bluuebunny/crossref_metadata_2025 huggingface dataset:
Nonlinear studies of modifications to general relativity: Comparing different approaches
Authors: Corman Maxence , Lehner Luis , East William E. , Dideron Guillaume
Published: October 2024

Studying the dynamical, nonlinear regime of modified theories of gravity remains a theoretical challenge that limits our ability to test general relativity. Here we consider two generally applicable, but approximate, methods for treating modifications to full general relativity that have been used to study binary black hole mergers and other phenomena in this regime, and compare solutions obtained by them to those from solving the full equations of motion. The first method evolves corrections to general relativity order by order in a perturbative expansion, while the second method introduces extra dynamical fields in such a way that strong hyperbolicity is recovered. We use shift-symmetric Einstein-scalar-Gauss-Bonnet gravity as a benchmark theory to illustrate the differences between these methods for several spacetimes of physical interest. We study the formation of scalar hair about initially nonspinning black holes, the collision of black holes with scalar charge, and the inspiral and merger of binary black holes. By directly comparing predictions, we assess the extent to which those from the approximate treatments can be meaningfully confronted with gravitational wave observations. We find that the order-by-order approach cannot faithfully track the solutions when the corrections to general relativity are non-negligible. The second approach, however, can provide consistent solutions, provided the timescale over which the dynamical fields are driven to their target values is made short compared to the physical timescales.

Published by the American Physical Society
2024
Influence of scalar field in massive particle motion in JNW spacetime
Authors: Turimov Bobur , Davlataliev Akbar , Abdujabbarov Ahmadjon , Ahmedov Bobomurat
Published: October 2024

In this paper, we investigated the motion of massive particles in the presence of scalar and gravitational fields, particularly focusing on the Janis-Newman-Winicour (JNW) naked singularity solution. It is shown that the innermost stable circular orbit radius strongly depends on scalar coupling parameter. Additionally, we explored the radiation reaction effects on particle dynamics, incorporating a reaction term into the motion equations. Numerical simulations indicated minimal impact on particle trajectories from radiation reaction. We also examined the oscillatory motion of particles around compact objects in the JNW spacetime, focusing on radial and vertical oscillations. Our analysis indicated that the scalar field’s coupling parameter and the spacetime deformation parameter n significantly alter the fundamental frequencies of these oscillations. Furthermore, we studied quasiperiodic oscillations (QPOs) in x-ray binaries, using the relativistic precession model to analyze upper- and lower-frequency relationships. Our results indicated that increasing parameters (n and gs) shifts the frequency ratio of 3∶2 QPOs closer to the naked singularity, with n decreasing and gs increasing both frequencies. Finally, we analyzed QPO data from four selected x-ray binary systems using Markov chain Monte Carlo analysis to constrain JNW parameters. Our findings provided insights into the mass, coupling, and deformation parameter for each system, enhancing our understanding of compact object dynamics in strong gravitational fields.

Published by the American Physical Society
2024
Doubly Optimal Parallel Wire Cutting without Ancilla Qubits
Authors: Harada Hiroyuki , Wada Kaito , Yamamoto Naoki
Published: October 2024

A restriction in the quality and quantity of available qubits presents a substantial obstacle to the application of near-term and early fault-tolerant quantum computers in practical tasks. To confront this challenge, some techniques for effectively augmenting the system size through classical processing have been proposed; one promising approach is quantum circuit cutting. The main idea of quantum circuit cutting is to decompose an original circuit into smaller subcircuits and combine outputs from these subcircuits to recover the original output. Although this approach enables us to simulate larger quantum circuits beyond physically available circuits, it needs classical overheads quantified by two metrics: the sampling overhead in the number of measurements to reconstruct the original output, and the number of channels in the decomposition. Thus, it is crucial to devise a decomposition method that minimizes both of these metrics, thereby reducing the overall execution time. This paper studies the problem of decomposing the n-qubit identity channel, i.e., n-parallel wire cutting, into a set of local operations and classical communication; then we give an optimal wire-cutting method composed of channels based on mutually unbiased bases that achieves minimal overheads in both the sampling overhead and the number of channels, without ancilla qubits. This is in stark contrast to the existing method that achieves the optimal sampling overhead yet with ancilla qubits. Moreover, we derive a tight lower bound on the number of channels in parallel wire cutting without ancilla systems and show that only our method achieves this lower bound among the existing methods. Notably, our method shows an exponential improvement in the number of channels, compared to the aforementioned ancilla-assisted method that achieves optimal sampling overhead. Our work significantly alleviates the additional overheads for the wire-cutting method and may provide essential components for the early success of quantum computing.

