bluuebunny/crossref_metadata_2025 huggingface dataset:
CCSer2 gates dynein activity at the cell periphery
Authors: Zang Juliana L. , Gibson Daytan , Zheng Ann-Marie , Shi Wanjing , Gillies John P. , Stein Chris , Drerup Catherine M. , DeSantis Morgan E.
Published: June 2024

Cytoplasmic dynein-1 (dynein) is a microtubule-associated, minus end-directed motor that traffics hundreds of different cargos. Dynein must discriminate between cargos and traffic them at the appropriate time from the correct cellular region. How dynein’s trafficking activity is regulated in time or cellular space remains poorly understood. Here, we identify CCSer2 as the first known protein to gate dynein activity in the spatial dimension. CCSer2 promotes the migration of developing zebrafish primordium cells and of cultured human cells by facilitating the trafficking of cargos that are acted on by cortically localized dynein. CCSer2 inhibits the interaction between dynein and its regulator Ndel1 exclusively at the cell periphery, resulting in localized dynein activation. Our findings suggest that the spatial specificity of dynein is achieved by the localization of proteins that disinhibit Ndel1. We propose that CCSer2 defines a broader class of proteins that activate dynein in distinct microenvironments via Ndel1 inhibition.
Engineering and revealing Dirac strings in spinor condensates
Authors: Xu Gui-Sheng , Jain Mudit , Zhou Xiang-Fa , Guo Guang-Can , Amin Mustafa A. , Pu Han , Zhou Zheng-Wei
Published: June 2024

Artificial monopoles have been engineered in various systems, yet there has been no systematic study of the singular vector potentials associated with the monopole field. We show that the Dirac string, the line singularity of the vector potential, can be engineered, manipulated, and made manifest in a spinor atomic condensate. We elucidate the connection among spin, orbital degrees of freedom, and the artificial gauge, and show that there exists a mapping between the vortex filament and the Dirac string. We also devise a proposal where preparing initial spin states with relevant symmetries can result in different vortex patterns, revealing an underlying correspondence between the internal spin states and the spherical vortex structures. Such a mapping also leads to a new way of constructing spherical Landau levels, and monopole harmonics. Our observation provides insights into the behavior of quantum matter possessing internal symmetries in curved spaces.

Published by the American Physical Society
2024
Corporate board characteristics and CSR budget of selected Bangladeshi banks: moderating role of corporate reputation
Authors: Hosain Md Sajjad
Published: June 2024

Purpose

This study explores the relationships between corporate board characteristics (CBCs) and corporate social responsibility budget (CSRB) of selected Bangladeshi banks. CSRB was regarded as the sole dependent variable. In contrast, CBCs was separated into three independent constructs: board members' age (BMA), board members’ educational level (BMEL) and the number of board meetings per year (NBMY). A single moderator, corporate reputation (CR), was used to assess the moderating impact on the direct relationships.

Design/methodology/approach

Annual reports from 2017 to 2021 (5 years) of 25 selectively listed Bangladeshi banks were used as study samples. Further, the researcher conducted informal interviews with 251 board members of those selected banks using a semi-structured questionnaire. The study used “multiple regression analysis” to evaluate the moderating effects on the three direct relationships and “Pearson's correlation coefficient” to assess the immediate impacts.

Findings

After analysis, the results revealed that all the three independent components, BMA, BMEL and NBMY, have substantial positive relationships with the dependent variable, CSRB. Moreover, it was identified that CR can moderate (strengthen) all the three direct relationships. 

Originality/value

Corporate governance (CG) and CSR are two hot topics both in academia and practice. This study highlighted the corporate board characteristics and CSR budget, two new dimensions of CG literature that are required to be paid more attention to. The researcher expects this study to enhance the literature focused on these newer dimensions of CG that might benefit both academics and practitioners.
Rural–urban differences in the intergenerational transmission of cognitive capabilities in China: evidence from a Northwestern province of China
Authors: Wang Lei , Emmers Dorien , Sylvia Sean , Bai Yu , Rozelle Scott
Published: June 2024

Purpose

Literature has shown that the intergenerational transmission of cognitive abilities is stronger for children raised in more advantaged environments. However, there has never been an empirical investigation of this pattern in China. This study examines differences in the intergenerational transmission of cognitive capabilities among mothers and young children in urban and rural subpopulations in China and investigates whether these differences are driven by differences in parental investment in the home environment.

Design/methodology/approach

Data collected from randomly selected 6- to 36-month-old babies and their mothers in a Northwestern province in China was used. Child capabilities were assessed by the Bayley Scales of Infant and Toddler Development (3rd edition). Maternal intelligence quotient (IQ) scores were assessed with the Raven’s Progressive Matrices test. The non-parametric regression methods were used to construct the factor scores of child capabilities. The ordinary least squares (OLS) models were employed to investigate the relations between child cognition, maternal IQ and parental investment.

Findings

In urban households, where most children are raised in a positive home environment, child cognitive scores are strongly correlated with maternal IQ. In rural households, where parental investments are lower and more variable, child cognitive scores are not significantly correlated with maternal IQ but are predicted by differences in parental investments in a cognitively stimulating home environment.

