supported and how natural environment teaching provides one useful framework for efforts to reduce skill regression and to increase the overall potential for skill generalization when traditional schooling is interrupted.
Thomas Szasz: The uncompromising rebel and critic of psychiatry
Authors: Domaradzki Jan
Published: October 2021

Zmarły w roku 2012 profesor Thomas Szasz obchodziłby w kwietniu bieżącego roku swoje setne urodziny. W tym toku przypada również sześćdziesiąta rocznica publikacji jego obrazoburczej tezy o micie choroby psychicznej. Stąd, celem niniejszego tekstu jest charakterystyka najważniejszych poglądów Szasza na temat choroby psychicznej i współczesnej psychiatrii. Ukazując źródła poglądów amerykańskiego psychiatry zaprezentowane zostaną w szczególności jego rozważania dotyczące rozróżnienia między chorobą somatyczną i chorobą umysłową, postępującej medykalizacji życia codziennego, psychiatrii rozumianej jako instytucja kontroli społecznej, a także jego krytyka tzw. państwa terapeutycznego, a więc sojuszu psychiatrii i państwa. Nakreślone zostają także poglądy Szasza na temat swobody, wolności jednostki i osobistej odpowiedzialności. Nadto, prezentując główne zarzuty formułowane wobec Szasza przez jego krytyków tekst podejmuje próbę ukazania wpływu koncepcji Szasza na dzisiejszą psychiatrię i akcentuje, że pomimo zasłużonej krytyki należał on do tych myślicieli, którzy dobitnie, choć nieraz skrajnie, wyrazili najważniejsze epistemologiczne i etyczne problemy współczesnej psychiatrii, co czyni jego myśl ważną także dla współczesnej psychiatrii.
Probabilistic Oblique Impact Analysis of Functionally Graded Plates – A Multivariate Adaptive Regression Splines Approach
Authors: Karsh P. K. , Thakkar Bindi , Kumar R. R. , Vaishali  , Dey Sudip
Published: October 2021

Purpose: To investigate the probabilistic low-velocity impact of functionally graded (FG) plate using the MARS model, considering uncertain system parameters.
Design/methodology/application: The distribution of various material properties throughout FG plate thickness is calculated using power law. For finite element (FE) formulation, isoparametric elements with eight nodes are considered, each component has five degrees of freedom. The combined effect of variability in material properties such as elastic modulus, modulus of rigidity, Poisson’s ratio, and mass density are considered. The surrogate model is validated with the FE model represented by the scatter plot and the probability density function (PDF) plot based on Monte Carlo simulation (MCS).
Findings: The outcome of the degree of stochasticity, impact angle, impactor’s velocity, impactor’s mass density, and point of impact on the maximum value of contact force (CFmax
), plate deformation (PDmax), and impactor deformation (IDmax
) are determined. A convergence study is also performed to determine the optimal number of the constructed MARS model’s sample size.
Originality/value: The results illustrate the significant effects of uncertain input parameters on FGM plates’ low-velocity impact responses by employing a surrogate-based MARS model.
Antioxidant compounds from marine seaweeds and their mechanism of action
Authors: Debnath Trishna , Kim Eun-Kyung , Lee Kwang-Geun , Debnath Narayan Chandra , Mathur Ramkumar
Published: October 2021

Investigation of natural products has moved toward marine environments as they are a source of many biologically active agents. The natural antioxidant compounds isolated from seaweeds provide a valuable contribution to the innovation of new drugs for chronic diseases associated with
oxidative stress. While the antioxidant activity and nutritional benefits of various seaweed products are well recognized, their proper utilization as antioxidants remains at initial stages that require further investigative studies. This review provides a detailed study of isolated antioxidant
compounds from seaweeds and their major mechanism of action by focusing on the reports from 2015 to 2019. The report discusses various active antioxidant compounds, including phenolics (e.g., phlorotannins), polysaccharides, and pigments with proven benefits against oxidative stress-related
diseases, especially carotenoids, from the aspect of benefits to human health.
Segmentation-Less, Automated, Vascular Vectorization
Authors: Mihelic Samuel A. , Sikora William A. , Hassan Ahmed M. , Williamson Michael R. , Jones Theresa A. , Dunn Andrew K.
Published: October 2021