Published by the American Physical Society
2024
Dynamics behaviours of N-kink solitons in conformable Fisher–Kolmogorov–Petrovskii–Piskunov equation
Authors: Ullah Ikram
Published: October 2024

Purpose

This manuscript is related to compute $N$-kink soliton solutions for conformable Fisher–Kolmogorov equation (CFKE) by using the generalized extended direct algebraic method (EDAM). The considered problem has important applications in mathematical biology and reaction diffusion processes. Also, the mentioned problem has significant applications in population dynamics. The fractional order conformable derivative has many features as compared to the other fractional order differential operators. For instance, the chain, product and quotient procedures do not satisfy by other fractional differential operators, but conformable operators obey the mentioned rules. Hence, we compute the soliton solutions for the mentioned problem and present its various dynamical behaviours graphically.

Design/methodology/approach

The generalized EDAM is used in this article to examine the calculation of N-kink soliton solutions for the CFKE. In mathematical biology and reaction-diffusion processes, the topic under consideration holds great significance, especially when considering population dynamics.

Findings

The results highlight the benefits of utilising conformable derivatives in mathematical modelling and further our understanding of fractional differential equations and their applications.

Research limitations/implications

The work focuses primarily on N-kink soliton solutions, which may limit the examination of alternative types of solutions (e.g., multi-soliton or periodic solutions) that might give new insights into the dynamics of the CFKE.

Practical implications

The generated N N-kink soliton solutions can enhance mathematical models in biological contexts, notably in modelling population dynamics, disease propagation and ecological interactions, leading to better forecasts and interventions.

Social implications

Public health initiatives can benefit from the understanding of disease transmission and intervention efficacy that comes from modelling population dynamics and reaction-diffusion processes.

Originality/value

The use of the generalized EDAM to obtain solutions for N-kink soliton problems is an innovative method for solving the conformable Fisher–Kolmogorov equation, demonstrating the power of this mathematical tool.
A new lens into workplace equity: the equity of employment systems
Authors: Lai Patrick Ho Lam , Hogan Deborah , McNamara Tay , Pitt-Catsouphes Marcie , Christensen Kathleen , Bradley Samuel L.
Published: October 2024

Purpose

The unprecedented exigencies of COVID-19 and the subsequent spotlight on systemic racial, social and economic disparities have brought workplace equity to the forefront of organizational dialogue. These discontinuities set the stage for discussions about possible limitations of traditional diversity, equity and inclusion (DEI) approaches that may have overlooked disparities in specific organizational systems. In response, we conducted an exploratory study to examine a new framework that focuses attention on the equity of employment systems that contextualize employees’ experiences of equity at the workplace.

Design/methodology/approach

This paper introduces a framework that focuses on the equity of ten key employment systems (job structures, compensation and benefits, recruitment and hiring, orientation and onboarding, supervision and mentoring, training and career development, employee performance assessment and feedback, employee resources and supports, promotion and separation). Combining the indices that measured the equity of these ten employment systems, we created an Overall Equity of Employment Systems Index and examined antecedent variables and outcomes related to the index. Data were gathered from HR leaders of 1,062 workplaces in the US.

Findings

Utilizing multivariate analyses, this research found that lower scores on the Organizational Pressures Index were consistently linked to higher levels of equity across all of the employment systems. Furthermore, higher percentages of women and employees of color were positively associated with increased equity in most of the employment systems and in the Overall Equity of Employment System Index. There was a significant positive relationship between the Overall Equity of Employment Systems Index and organizational resilience, while a negative relationship was observed with employee stress.

Practical implications

This study extends the existing DEI literature by offering a new framework that employers can use to: (1) assess the equity of specific employment systems and (2) strengthen the equity components of the employment systems.

Originality/value

The framework used for this exploratory study offers an alternative approach to the study of systemic equity in the workplace.
Coordination mechanisms applied to logistical systems for local disaster preparedness: a Latin American case
Authors: López-Vargas Juan Camilo , Meisel José D. , Cárdenas-Aguirre Diana María , Medina Pablo
Published: October 2024

Purpose

The study aims to present an agent-based simulation model (ABM) for exploring interorganizational coordination scenarios in local disaster preparedness. This approach includes local actors and logistical processes as agents to compare various strategic coordination mechanisms.

Design/methodology/approach

The ABM model, developed in the Latin American context, specifically focuses on a case study of Colombia. Three coordination mechanisms (centralized, decentralized and cluster-type) have been evaluated using three performance indicators: effectiveness, efficiency and flexibility.

Findings

Simulation results show that the decentralized scenario outperforms in terms of efficiency and flexibility. On the contrary, the centralized and cluster-type scenarios demonstrate higher effectiveness, achieving a greater percentage of requirements coverage during the disaster preparedness stage. The ABM approach effectively evaluates strategical coordination mechanisms based on the analyzed performance indicators.