Originality/value

This study provides a unique contribution by utilizing rural–urban disparities in China as a unique natural experiment to investigate differences in the transmission of cognitive capabilities across socioeconomic status (SES). It also provides the first empirical evidence of SES differences in the intergenerational transmission of cognitive capabilities in a developing country. This study reveals that intergenerational mother–child cognition associations are disrupted by poor parental investment in rural households but not in urban households.
To invest or not to invest in digital initiatives? An exploratory examination of procedures, evaluation criteria and barriers
Authors: Kraus Patrick , Kappl Julian , Schlegel Dennis
Published: June 2024

Purpose

Due to the disruptive nature of digital transformation, firms can hardly ignore the further digitalisation of processes and business models. Implementing such initiatives triggers enormous investments in infrastructure and software, making the evaluation of digital investments crucial for a firm’s competitive situation.

Design/methodology/approach

Given the dynamics and uncertainties inherent in digital transformation, a qualitative, inductive research approach based on semi-structured interviews with high-level finance executives has been employed.

Findings

Our findings indicate widespread dissatisfaction with traditional investment appraisal methods for evaluating digital investments. Data also suggest that non-financial considerations are frequently taken into account, albeit implicitly, as participants struggled to clearly conceptualize these criteria.

Originality/value

The literature indicates important research gaps regarding the applicability and usage of traditional, predominantly financial, investment appraisal methods in digital contexts. This research enhances our understanding of digital investment evaluation, by (i) developing an exploratory conceptual framework of potential qualitative evaluation criteria and (ii) providing an in-depth and detailed understanding of the barriers to implementing investment appraisal methods.
Lights! Camera! Action! Unveiling film tourists' profile
Authors: Aguilar-Rivero Minerva , Solano-Sánchez Miguel Ángel , López-Guzmán Tomás , Moral-Cuadra Salvador
Published: June 2024

Purpose

This research aims to analyse the degree of influence that viewing frequency and preferences for movies and television (TV)/platforms series and aspects related to movie destinations have on the socio-demographic profile of the tourist interested in film tourism.

Design/methodology/approach

An artificial neural network (ANN) is used, in which the input values correspond to the questions asked through the questionnaire and the estimated output values are the socio-demographic profile.

Findings

Low frequency of attendance at movie theatres, especially amongst the youngest. Profiles with a higher level of education value the cultural elements in the destination more. A high-income profile is revealed that considers the visit to the film destination as a secondary reason for their trip since they value the proximity to the main holiday destination and show that this visit does not bring them greater satisfaction than other activities. Experiential tourism is another aspect valued by the profiles with the highest income, which can be easily related to film tourism.

Originality/value

Customised input values estimate specific output values, building “identikits” of tourists based on the responses incorporated into the model and easily customisable by the researcher, making them useful in film tourism products and service elaboration. Although this method has been used successfully on other tourist profile types, no studies of this type applied to film tourism were found, and this work aims to pioneer this line.
In pursuit of decision comprehensiveness: navigating goal heterogeneity
Authors: Ergene Erim , Floyd Steven W.
Published: June 2024

Purpose

Decision comprehensiveness is an important process in determining the outcomes of strategic decision-making. While recent research began to explore its individual level antecedents, a fundamental aspect of organizational life, heterogeneous goals, have not been investigated for their effects on comprehensiveness. In this study, our purpose is to study the impact of goal heterogeneity on decision comprehensiveness and explore behavioral integration as a potential mediator in this relationship.

Design/methodology/approach

To test our hypotheses, we utilize a survey-based study with a sample of teams undertaking a business simulation. Our longitudinal data collection process captures team data across the initial-, mid-, and the ending-stages of the simulation.

Findings

Our findings show that goal heterogeneity negatively impacts behavioral integration and decision comprehensiveness. Moreover, the negative impact of goal heterogeneity on decision comprehensiveness is mediated through behavioral integration.

Originality/value

Given that many strategic decisions are undertaken by groups of individuals, it is imperative to understand the factors that impact team-level decision-making processes. Extending the literature, we empirically show the negative effects of goal heterogeneity on decision comprehensiveness. While doing so, we also show that behavioral integration – a team trait that can endure over time, as opposed to a one-time state – can be crucial in dampening this negative effect. Our findings suggest researchers, and managers, to be cautious in assuming decision comprehensiveness may easily be achieved in any given team context.
Manager‐specific manipulation of tone and stock price synchronicity
Authors: Jiang Miao , Zhu Bo , Li Luxi
Published: June 2024

Using a sample of Chinese listed firms from 2008 to 2020, we find that manager‐specific upward manipulation of tone in the Management Discussion and Analysis (MD&A) section is associated with greater stock price synchronicity. This suggests that upward tone manipulation decreases the stock's idiosyncratic information content. This relationship between abnormally positive tone and stock price synchronicity is negatively moderated by the firm's revenue growth rate, while investor irrational sentiment positively moderates this relationship. Additionally, positive tone manipulation significantly increases audit aggressiveness and decreases analyst optimism bias.
“My belly tickles! And my vulva too!”: Children's conversations about pleasure in Catalonia (Spain)
Authors: Malgosa Estel
Published: June 2024