Recent advances in two-photon fluorescence microscopy (2PM) have allowed large scale imaging and analysis of blood vessel networks in living mice. However, extracting network graphs and vector representations for the dense capillary bed remains a bottleneck in many applications. Vascular vectorization is algorithmically difficult because blood vessels have many shapes and sizes, the samples are often unevenly illuminated, and large image volumes are required to achieve good statistical power. State-of-the-art, three-dimensional, vascular vectorization approaches often require a segmented (binary) image, relying on manual or supervised-machine annotation. Therefore, voxel-by-voxel image segmentation is biased by the human annotator or trainer. Furthermore, segmented images oftentimes require remedial morphological filtering before skeletonization or vectorization. To address these limitations, we present a vectorization method to extract vascular objects directly from unsegmented images without the need for machine learning or training. The Segmentation-Less, Automated, Vascular Vectorization (SLAVV) source code in MATLAB is openly available on GitHub. This novel method uses simple models of vascular anatomy, efficient linear filtering, and vector extraction algorithms to remove the image segmentation requirement, replacing it with manual or automated vector classification. Semi-automated SLAVV is demonstrated on three in vivo 2PM image volumes of microvascular networks (capillaries, arterioles and venules) in the mouse cortex. Vectorization performance is proven robust to the choice of plasma- or endothelial-labeled contrast, and processing costs are shown to scale with input image volume. Fully-automated SLAVV performance is evaluated on simulated 2PM images of varying quality all based on the large (1.4×0.9×0.6 mm3 and 1.6×108 voxel) input image. Vascular statistics of interest (e.g. volume fraction, surface area density) calculated from automatically vectorized images show greater robustness to image quality than those calculated from intensity-thresholded images.
Engineering gene overlaps to sustain genetic constructs in vivo
Authors: Decrulle Antoine L. , Frénoy Antoine , Meiller-Legrand Thomas A. , Bernheim Aude , Lotton Chantal , Gutierrez Arnaud , Lindner Ariel B.
Published: October 2021

Evolution is often an obstacle to the engineering of stable biological systems due to the selection of mutations inactivating costly gene circuits. Gene overlaps induce important constraints on sequences and their evolution. We show that these constraints can be harnessed to increase the stability of costly genes by purging loss-of-function mutations. We combine computational and synthetic biology approaches to rationally design an overlapping reading frame expressing an essential gene within an existing gene to protect. Our algorithm succeeded in creating overlapping reading frames in 80% ofE. coligenes. Experimentally, scoring mutations in both genes of such overlapping construct, we found that a significant fraction of mutations impacting the gene to protect have a deleterious effect on the essential gene. Such an overlap thus protects a costly gene from removal by natural selection by associating the benefit of this removal with a larger or even lethal cost. In our synthetic constructs, the overlap converts many of the possible mutants into evolutionary dead-ends, reducing the evolutionary potential of the system and thus increasing its stability over time.
Plant phenomics & precision agriculture simulation of winter wheat growth by the assimilation of unmanned aerial vehicle imagery into the WOFOST model
Authors: Yang Tianle , Zhang Weijun , Zhou Tong , Wu Wei , Liu Tao , Sun Chengming
Published: October 2021