Research limitations/implications

This study has limitations due to the application of results to a single real case. In addition, the focus of the study is primarily on a specific type of disaster, specifically hydrometeorological events such as flash floods, torrential rains and landslides. Moreover, the scope of decision-making is restricted to key actors involved in local-level disaster management within a municipality.

Originality/value

The proposed ABM model has the potential as a decision-making tool for policies and local coordination schemes for future disasters. The simulation tool could also explore diverse geographical scenarios and disaster types, demonstrating its versatility and broader applicability for further insights and recommendations.
How broadband internet shapes household tourism decisions: a double/debiased machine learning-based difference-in-difference approach
Authors: Jia Haowen
Published: October 2024

Purpose

This study aims to examine the influence of broadband internet on Chinese households’ tourism decisions and spending patterns. It reveals the transformative potential of digital connectivity in enhancing tourism activity.

Design/methodology/approach

Using a rigorous double/debiased machine learning-based difference-in-difference (DMLDiD) method and extensive panel data, this research quantitatively analyzes the impact of broadband on household tourism engagement and financial allocations. It incorporates comprehensive robustness checks, including placebo tests and algorithm variations, to ensure the validity of the findings.

Findings

Within households with broadband access, the results indicate a significant increase of 3.54% and 31.24% in tourism participation and tourism-related expenditures, respectively. This study attributes these outcomes to enhanced household incomes, facilitated online transactions and alleviated credit constraints, highlighting notable disparities in impact across urban versus rural settings and among distinct demographic categories. Additionally, the moderating effects of marital status and household size reveal that married households and a greater number of members tend to leverage broadband access more effectively for making tourism-related decisions and expenditures.

Originality/value

By pioneering the application of the DMLDiD approach to examine household financial behaviors toward tourism, this study contributes novel insights to the economic discourse on the role of digital infrastructure in tourism development. It offers empirical evidence and strategic implications for policymakers and industry professionals who seek to leverage digital connectivity to enhance tourism.
Navigating hospitality innovation (1995–2023): a bibliometric review and forward outlook
Authors: Peng Xuerong , Zhang Lian , Lee Seoki , Song Wenhao , Shou Keyan
Published: October 2024

Purpose

This study aims to identify key contributors, research themes, research gaps, and future directions in hospitality innovation by conducting bibliometric and content analyses of peer-reviewed articles in this field.

Design/methodology/approach

A bibliometric analysis was conducted using VOSviewer software on 2,698 peer-reviewed English-language articles retrieved from the Web of Science database, published between 1995 and 2023. Key contributors were identified based on publication volume, citation, and co-citation analysis. Co-occurrence analysis of index keywords and content analysis of influential articles were used to identify research themes.

Findings

The study identified four distinct research themes in hospitality innovation: (1) digital technology adoption primarily among customers, (2) innovation management within hospitality firms, focusing on knowledge management and eco-innovation, (3) service innovation primarily among employees, and (4) business model innovation involving multiple stakeholders. Additionally, the study determined key contributors, highlighted research gaps, and provided suggestions for future research directions.

Originality/value

This study contributes to the existing literature by providing a systematic and in-depth review of hospitality innovation research. It identifies key contributors, research themes, and potential gaps for future research, offering valuable insights for both industry practitioners and scholars.
Islamic locus of control concept and its implications on individual behavior in organizations
Authors: Zakiy Muhammad , Santoso Claudius Budi , Rosari Reni , Tjahjono Heru Kurnianto
Published: October 2024

Purpose

This paper aims to introduce the concept of Islamic locus of control (ILoC) and explores its influence on individual behavior within organizational contexts. It aims to integrate Islamic values into the traditional understanding of LoC and investigate how ILoC affects motivation, responsibility and resilience among Muslim individuals in the workplace.

Design/methodology/approach

Using a conceptual approach, this paper draws from Islamic sources such as the Qur’an and Hadith, as well as literature on psychology, human resource management and Islamic theology. It synthesizes relevant theories and concepts to develop a comprehensive understanding of ILoC and its significance in organizational settings.

Findings

ILoC encompasses key dimensions including ikhtiyar (effort), tawakkul (reliance on Allah) and qadr (Divine Decree), which shape individuals’ perceptions of control and action within organizations. Individuals with a high ILoC are expected to exhibit greater motivation, responsibility and resilience, while also maintaining acceptance of Allah’s decree.

Research limitations/implications

Future research should focus on developing valid measurement instruments for assessing ILoC and conducting empirical studies to test its impact on organizational outcomes.

Practical implications

Understanding and fostering a supportive environment for individuals with a high ILoC can enhance motivation, responsibility and overall productivity within Islamic organizations.