In Spain, children's sexuality is a sensitive topic, and pleasure is its most controversial aspect, contradicting the notion of children's innocence. Through a new feminist materialist approach, I analyse the narratives of primary school children (aged 9–11) about pleasant bodily sensations to explore their capacity for pleasure and the assemblage of elements that facilitate it. Additionally, I describe the forces that stabilise these assemblages and those that destabilise them. The findings suggest that leaving pleasure out of relationships and sex education reproduces gender and age inequalities, making visible the need to recognise children as subjects of sexuality and pleasure.
Advancements in minimally invasive endoscopic treatment: Navigating deeper layers for upper gastrointestinal lesion
Authors: Shimamura Yuto , Inoue Haruhiro , Yamamoto Kazuki , Owada Kaori , Tanaka Ippei
Published: June 2024

The field of minimally invasive endoscopic treatment has seen a continual progression, marked by significant advancements in treatment devices and the refinement of endoscopic techniques. While endoscopic resection has become the standard for treating superficial gastrointestinal neoplasms, a proactive approach becomes imperative when dealing with lesions that extend beyond the submucosal layer and deeper into the muscularis propria. The ongoing evolution of endoscopic closure techniques has facilitated the introduction of advanced procedures such as endoscopic muscularis dissection, endoscopic subserosal dissection, and endoscopic full‐thickness resection. This evolution is achieved by the commitment to improve the efficacy and precision in treating challenging lesions. Nevertheless, there is currently a lack of definitive guidelines or consensus regarding the specifics of deeper layer dissection. Drawing from prior research and clinical insights, this review discusses indications, techniques, clinical outcomes, and future perspectives of deeper layer dissection.
Embodied Connection Work: The Role of the Lived Body in Routine Recreation in Extreme Contexts
Authors: Sele Kathrin , Danner‐Schröder Anja , Mahringer Christian A.
Published: June 2024

Extreme events pose major challenges for the performance of routines as they threaten the continuation of work in all its forms. This paper uses an embodiment perspective to examine a routine recreation process in a fine‐dining zero‐waste restaurant whose routines were completely disrupted by the COVID‐19 pandemic. Zooming in on the role of the lived body, our study reveals the importance of ‘embodied connection work’ for the recreation of a new set of routines. We show how this active process of making connections between actors and actions consists of ‘embodied imagining’ and ‘embodied protecting’. Together, these interrelated practices enable the reintegration of stakeholders and the reassembling of what matters to the restaurant owners. Our study contributes to research at the intersection of routines and extreme contexts in three ways: (1) we move away from considering the body as a trained object and focus instead on the lived body and its role in performing and patterning and, hence, in recreating routines; (2) we unpack how novel roles emerge through embodied connection work as new and existing connections are forged; and (3) we conceptualize the relationship between routines and context as mutually constitutive suggesting that actions are situated through the lived body.
Quantification of localised strains induced within a granular medium by a biphasic flow via digital image correlation
Authors: Al Nemer Rana , Réthoré Julien , Sciarra Giulio
Published: June 2024

Biphasic flow propagating through a granular medium can be established as an unstable infiltration and can be precursors of nonnegligible deformations. Capturing such infiltration through the lens of a high‐resolution camera, full‐field strain maps are determined via digital image correlation (DIC). However, this image analysis technique is based on the fundamental assumption of grey level conservation between the reference and deformed images. In this paper, DIC algorithm is recalled, and suitable controlling parameters are introduced to improve the accuracy of the output displacement fields and to remove the grey level variations induced by an air‐water flow percolating through a Fontainebleau sand. In addition, an in‐depth investigation on the full‐field volumetric strain maps is conducted in order to extract the hidden relationship between the front propagation and the strains evolution.
Brumas de la memoria: Del olvido y el recuerdo a la recuperación de la vida cotidiana de Falan, Tolima
Authors: Hernández Moreno Manuel Andrés
Published: June 2024

En Colombia, la información existente frente a los estudios de la memoria y la vida cotidiana es limitada; porque la mayoría de las investigaciones que giran en torno a la memoria enfatizan en la memoria histórica, es decir, a aquellas que tienen que ver con las relaciones que se dan en los marcos de los conflictos, principalmente los que tienen que ver con la violencia, dejando de lado los estudios relacionados con las experiencias y recuerdos, manifestados en las formas socioculturales de las poblaciones en el pasado.
Además, la mayoría de trabajos de reconstrucción del pasado de los municipios en el territorio colombiano rescatan los fragmentos de su historia a través de una Historia oficial, que narra algunos hechos relevantes y personajes importantes para su población, obviando la reconstrucción de su pasado por medio de las historias de todos los días, de sus gentes, de sus relaciones personales y de la construcción de significados en su vida diaria, que potencia la vida cotidiana que los circunda, y que hace parte de su propio devenir histórico.
Y es en este sentido que apareció la investigación doctoral “Las brumas de la memoria: Del olvido y el recuerdo a la recuperación de la Vida cotidiana de Falan (Tolima)”, que marcó su camino bajo la línea de investigación de “Memoria, experiencia y creencia” del Doctorado en Estudios sociales de la Universidad Distrital Francisco José de Caldas de Bogotá (Colombia).
Para este caso, se correlacionaron los estudios de Memoria y los estudios de la Vida cotidiana, con el fin de dar vida a una reconstrucción diferente del pasado, que permitió mostrar la presencia de la vida cotidiana de esos hombres y mujeres del común, que ha formado parte del pasado de las poblaciones, y que, a partir de las distintas formas de ser, hacer y vivir, ha sido inadvertido en la historia oficial de los pueblos, quedando en ocasiones relegado al olvido.
Conviene subrayar que el espacio geográfico en el que se enfocó la investigación fue Falan, municipio ubicado al norte del departamento del Tolima, en Colombia. Un lugar que se fundó bajo las marcas de la búsqueda del oro y la plata en la cordillera central colombiana, y que, escondido en las cumbres de sus montañas, delineó unas formas de construir la vida cotidiana de sus habitantes.
Equivalent Properties of Interfacial Void Defects at the CFRTP-Adhesive Interface and Their Detrimental Effects on the Bonding Performance of Metal-CFRTP Dissimilar Joints
Authors: Qiao Yao , Shin Yongsoon , Ko Seunghyun , Samanta Avik , Seffens Robert J. , Ramos Jose L. , Merkel Daniel R. , Shahwan Khaled W. , Simmons Kevin L.
Published: June 2024