The aim of this study is to optimize the simulation result of the WOFOST model and explore the possibility of assimilating unmanned aerial vehicle (UAV) imagery into this model. Field images of wheat during its key growth stages are acquired with a UAV, and the corresponding leaf area index (LAI), biomass, and final yield are experimentally measured. LAI data is retrieved from the UAV imagery and assimilated into a localized WOFOST model using least squares optimization. Sensitive parameters, i.e., specific leaf area (SLATB0, SLATB0.5, SLATB2) and maximum CO2 assimilation rate (AMAXTB1, AMAXTB1.3) are adjusted to minimize the discrepancy between the LAI obtained from the model simulation and inversion of the UAV data. The results show that the assimilated model provides a better estimation of the growth and development of winter wheat in the study area. The R2, RMSE, and NRMSE of winter wheat LAI simulated with the assimilated WOFOST model are 0.8812, 0.49, and 23.5% respectively. The R2, RMSE, and NRMSE of the simulated yield are 0.9489, 327.06 kg·hm−2, and 6.5%. The accuracy in model simulation of winter wheat growth is improved, which demonstrates the feasibility of integrating UAV data into crop models.
The effect of age on the heart rate variability of healthy subjects
Authors: Garavaglia Leopoldo , Gulich Damián , Defeo Magdalena M. , Thomas Mailland Julieta , Irurzun Isabel M.
Published: October 2021

In this work we study the characteristics of heart rate variability (HRV) as a function of age and gender. Our analysis covers a wider age range than that studied so far. It includes results previously reported in the literature and reveals behaviours not reported before. We can establish basic scale relationships in different HRV measurements. The mean value of the RR intervals shows a power-law behaviour independent of gender. Magnitudes such as the standard deviation or pNN50 show abrupt changes at around the age of 12 years, and above that age they show gender dependence, which mainly affects short-time (or high frequency) scales. We present a unified analysis for the calculation of the non-linear α and β parameters. Both parameters depend on age; they increase in the extremes of life and reach a minimum at around one year of age. These gender-independent changes occur at low frequencies and in scale ranges that depend on age. The results obtained in this work are discussed in terms of the effects of basal metabolic rate, hormonal regulation, and neuronal activity on heart rate variability. This work finally discusses how these findings influence the interpretation of HRV measurements from records of different lengths.
Analyzing protest mobilization on Telegram: The case of 2019 Anti-Extradition Bill movement in Hong Kong
Authors: Urman Aleksandra , Ho Justin Chun-ting , Katz Stefan
Published: October 2021

Online messaging app Telegram has increased in popularity in recent years surpassing Twitter and Snapchat by the number of active monthly users in late 2020. The messenger has also been crucial to protest movements in several countries in 2019-2020, including Belarus, Russia and Hong Kong. Yet, to date only few studies examined online activities on Telegram and none have analyzed the platform with regard to the protest mobilization. In the present study, we address the existing gap by examining Telegram-based activities related to the 2019 protests in Hong Kong. With this paper we aim to provide an example of methodological tools that can be used to study protest mobilization and coordination on Telegram. We also contribute to the research on computational text analysis in Cantonese—one of the low-resource Asian languages,—as well as to the scholarship on Hong Kong protests and research on social media-based protest mobilization in general. For that, we rely on the data collected through Telegram’s API and a combination of network analysis and computational text analysis. We find that the Telegram-based network was cohesive ensuring efficient spread of protest-related information. Content spread through Telegram predominantly concerned discussions of future actions and protest-related on-site information (i.e., police presence in certain areas). We find that the Telegram network was dominated by different actors each month of the observation suggesting the absence of one single leader. Further, traditional protest leaders—those prominent during the 2014 Umbrella Movement,—such as media and civic organisations were less prominent in the network than local communities. Finally, we observe a cooldown in the level of Telegram activity after the enactment of the harsh National Security Law in July 2020. Further investigation is necessary to assess the persistence of this effect in a long-term perspective.
Trypsin induces an aversive response in zebrafish by PAR2 activation in keratinocytes
Authors: Alsrhani Abdullah , Raman Revathi , Jagadeeswaran Pudur
Published: October 2021