Social implications

Promoting an environment that respects and integrates religious beliefs can contribute to social cohesion and harmony within diverse organizational settings.

Originality/value

This paper contributes to the existing literature by introducing the novel concept of ILoC and offering insights into its implications for organizational behavior within Islamic contexts. It bridges the gap between psychology, human resource management and Islamic theology, providing a unique perspective on how religious beliefs influence individual behavior in the workplace.
When library cares: mining insights from LibQUAL+ to determine university students’ priorities
Authors: Zulfiqar Ayisha , Khalid Ayesha
Published: October 2024

Purpose

This study aims to evaluate students' satisfaction with university library services in southern Punjab, Pakistan, emphasizing their perspective on service quality (SQ).

Design/methodology/approach

A LibQUAL+® survey with 22 core items was conducted within university settings using convenience sampling. In total, 345 usable responses were returned through Google Forms. Data analysis involved descriptive statistics, ordinal logistic regression test, Pearson and Deviance statistics and chi-square test to assess the satisfaction status of library users.

Findings

The study found that libraries generally meet SQ standards. However, there were minor gaps in information control (IC) and library as place (LP).

Practical implications

The study provides library administrators with actionable insights to enhance services, encouraging stakeholders to adopt optimal library practices for heightened efficiency and user satisfaction.

Social implications

It highlights the crucial role of libraries in shaping future societal progress by emphasizing the need for elevated user services. Librarians can use this knowledge to modify their planning and take impactful initiatives that align with the evolving needs of their users.

Originality/value

While many studies have utilized LibQUAL, this research is unique for its focus on addressing university library services in underdeveloped regions facing economic challenges. It attempts to fill the information gap by offering a transferable approach for strategic priorities in similar settings.
Economics and financial sustainability in microfinancing: do investment flows toward developing countries, rural areas, microenterprises and female borrowers foster institutionalization?
Authors: Singh Kuldeep
Published: October 2024

Purpose

The long-term sustainability of microfinancing institutions (MFIs) is essential for poverty reduction. This study aims to empirically evaluate whether contemporary microfinance economics supports the institutionalization of MFIs, which are crucial for the socioeconomic development of marginalized communities.

Design/methodology/approach

This research examines the flow of funds from wealthy economic areas (high-income countries, richer urban areas and capital-rich corporations) to poorer regions (low-income countries, poorer rural areas, female borrowers and financially constrained microenterprises) as a proxy for microfinance economics. Financial sustainability and institutionalization are assessed through return on assets and operational self-sufficiency. The study also considers credit risk as a key independent variable. Using panel data analysis of 333 MFIs from the USA and India, covering 2008–2018, sourced from the Microfinance Information Exchange data set on the World Bank website, this paper analyzes these dynamics.

Findings

Results show that credit risks negatively affect the financial sustainability of MFIs in both developed and developing countries. Contrary to expectations, the development status of a nation positively moderates the impact of credit risks on financial sustainability. In developing countries, intra-nation investments do not yield additional returns for MFIs or interact with credit risks. However, the economics of microfinance support the institutionalization of MFIs in these regions.

Originality/value

This study provides valuable empirical evidence on the relationship between microfinance economics and institutionalization, addressing a critical need in the microfinancing sector.
Underwater unexploded ordnance discrimination based on intrinsic target polarizabilities – A case study
Authors: Gasperikova Erika , Conti Ugo , Morrison H. Frank
Published: October 2024

Seabed unexploded ordnance that resulted partly from the high failure rate among munitions from more than 80 years ago and from decades of military training and testing of weapons systems poses an increasing concern all around the world. Although existing magnetic systems can detect clusters of debris, they are not able to tell whether a munition is still intact requiring special removal (e.g. in situ detonation) or is harmless scrap metal. The marine environment poses unique challenges, and transferring knowledge and approaches from land to a marine environment has not been easy and straightforward. On land, the background soil conductivity is much lower than the conductivity of the unexploded ordnance and the electromagnetic response of a target is essentially the same as that in free space. For those frequencies required for target characterization in the marine environment, the seawater response must be accounted for and removed from the measurements. The system developed for this study uses fields from three orthogonal transmitters to illuminate the target and four three‐component receivers to measure the signal arranged in a configuration that inherently cancels the system's response due to the enclosing seawater, the sea–bottom interface and the air–sea interface for shallow deployments. The system was tested as a cued system on land and underwater in San Francisco Bay – it was mounted on a simple platform on top of a support structure that extended 1 m below and allowed the diver to place metal objects to a specific location even in low‐visibility conditions. The measurements were stable and repeatable. Furthermore, target responses estimated from marine measurements matched those from land acquisition, confirming that the seawater and air–sea interface responses were removed successfully. Thirty‐six channels of normalized induction responses were used for the classification, which was done by estimating the target principal dipole polarizabilities. Our results demonstrated that the system can resolve the intrinsic polarizabilities of the target, with clear distinctions between those of symmetric intact unexploded ordnance and irregular scrap metal. The prototype system was able to classify an object based on its size, shape and metal content and correctly estimate its location and orientation.
Three‐dimensional vegetation structure drives patterns of seed dispersal by African hornbills
Authors: Russo Nicholas J. , Nshom Docas L. , Ferraz António , Barbier Nicolas , Wikelski Martin , Noonan Michael J. , Ordway Elsa M. , Saatchi Sassan , Smith Thomas B.
Published: October 2024