This paper revealed the detrimental effects of micro-scale air interfacial voids on the debonding at the interface of carbon-fiber-reinforced polyphthalamide (CFRPPA) and thermoset adhesive, representing a weak adherend-adhesive interface, within a dissimilar joint made of an aluminum alloy and a CFRPPA. The reduced lap shear strength of the joint, due to different void area fractions at the CFRPPA-adhesive interface, can be computationally described by using equivalent interfacial properties in the modeling to avoid the explicit modeling of the micro-scale interfacial voids. Such equivalent interfacial properties (e.g., interfacial normal strength, etc.) was found to have a non-linear relationship with respect to interfacial void area fraction as well as lap shear strength. This work has practical applications by utilizing equivalent interfacial properties for the analytical and/or computational design(s) of adhesively-bonded joints.
Flexural Strength and Shear Properties of Sandwich Composites Made of 3D-Printed Cores
Authors: Raihan Gazi Abu , Chakravarty Uttam K.
Published: June 2024

Sandwich composites have gained significant attention in recent years due to their exceptional strength-to-weight ratio, bending stiffness-to-weight ratio, higher energy dissipation in impact, and versatility in applications. Due to the fatigue degradation and shear failure in conventional cores, developing novel sandwich structures made of alternative cores carries significant scientific importance in many engineering areas. This study explores the utilization of 3D Printed Acrylonitrile Butadiene Styrene (ABS) thermoplastic cores in sandwich structures to improve flexural and shear strength. The research aims to develop new sandwich composites having lightweight yet robust material properties using additive manufacturing (AM) and vacuum-assisted resin infusion process. To evaluate the flexural and shear strengths, ASTM standard sample specimens are prepared where 3-point bending tests are employed to assess the flexural strength and analyze the shear strength. The results are compared with balsa and PET foam cores having the same fiber. The findings exhibit improved flexural and shear strength in 3D Printed ABS cores compared to foam-cored composites. ABS cores also exhibit excellent load bearing while the composite skins provide the necessary stiffness in reinforcement.
Exploring Failure of Adhesively-Bonded Joints With Different Void Sizes at the Same Void Volume Fraction Through a Micro-Scale Numerical Modeling
Authors: Qiao Yao , Ko Seunghyun , Shin Yongsoon , Simmons Kevin L.
Published: June 2024

This paper studied the effects of void sizes on the failure behavior of adhesively-bonded materials under global shear via micro-scale computational modeling. The numerical results indicate that large void sizes with increased distances between them at the same void volume fraction can alleviate the reduced joint strength of a weaker adherend-adhesive interface caused by interfacial voids. However, this is not the case for an adherend-adhesive interface with the interfacial tensile strength being sufficiently higher than the adhesive strength, showing the negligible effect on the joint strength due to various void sizes and the amount of interfacial voids. This preliminary investigation provides insightful information for scaling up the void size in the macro-scale computational modeling of joints, and enhances the understanding of the micro-mechanical adhesion in adherend-adhesive interfaces with different levels of bonding.
Design and Evaluation of Deployable Perovskite Solar Arrays Aboard Small Spacecraft
Authors: Suk So Yeon , Moritani Motoki , Sakamoto Hiraku , Horiuchi Tamotsu , Takabe Ryota , Hisada Yuko , Tokuda Rie , Mori Osamu , Toyota Hiroyuki , Miyazawa Yu , Matsushita Masanori , Nagai Kazuki , Ochi Atsuki , Mitchao Delburg , Takeda Yuki , Yasuhara Mitsuhiko , Saito Soma , Tomura Takashi
Published: June 2024