Previously we have shown that trypsin, a protein typically involved in digestion, is released from gills of both fresh and saltwater fishes into surrounding water under stress or injury. We have also shown that each species produces trypsin with different specific activities. In this report, using zebrafish as a model, we identified that trypsin induces an aversive response in zebrafish larvae and adult zebrafish. Since Protease-Activated Receptor 2 (PAR2) responds to trypsin, we tested whether the aversive response is dependent on the activation of PAR2 located on the zebrafish skin cells. Zebrafish larvae treated separately with neomycin and zinc sulfate also showed aversive response indicating neuromast, and olfactory cells are not involved in this aversion. Cultured keratinocytes from zebrafish showed a response to trypsin. Zebrafish larvae subjected to knockdown of par2a also exhibited reduced escape response. Similarly, par2a-deficient mutant larvae displayed no response to trypsin. Since it has been shown that stress activates PAR2 and sends signals to the brain as shown by the increased c-fos expression, we tested c-fos expression in adult zebrafish brains after trypsin treatment of adults and found enhanced c-fos expression by qRT-PCR. Taken together, our results show that the trypsin activates PAR2 on keratinocytes signaling the brain, and this pathway of trypsin-induced escape response will provide a unique communication mechanism in zebrafish. Furthermore, since PAR2 activation also occurs in pain/pruritus sensing, this model might be useful in elucidating components of signaling pathways in pain/pruritus.
Sediment transport modeling in non-deposition with clean bed condition using different tree-based algorithms
Authors: Gul Enes , Safari Mir Jafar Sadegh , Torabi Haghighi Ali , Danandeh Mehr Ali
Published: October 2021

To reduce the problem of sedimentation in open channels, calculating flow velocity is critical. Undesirable operating costs arise due to sedimentation problems. To overcome these problems, the development of machine learning based models may provide reliable results. Recently, numerous studies have been conducted to model sediment transport in non-deposition condition however, the main deficiency of the existing studies is utilization of a limited range of data in model development. To tackle this drawback, six data sets with wide ranges of pipe size, volumetric sediment concentration, channel bed slope, sediment size and flow depth are used for the model development in this study. Moreover, two tree-based algorithms, namely M5 rule tree (M5RT) and M5 regression tree (M5RGT) are implemented, and results are compared to the traditional regression equations available in the literature. The results show that machine learning approaches outperform traditional regression models. The tree-based algorithms, M5RT and M5RGT, provided satisfactory results in contrast to their regression-based alternatives withRMSE= 1.184 andRMSE= 1.071, respectively. In order to recommend a practical solution, the tree structure algorithms are supplied to compute sediment transport in an open channel flow.
Demographic responses of a threatened, low-density ungulate to annual variation in meteorological and phenological conditions
Authors: DeMars Craig A. , Gilbert Sophie , Serrouya Robert , Kelly Allicia P. , Larter Nicholas C. , Hervieux Dave , Boutin Stan
Published: October 2021

As global climate change progresses, wildlife management will benefit from knowledge of demographic responses to climatic variation, particularly for species already endangered by other stressors. In Canada, climate change is expected to increasingly impact populations of threatened woodland caribou (Rangifer tarandus caribou) and much focus has been placed on how a warming climate has potentially facilitated the northward expansion of apparent competitors and novel predators. Climate change, however, may also exert more direct effects on caribou populations that are not mediated by predation. These effects include meteorological changes that influence resource availability and energy expenditure. Research on other ungulates suggests that climatic variation may have minimal impact on low-density populations such as woodland caribou because per-capita resources may remain sufficient even in “bad” years. We evaluated this prediction using demographic data from 21 populations in western Canada that were monitored for various intervals between 1994 and 2015. We specifically assessed whether juvenile recruitment and adult female survival were correlated with annual variation in meteorological metrics and plant phenology. Against expectations, we found that both vital rates appeared to be influenced by annual climatic variation. Juvenile recruitment was primarily correlated with variation in phenological conditions in the year prior to birth. Adult female survival was more strongly correlated with meteorological conditions and declined during colder, more variable winters. These responses may be influenced by the life history of woodland caribou, which reside in low-productivity refugia where small climatic changes may result in changes to resources that are sufficient to elicit strong demographic effects. Across all models, explained variation in vital rates was low, suggesting that other factors had greater influence on caribou demography. Nonetheless, given the declining trajectories of many woodland caribou populations, our results highlight the increased relevance of recovery actions when adverse climatic conditions are likely to negatively affect caribou demography.