Three‐dimensional (3D) vegetation structure influences animal movements and, consequently, ecosystem functions. Animals disperse the seeds of 60%–90% of trees in tropical rainforests, which are among the most structurally complex ecosystems on Earth.

Here, we investigated how 3D rainforest structure influences the movements of large, frugivorous birds and resulting spatial patterns of seed dispersal.

We GPS‐tracked white‐thighed (Bycanistes albotibialis) and black‐casqued hornbills (Ceratogymna atrata) in a study area surveyed by light detection and ranging (LiDAR) in southern Cameroon.

We found that both species preferred areas of greater canopy height and white‐thighed hornbill preferred areas of greater vertical complexity. In addition, 33% of the hornbills preferred areas close to canopy gaps, while 16.7% and 27.8% avoided large and small gaps, respectively. White‐thighed hornbills avoided swamp habitats, while black‐casqued increased their preference for swamps during the hottest temperatures. We mapped spatial probabilities of seed dispersal by hornbills, showing that 3D structural attributes shape this ecological process by influencing hornbill behaviour.

These results provide evidence of a possible feedback loop between rainforest vegetation structure and seed dispersal by animals. Interactions between seed dispersers and vegetation structure described here are essential for understanding ecosystem functions in tropical rainforests and critical for predicting how rainforests respond to anthropogenic impacts.
The impacts of New York's balance billing regulation on ground ambulance pricing
Authors: Xu Wendy Y. , Garmon Christopher , Retchin Sheldon M. , Li Yiting
Published: October 2024

Objective

To examine the effects of New York's surprise billing regulations on price changes by emergency ground ambulance service providers.

Study Design

We exploited a natural experiment using a difference‐in‐differences design with randomization inference (RI) to examine the effects of New York state regulations on the prices of emergency ground ambulances, analyzing 2012–2019 commercial claims data. In March 2015, New York implemented a law protecting patients from surprise out‐of‐network (OON) balance bills, including ground ambulance services. New York's policy tied OON ground ambulance reimbursements to usual, customary, and reasonable rates that typically reflect charges. The control group consisted of similar states that never enacted surprise billing laws. Although self‐funded plans are exempted from state laws, we also examined for spillover effects on self‐funded plans.

Data Source and Analytic Sample

Multi‐payer national commercial plan claims data were used. The study sample was selected by isolating claims involving an emergency ground ambulance activation code.

Principal Findings

The event study findings indicated that New York's law led to a continuous increase in prices, relative to controls. The law's implementation was associated with an overall emergency ground ambulance price increase of 13 percentage points (RI p‐value: 0.07). We observed a 21‐percentage‐point increase in in‐network prices (RI p‐value: 0.07) and a 19‐percentage‐point increase in OON prices (RI p‐value: 0.07), relative to controls, for fully insured health plans. Similar changes in overall prices and in in‐network prices were observed in self‐insured plans. Last, our study did not find statistically significant evidence of changes in out‐of‐pocket cost‐sharing amounts under New York's regulation.

Conclusions

Balance billing laws based on charges can lead to price increases for emergency ground ambulance services. Legislation intended to inoculate patients from these surprise billings for ground ambulance transportation may have unintended consequences for costs of care.

What is known on this topic

Emergency ground ambulances are a major source of surprise billing.

The federal No Surprises Act of 2020 excluded emergency ground ambulance services.

Some states have regulations that prohibit out‐of‐network balance bills for ground ambulance services.

What this study adds

The study provides the first empirical evidence on the potential impacts of regulations on price changes among emergency ground ambulance providers.

The study offers evidence of state policies' effects on fully insured plans and potential spillover effects on self‐funded plans.