A self-deployable membrane structure with integrated perovskite solar arrays was developed for installation aboard OrigamiSat-2, a 3U CubeSat (10 cm × 10 cm × 34 cm) selected by the Japan Aerospace Exploration Agency’s Innovative Satellite Technology Demonstration-4 program. The textile membrane (50 cm × 50 cm), inspired by the origami flasher model, is stowed within a volume of 1U (10 cm × 10 cm × 8 cm) and deployed in orbit using composite booms. Two solar arrays, each consisting of two flexible perovskite solar cells (35.4 mm × 75 mm × 315 μm), are attached to the surface of the membrane. This paper will describe the following development activities in detail: (i) Structural prototypes of the membrane solar arrays were fabricated with dummy solar cells and cables. To ensure high packing efficiency and reliable deployment, the prototypes were subjected to a series of stowage and deployment tests. Design modifications were made based on the test results; (ii) The performance of the perovskite solar cells was evaluated by measuring their current-voltage characteristics under a solar simulator; (iii) Potential degradation in solar cell performance due to extreme space temperatures was assessed through thermal modeling and simulation. The design challenges and solutions, as well as compromises that were necessary to meet satellite requirements, may provide insights for future development of deployable power systems on small satellites.
Layer-Wise Modeling of Temperature Distributions and Degree of Cure to Evaluate Process-Induced Deformation and Residual Stress
Authors: Zappino Enrico , Petrolo Marco , Santori Martina
Published: June 2024

In this work, a cure simulation based on a one-dimensional thermochemical model is used to predict the evolution of temperature and degree of cure along the thickness of the composite component during the curing cycle. The one-dimensional heat transfer governing equation through the thickness is coupled with the curing kinetics of the thermoset composite material. Temperatures and degree of cure are then used for a thermo-mechanical analysis using layer-wise 1D elements based on the Carrera Unified Formulation (CUF).

Using 1D models allows for computational costs and enables fast numerical analyses. The impact that thickness has on process-induced stresses and strains is evaluated. In particular, displacements for two flat plates with different layer thicknesses at the end of the process are calculated, and in-plane stress distributions are considered.

The results show the influence of a non-uniform degree of cure along the thickness, resulting in a consequent variation of material properties depending on the layer considered.
Variational Asymptotic Analysis of Beam-Like Cord-Rubber Composites
Authors: Jiang Fang , Yu Wenbin
Published: June 2024

Amount of engineering applications need steel cord to be embedded in a rubber matrix, which results in beam-like composite materials. Such materials feature a degree of lateral compliance and torsional flexibility while possessing high tensile stiffness. However, the currently available numerical approaches to analyze the effective material properties of such cord-rubber composites are computationally expensive. This paper proposes a novel approach based on an extended Variational Asymptotic Beam Sectional Analysis (VABS) theory which considers finite cross-sectional deformations. In the theory, the three-dimensional (3D) continuum is reduced to a one-dimensional (1D) beam analysis and a two-dimensional (2D) cross-sectional analysis featuring both geometric and material nonlinearities without unnecessary kinematic assumptions. As a result, the modeling and design of cord-rubber composites are dimensionally reduced to a composite beam cross-sectional domain. The present theory is implemented using the finite element method (FEM) in the VABS code, a general-purpose beam cross-sectional analysis tool. An iterative method is applied to solve the finite warping field for the classical-type model using the Euler-Bernoulli beam theory. Hencky strain energy density and Neo-Hookean models describe cord wire and rubber matrix, respectively. Numerical examples demonstrate the capabilities of the present theory to capture the structural features of cord-rubber composites.
Thermal Characterization of Xenon Flash Lamp System for Automated Fiber Placement
Authors: Tavkari Devang , Davidson Paul
Published: June 2024

Carbon fiber Thermoplastic pre-preg tape laydown and consolidation used with Automated Fiber Placement (AFP) required high temperatures to melt the matrix. There are a few methods that can reach the desired temperature. Hot-gas torch, laser heating, and arc-flash lamp-based heating systems are the most popular among them. Among the three, arc-flash lamp-based heating provides the most versatility regarding heating range and controllability. The lamp pulses light of high radiation intensity to heat the tow and substrate material during laydown rapidly. The irradiance output by the lamp is controlled by three process parameters, namely, (1) pulse width, (2) pulsing frequency, and (3) voltage. Further control can be achieved by changing the distance between the flash lamp and the tows. Therefore, the irradiance output from the lamp can be widely varied by changing the process and geometric parameters. This study aims to characterize the irradiance output from a xenon arc-flash heating system and its control parameters. The Xenon flash lamp’s irradiance response was used to map the irradiance profile on the tow and substrate within an Automated Fiber Placement machine. The impact of the AFP control parameters like roller compaction, tow layup speed, and positioning of xenon flash lamp on the irradiance profile of the tow and substrate were also examined in this study.
Zero Stiffness in Bellow-Type Soft Pneumatic Actuators for Modal Analysis of Flexible Aircraft Wings
Authors: Sprengholz Moritz , Meyer Patrick , Traub Hendrik , Hühne Christian
Published: June 2024

Modern aircraft designs with high aspect ratio wings pose challenges in accurately determining vibrational modes due to the increased flexibility of their wings. To accurately represent the large deformations occurring during flight in experimental modal analysis, actuators of low stiffness are needed, leading to the exploration of quasi-zero-stiffness vibration isolators. Such vibration isolators, combining positive and negative stiffness elements, lack the adaptability needed for varying wing load conditions. This study explores bellow-type soft pneumatic actuators, fabricated using 3D printing for iterative design and parameter studies, as a potential solution.

Initial experiments and simulations focused on the actuator stiffness for different geometric parameters and pressures. While simulations suggested that the occurrence of zero stiffness was primarily influenced by geometric parameters like the radius-to-height ratio, experimental results did not align with these findings, revealing discrepancies due to unmodeled boundary conditions. This misalignment highlighted the challenges in achieving the desired zero-stiffness characteristic in practical applications.

In conclusion, This study reveals that current bellow-type actuators fall short of the near-zero stiffness required for accurate modal analysis in flexible aircraft structures. Despite promising simulation results, experimental discrepancies highlight the need for improved designs and testing methods. Future research, potentially exploring rolling lobe actuators and refining 3D printing techniques, remains crucial in the ongoing quest for an ideal actuator in this domain.
Foreign Object Damage in Ytterbium Disilicate Based Environmental Barrier Coatings Modified for Oxidation Resistance
Authors: Hoffman Leland C. , Presby Michael J. , Harder Bryan J. , Stokes Jamesa L.
Published: June 2024

Environmental barrier coatings (EBCs) have been developed as an enabling technology for silicon carbide based ceramic matrix composites (CMCs) in gas turbine engines. Two of the key failure mechanisms identified in EBC systems are foreign object damage (FOD) and the oxidative growth of a SiO2 thermally grown oxide (TGO) layer that can lead to premature coating spallation. Previously the effects of FOD on NASA’s ytterbium disilicate based EBC were studied and recently it was shown that the addition of oxide modifiers resulted in improved oxidation resistance in the EBC. This work will compare FOD of the baseline ytterbium disilicate EBC to the that of the modified EBC. FOD was performed at room temperature using a 1.59 mm hardened steel ball with projectile velocities of 50–300 m/s. Additionally, the effects of oxidation via cyclic steam exposure prior to impact were investigated.
Advancing Environmental Sustainability Through Development of Wood Fiber Reinforced Polymer Composites
Authors: Siddique Ridwan , Billings Christopher , Sherwood Benjamin , Hall Joshua , Liu Yingtao
Published: June 2024

Integrating natural fibers into environmentally friendly polymers enhances mechanical properties, opening avenues for sustainable composites and advanced additive manufacturing (AM). This study incorporates wood fibers, a versatile cellulose resource, into a bio-based polylactic acid (PLA) polymer for 3D printing. This helps in the development of sustainable and recyclable green composites using fused deposition modeling (FDM). The printed composites undergo comprehensive characterization, assessing critical properties like density, porosity, microstructures, tensile modulus, and ultimate strength. Non-contact digital image correlation (DIC) technology analyzes local stress and strain concentration during mechanical testing. The validated FDM-based AM process is applied to print honeycombs, woven bowls, and frame bins, showcasing manufacturing capability. The mechanical performance and failure mechanism of 3D-printed honeycombs are evaluated under compressive loads using DIC. The research findings inform the design and optimization of AM-processed composite structures for a diverse array of engineering applications.
A 20-Year Systematic Review of Before- and After-School Physical Activity Research (2000–2020)
Authors: Marttinen Risto , Rodrigues Alba , Nuñez-Enriquez Oscar , Centeio Erin , Banville Dominique
Published: June 2024

Purpose: This systematic review aimed at identifying, categorizing, and analyzing peer-reviewed literature on organized before- and after-school (B&ASP) physical activity programs from 2000 to 2020. Methods: We analyzed 291 articles that fit the inclusion criteria from five databases. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses Guidelines were followed. Results: Research on B&ASPs has increased and been published in 157 journals across 26 countries. Most studies were quantitative. Most studies used a theoretical or conceptual framework and reported reliability, validity, and trustworthiness. Varied additional foci of impact were reported through different physical activities. However, physical activity was usually not measured. Interventions were 1–520 weeks long and conducted in different study contexts. Many studies targeted marginalized groups but did not utilize critical theory. Conclusion: Further studies should aim to better understand the nuances of B&ASPs, and critical theories could be useful. The lack of journals for B&ASP research limits scholars’ ability to move the field forward.
Artemisinins ameliorate polycystic ovarian syndrome by mediating LONP1-CYP11A1 interaction
Authors: Liu Yang , Jiang Jing-jing , Du Shao-yue , Mu Liang-shan , Fan Jian-jun , Hu Jun-chi , Ye Yao , Ding Meng , Zhou Wei-yu , Yu Qiu-han , Xia Yi-fan , Xu Hong-yu , Shi Yi-jie , Qian Shu-wen , Tang Yan , Li Wei , Dang Yong-jun , Dong Xi , Li Xiao-ying , Xu Cong-jian , Tang Qi-qun
Published: June 2024