Experiences from New York's state ambulance out‐of‐network billing regulation indicate that tying reimbursement policies to charges may have the unintended consequences of increasing health care costs.
Impact of delayed seed drop on rodent‐mediated seed dispersal and predation of pine
Authors: LAI Yuling , DOU Haojun , ZHOU Yuqun , WANG Zhenyu , HOU Ling , CAO Lin
Published: October 2024

Many plants exhibit a canopy seed bank, where seeds persist within the canopy for prolonged periods, gradually descending over time and potentially influencing seed predation and animal‐mediated dispersal. However, the impact of delayed seed drop on animal predation and seed dispersal remains unclear. We used Chinese Armand pine seeds to simulate delayed seed drop of the canopy seed bank by releasing 7800 pine seeds in both winter and the following summer over 2 years, tracking their fates to investigate its effect on seed predation and dispersal by rodents in a pine plantation in southwest China. Results showed significant seasonal differences in seed fate. In summer, seeds experienced higher predation rates (62.08% vs 3.80% in winter) and lower scatter‐hoarding rates (4.18% vs 15.40% in winter). Additionally, seeds in summer were dispersed farther (4.20 m vs. 3.56 m in winter) and primarily formed single‐seed caches, as opposed to multi‐seed caches in winter. Although delayed seed drop increased immediate predation risks, favorable summer conditions allowed for rapid germination, reducing long‐term exposure to predation. In conclusion, while delayed seed drop increases immediate predation risks and reduces caching, it concurrently enhances dispersal distances and reduces cache size.
Thermal evaluation of solar dryers and the effect on the antioxidant and some physicochemical properties of Agastache mexicana and Rosmarinus officinalis
Authors: Domínguez‐Niño Alfredo , Lucho‐Gómez Ana María , Chávez‐Santos Rosa María , Martínez Roberto , Guillén‐Velázquez Paulina , Castillo‐Téllez Beatriz , García‐Valladares Octavio
Published: October 2024

Lemon balm (Agastache mexicana) and rosemary (Rosmarinus officinalis) were dried using a mixed‐mode solar dryer. A 23‐factorial design was carried out: operation mode (mesh shade and direct irradiance), airflow (natural convection and forced convection), and type of flat plate solar collector cover (polycarbonate and glass). The drying kinetics of lemon balm and rosemary ranged from 4.5 to 6.5 h and 4 to 7 h, respectively, according to the operation mode of the solar dryer. The highest percentage of antioxidant activity in the 2,2‐diphenyl‐1‐picrylhydrazil tests was lemon balm, with values between 88% and 93% (100 µg/mL), and rosemary, 88% and 92% (100 µg/mL). When forced convection was applied, solar collector thermal efficiency increased from 3.97%–5.11% to 17.20%–24.75%, dryer efficiencies ranged from 4.78% to 6.05%, and drying efficiencies between 14.17% and 44.23%. The lowest color difference (6.01) for lemon balm was shown with the mesh shade, forced convection, and glass cover collector, and for rosemary, the lowest color difference (12.87) resulted from using the mesh shade and natural convection; according to the analysis of variance, the cover collector did not affect significantly the color difference. Dehydrated lemon balm and rosemary could be used as an additive for medicinal, gastronomic, and food preservative applications.

Practical Application

The results are significant for designing dryers for community centers in areas where the production and losses of fruits, vegetables, aromatic herbs, and edible flowers are high. The novelty of this research is to introduce a new product for the consumer; in this case, the traditional dried rosemary and lemon balm in powder form as a nutritional source, both for the preparation of remedies and for direct consumption in dishes, powders, or healthy pills and food supplements.
Optimising PTV margins in oesophageal cancer radiotherapy: A modern radiotherapy planning, treatment delivery and verification approach – A single institutional analysis
Authors: Mitchell Jack , Campbell Amelia , Zhao Ming , Harvey Jennifer , Mai Gang Tao , Lee Yoo Young
Published: October 2024

Introduction

Radiotherapy plays a key role in the multidisciplinary management of oesophageal cancers across neoadjuvant, definitive and palliative settings. Improved precision in radiotherapy planning and delivery techniques have allowed treating disease with tighter margins reducing toxicity. In this study, we examine the appropriateness of current practice in defining the planning target volume (PTV).

Methods

This is a single institutional retrospective study of patients who received radiotherapy for oesophageal cancers using volumetric modulated arc therapy (VMAT) during 2020. All cone‐beam computerised tomography (CBCT) scans were reviewed to assess whether PTV expansions appropriately accounted for tumour motion and interfractional variation.

Results

Of the 27 patients, 2 (7%), 5 (19%) and 20 (74%) had cervical, thoracic and distal/gastro‐oesophageal junction (GOJ) disease, respectively. 16 (59%) had adenocarcinoma and 9 (33%) had squamous cell carcinoma. 9 of 20 distal/GOJ patients were planned and treated according to the institutional stomach filling protocol. 521/528 (98.7%) CBCTs demonstrated adequate target coverage. Cervical, thoracic and GOJ regions demonstrated adequate target coverage in 57/58, 96/97 and 368/373 CBCTs with median PTV expansions of 5, 7 and 7 mm, respectively. In four patients with GOJ disease, CBCT review identified five episodes where the target volume was insufficiently covered during the treatment course.