Polycystic ovary syndrome (PCOS), a prevalent reproductive disorder in women of reproductive age, features androgen excess, ovulatory dysfunction, and polycystic ovaries. Despite its high prevalence, specific pharmacologic intervention for PCOS is challenging. In this study, we identified artemisinins as anti-PCOS agents. Our finding demonstrated the efficacy of artemisinin derivatives in alleviating PCOS symptoms in both rodent models and human patients, curbing hyperandrogenemia through suppression of ovarian androgen synthesis. Artemisinins promoted cytochrome P450 family 11 subfamily A member 1 (CYP11A1) protein degradation to block androgen overproduction. Mechanistically, artemisinins directly targeted lon peptidase 1 (LONP1), enhanced LONP1-CYP11A1 interaction, and facilitated LONP1-catalyzed CYP11A1 degradation. Overexpression of LONP1 replicated the androgen-lowering effect of artemisinins. Our data suggest that artemisinin application is a promising approach for treating PCOS and highlight the crucial role of the LONP1-CYP11A1 interaction in controlling hyperandrogenism and PCOS occurrence.
Highly pure DNA-encoded chemical libraries by dual-linker solid-phase synthesis
Authors: Keller Michelle , Petrov Dimitar , Gloger Andreas , Dietschi Bastien , Jobin Kilian , Gradinger Timon , Martinelli Adriano , Plais Louise , Onda Yuichi , Neri Dario , Scheuermann Jörg
Published: June 2024

The first drugs discovered using DNA-encoded chemical library (DEL) screens have entered late-stage clinical development. However, DEL technology as a whole still suffers from poor chemical purity resulting in suboptimal performance. In this work, we report a technique to overcome this issue through self-purifying release of the DEL after magnetic bead–based synthesis. Both the first and last building blocks of each assembled library member were linked to the beads by tethers that could be cleaved by mutually orthogonal chemistry. Sequential cleavage of the first and last tether, with washing in between, ensured that the final library comprises only the fully complete compounds. The outstanding purity attained by this approach enables a direct correlation of chemical display and encoding, allows for an increased chemical reaction scope, and facilitates the use of more diversity elements while achieving greatly improved signal-to-noise ratios in selections.
YABBY
and diverged
KNOX1
genes shape nodes and internodes in the stem
Authors: Tsuda Katsutoshi , Maeno Akiteru , Otake Ayako , Kato Kae , Tanaka Wakana , Hibara Ken-Ichiro , Nonomura Ken-Ichi
Published: June 2024

Plant stems comprise nodes and internodes that specialize in solute exchange and elongation. However, their boundaries are not well defined, and how these basic units arise remains elusive. In rice with clear nodes and internodes, we found that one subclade of class I
knotted1-like homeobox
(
KNOX1
) genes for shoot meristem indeterminacy restricts node differentiation and allows internode formation by repressing
YABBY
genes for leaf development and genes from another node-specific
KNOX1
subclade.
YABBY
s promote nodal vascular differentiation and limit stem elongation.
YABBY
and node-specific
KNOX1
genes specify the pulvinus, which further elaborates the nodal structure for gravitropism. Notably, this
KNOX1
subclade organization is specific to seed plants. We propose that nodes and internodes are distinct domains specified by
YABBY
–
KNOX1
cross-regulation that diverged in early seed plants.
Molecular mechanism of the ischemia-induced regulatory switch in mammalian complex I
Authors: Grba Daniel N. , Wright John J. , Yin Zhan , Fisher William , Hirst Judy
Published: June 2024

Respiratory complex I is an efficient driver for oxidative phosphorylation in mammalian mitochondria, but its uncontrolled catalysis under challenging conditions leads to oxidative stress and cellular damage. Ischemic conditions switch complex I from rapid, reversible catalysis into a dormant state that protects upon reoxygenation, but the molecular basis for the switch is unknown. We combined precise biochemical definition of complex I catalysis with high-resolution cryo–electron microscopy structures in the phospholipid bilayer of coupled vesicles to reveal the mechanism of the transition into the dormant state, modulated by membrane interactions. By implementing a versatile membrane system to unite structure and function, attributing catalytic and regulatory properties to specific structural states, we define how a conformational switch in complex I controls its physiological roles.
Remedy hope for polycystic ovary syndrome
Authors: Stener-Victorin Elisabet
Published: June 2024

Antimalarial suppresses ovarian androgen synthesis to relieve polycystic ovary syndrome
Motor vehicle collision (MVC) emergency department (ED) visits and hospitalisations in Ontario during the COVID-19 pandemic
Authors: Sammy Adrian , Medeiros Alexia , Batomen Brice , Rothman Linda , Harris M Anne , Harrington Daniel W , Macarthur Colin , Richmond Sarah A
Published: June 2024

Background

The COVID-19 pandemic policy response dramatically changed local transportation patterns. This project investigated the impact of COVID-19 policies on motor vehicle collision (MVC)-related emergency department (ED) visits and hospitalisations in Ontario.

Methods

Data were collected on MVC-related ED visits and hospitalisations in Ontario between March 2016 and December 2022. Using an interrupted time series design, negative binomial regression models were fitted to the pre-pandemic data, including monthly indicator variables for seasonality and accounting for autocorrelation. Extrapolations simulated expected outcome trajectories during the pandemic, which were compared with actual observed outcome counts using the overall per cent change and mean monthly difference. Data were modelled separately for vehicle occupants, pedestrians and cyclists (MVC and non-MVC injuries).

Results

There was a 31.5% decrease in observed ED visits (95% CI –35.4 to –27.3) and a 6.0% decrease in hospitalisations (95% CI −13.2 to 1.6) among vehicle occupants, relative to expected counts during the pandemic. Results were similar for pedestrians. Among cyclist MVCs, there was an increase in ED visits (12.8%, 95% CI −8.2 to 39.4) and hospitalisations (46.0%, 95% CI 11.6 to 93.6). Among non-MVC cyclists, there was also an increase in ED visits (47.0%, 95% CI 12.5 to 86.8) and hospitalisations (50.1%, 95% CI 8.2 to 101.2).

Conclusions

We observed fewer vehicle occupant and pedestrian collision injuries than expected during the pandemic. By contrast, we observed more cycling injuries than expected, especially in cycling injuries not involving motor vehicles. These observations may be attributable to changes in transportation patterns during the pandemic and increased uptake of recreational cycling.
NetConfEval: Can LLMs Facilitate Network Configuration?
Authors: Wang Changjie , Scazzariello Mariano , Farshin Alireza , Ferlin Simone , Kostić Dejan , Chiesa Marco
Published: June 2024

This paper explores opportunities to utilize Large Language Models (LLMs) to make network configuration human-friendly, simplifying the configuration of network devices & development of routing algorithms and minimizing errors. We design a set of benchmarks (NetConfEval) to examine the effectiveness of different models in facilitating and automating network configuration. More specifically, we focus on the scenarios where LLMs translate high-level policies, requirements, and descriptions (i.e., specified in natural language) into low-level network configurations & Python code. NetConfEval considers four tasks that could potentially facilitate network configuration, such as (i) generating high-level requirements into a formal specification format, (ii) generating API/function calls from high-level requirements, (iii) developing routing algorithms based on high-level descriptions, and (iv) generating low-level configuration for existing and new protocols based on input documentation. Learning from the results of our study, we propose a set of principles to design LLM-based systems to configure networks. Finally, we present two GPT-4-based prototypes to (i) automatically configure P4-enabled devices from a set of high-level requirements and (ii) integrate LLMs into existing network synthesizers.
Classification of Co-Manipulation Modus with Human-Human Teams for Future Application to Human-Robot Systems
Authors: Freeman Seth , Moss Shaden , Salmon John L. , Killpack Marc D.
Published: June 2024

Despite the existence of robots that can physically lift heavy loads, robots that can collaborate with people to move heavy objects are not readily available. This article makes progress toward effective human-robot co-manipulation by studying 30 human-human dyads that collaboratively manipulated an object weighing

\(27 \mathrm{kg}\)

without being co-located (i.e., participants were at either end of the extended object). Participants maneuvered around different obstacles with the object while exhibiting one of four modi–the manner or objective with which a team moves an object together–at any given time. Using force and motion signals to classify modus or behavior was the primary objective of this work. Our results showed that two of the originally proposed modi were very similar, such that one could effectively be removed while still spanning the space of common behaviors during our co-manipulation tasks. The three modi used in classification were
quickly
,
smoothly
and
avoiding obstacles
. Using a deep convolutional neural network (CNN), we classified three modi with up to 89% accuracy from a validation set. The capability to detect or classify modus during co-manipulation has the potential to greatly improve human-robot performance by helping to define appropriate robot behavior or controller parameters depending on the objective or modus of the team.
Can Coverage Criteria Guide Failure Discovery for Image Classifiers? An Empirical Study
Authors: Wang Zhiyu , Xu Sihan , Fan Lingling , Cai Xiangrui , Li Linyu , Liu Zheli
Published: June 2024

Quality assurance of deep neural networks (DNNs) is crucial for the deployment of DNN-based software, especially in mission- and safety-critical tasks. Inspired by structural white-box testing in traditional software, many test criteria have been proposed to test DNNs, i.e., to exhibit erroneous behaviors by activating new test units that have not been covered, such as new neurons, values, and decision paths. Many studies have been done to evaluate the effectiveness of DNN test coverage criteria. However, existing empirical studies mainly focused on measuring the effectiveness of DNN test criteria for improving the adversarial robustness of DNNs, while ignoring the correctness property when testing DNNs. To fill in this gap, we conduct a comprehensive study on 11 structural coverage criteria, 6 widely-used image datasets, and 9 popular DNNs. We investigate the effectiveness of DNN coverage criteria over natural inputs from four aspects: (1) the correlation between test coverage and test diversity; (2) the effects of criteria parameters and target DNNs; (3) the effectiveness to prioritize in-distribution natural inputs that lead to erroneous behaviors; and (4) the capability to detect out-of-distribution natural samples. Our findings include: (1) For measuring the diversity, coverage criteria considering the relationship between different neurons are more effective than coverage criteria that treat each neuron independently. For instance, the neuron-path criteria (i.e., SNPC and ANPC) show high correlation with test diversity, which is promising to measure test diversity for DNNs. (2) The hyper-parameters have a big influence on the effectiveness of criteria, especially those relevant to the granularity of test criteria. Meanwhile, the computational complexity is one of the important issues to be considered when designing deep learning test coverage criteria, especially for large-scale models. (3) Test criteria related to data distribution (i.e., LSA and DSA, SNAC, and NBC) can be used to prioritize both in-distribution natural faults and out-of-distribution inputs. Furthermore, for OOD detection, the boundary metrics (i.e., SNAC and NBC) are also effective indicators with lower computational costs and higher detection efficiency compared with LSA and DSA. These findings motivate follow-up research on scalable test coverage criteria that improve the correctness of DNNs.