Conclusion

In this single institutional retrospective study, for the vast majority of patients, our institutional practice of defining PTV margins achieved satisfactory target treatment. The interfractional variations observed in patients with GOJ tumours due to target motion and variable gastric volume, highlights the role of further refinements to motion management techniques in this cohort.
Angiopoietin‐2 reverses endothelial cell dysfunction in progeria vasculature
Authors: Vakili Sahar , Izydore Elizabeth K. , Losert Leonhard , Cabral Wayne A. , Tavarez Urraca L. , Shores Kevin , Xue Huijing , Erdos Michael R. , Truskey George A. , Collins Francis S. , Cao Kan
Published: October 2024

Abstract

Hutchinson‐Gilford progeria syndrome (HGPS) is a rare premature aging disorder in children caused by a point mutation in the lamin A gene, resulting in a toxic form of lamin A called progerin. Accelerated atherosclerosis leading to heart attack and stroke are the major causes of death in these patients. Endothelial cell (EC) dysfunction contributes to the pathogenesis of HGPS related cardiovascular diseases (CVD). Endothelial cell–cell communications are important in the development of the vasculature, and their disruptions contribute to cardiovascular pathology. However, it is unclear how progerin interferes with such communications that lead to vascular dysfunction. An antibody array screening of healthy and HGPS patient EC secretomes identified Angiopoietin‐2 (Ang2) as a down‐regulated signaling molecule in HGPS ECs. A similar down‐regulation of Ang2 mRNA and protein was detected in the aortas from an HGPS mouse model. Addition of Ang2 to HGPS ECs rescues vasculogenesis, normalizes endothelial cell migration and gene expression, and restores nitric oxide bioavailability through eNOS activation. Furthermore, Ang2 addition reverses unfavorable paracrine effects of HGPS ECs on vascular smooth muscle cells. Lastly, by utilizing adenine base editor (ABE)‐corrected HGPS ECs and progerin‐expressing HUVECs, we demonstrated a negative correlation between progerin and Ang2 expression. Lastly, our results indicated that Ang2 exerts its beneficial effect in ECs through Tie2 receptor binding, activating an Akt‐mediated pathway. Together, these results provide molecular insights into EC dysfunction in HGPS and suggest that Ang2 treatment has potential therapeutic effects in HGPS‐related CVD.
Trajectories following Impella 5.5 support are associated with initial presentation acuity
Authors: Maigrot Jean‐Luc A. , Starling Randall C. , Soltesz Edward G. , Smedira Nicholas G. , Tong Michael Z. Y. , Unai Shinya , Bhat Pavan , Moros David , Blackstone Eugene H. , Weiss Aaron J.
Published: October 2024

Background

Impella 5.5 is a temporary left ventricular assist device utilized to support patients with cardiogenic shock and those undergoing high‐risk cardiac interventions.

Methods

From October 2019 to January 2023, 226 patients received Impella 5.5 support at Cleveland Clinic main campus. Patients were stratified by Society for Cardiovascular Angiography and Interventions (SCAI) shock stages. Immediate post‐Impella 5.5 trajectories were compared across groups. Trajectories were defined as mortality on Impella 5.5, transition to advanced heart failure therapies (durable left ventricular assist device/heart transplantation), or survival to Impella 5.5 removal without advanced therapies.

Results

Overall, 148 (65%) patients with cardiogenic shock and 78 (35%) undergoing high‐risk cardiac interventions received Impella 5.5 support. SCAI stage was A in 63 (28%), B in 10 (4.4%), C in 29 (13%), D in 104 (46%), and E in 20 (8.8%). Mortality on Impella 5.5 was highest in SCAI stage E (A: 3.2%, B: 10%, C: 14%, D: 27%, E: 35%; p < 0.01). Transition to advanced therapies (durable left ventricular assist device or heart transplantation) was highest in SCAI stages C‐D (A: 1.6%, B: 0.0%, C: 45%, D: 36%, E: 20%; p < 0.01). Survival to Impella removal without advanced therapies was highest in SCAI stages A‐B (A: 95%, B: 90%, C: 41%, D: 38%, E: 45%; p < 0.01).

Conclusions

Stratification by presentation acuity in candidates for Impella 5.5 insertion may help identify which patients may and may not benefit from this escalation of tailored temporary mechanical circulatory support.
Imprint of preterm birth with very low birth weight on optic disc OCT in adulthood—A two‐country birth cohort study
Authors: Kulmala Maarit K. , Jørgensen Anna , Austeng Dordi , Evensen Kari Anne I. , Kajantie Eero , Morken Tora Sund , Majander Anna
Published: October 2024

Purpose

To determine the pattern, degree and prevalence of optic disc optical coherence tomography (OCT) alterations in adults born preterm with very low birth weight (VLBW; birth weight < 1500 g).

Methods

Optic disc OCT was assessed in 98 VLBW participants and 139 term‐born controls from birth cohorts in Finland and Norway at the mean age of 36 years. The participants had not been treated for retinopathy of prematurity and had no diagnosed brain abnormality. OCT assessment included parameters for optic disc size, neural rim and peripapillary retinal nerve fibre layer thickness (pRNFLT), and for the foveal developmental stage. Background data, visual acuity, refractive error and intraocular pressure were recorded.

Results

In the VLBW group, optic disc neural rim and pRNFLT were significantly decreased, most frequently in the nasal and inferior sectors. In 40% (95% CI: 33–47) of the VLBW eyes, nerve fibre thickness of at least one optic disc sector was below the fifth percentile of the control group, including 9% (95% CI: 6–14) subgroup falling below the first percentile, that is, clinically below normal limits. VLBW participants with nerve fibre thickness below the fifth percentile did not differ by perinatal data or foveal developmental stage from the other VLBW participants. All participants had normal visual acuity.

Conclusion

A moderate decrease of the optic disc neural rim and pRNFLT is frequently seen in clinically healthy adults born preterm with VLBW. Awareness of the VLBW‐related optic disc nerve fibre shallowness especially in the inferior and nasal sectors is important while evaluating acquired optic disc pathology in adulthood.
Development and validation of the Abolitionist Ideology Scale with abolitionist‐identifying and nationally representative samples
Authors: Oswald Flora , Pham Minh Duc , Chaney Kimberly E.
Published: October 2024

Building upon recent calls for the integration of abolition into psychology, we develop and validate a measure of Abolitionist Ideology. In two studies with abolitionist leaning (N = 201, abolitionist‐identifying n = 58) and nationally representative (N = 350) samples, we identify and confirm a three‐factor, 26‐item measure including subscales of Alternatives to State Violence, Revolutionary Abolitionism, and Abolitionist Identity. The Abolitionist Ideology Scale demonstrates convergent validity with measures including support for Black Lives Matter, critical consciousness, openness to experience, radical imagination, and attribution of violence to the state. The scale demonstrates divergent validity from measures including social dominance orientation (SDO) and political conservatism. Finally, the scale predicted activism tenacity above and beyond a related measure of carceral system justification. The Abolitionist Ideology Scale demonstrates initial reliability and validity and will be useful for those aiming to engage abolition in liberatory theory, research, and practice.
Enhancing AR‐based learning environments for STEM education: A design‐based study on design features, kinematics learning and mathematics self‐efficacy
Authors: Li Shuhui , Jiao Xinyue , Cai Su , Shen Yihua
Published: October 2024

This design‐based research project explored how various design features of AR‐based learning environments (ARLE) influence students' mathematics self‐efficacy and learning of kinematics. Specifically, five ARLEs with different design features were developed and implemented with 136 seventh‐grade students in two rounds. Data were gathered from pre‐ and post‐mathematics self‐efficacy tests, interviews, classroom observation records and reflective journals, to identify which design features promote or hinder students' learning and self‐efficacy. Results revealed that adopting a well‐designed ARLE is a viable way to promote students' learning and mathematics self‐efficacy, and the success of ARLE lies in (1) coherent tasks with proper time for self‐exploration, progressive levels, useful problem contexts and a certain degree of open‐endedness, and (2) sufficient technological affordances with strengthened authenticity, clarity and integrated media presentation, as well as engaging interactions with decent flexibility, embodied actions and feedback. These results validated the applicability of the proposed checklist for ARLE designers and practitioners in their design and implementation of ARLEs, within the domain of mathematics, physics and beyond.

Practitioner notes

What is already known about this topic

AR‐based learning environments (ARLEs) have demonstrated substantial advantages in STEM education, but ARLEs can be a drawback if they are not adequately designed.

ARLE may facilitate students' mathematics self‐efficacy, and relevant design features are underexplored.

Design‐based research sustains interventions combining empirical research and theory‐driven design of innovative learning environments, for example, ARLEs.

What this paper adds

Demonstrates the potential of ARLEs that can be used in classrooms to support STEM learning.

Identifies a collection of effective and ineffective design features of ARLEs that promote or hinder students' STEM learning and mathematics self‐efficacy.

Tackles the challenges for the design of ARLEs for classrooms by taking AR technological affordances and the pedagogical perspective together.

Implications for practice and/or policy

Five ARLEs for STEM topics were developed and implemented in secondary schools.

Evidence of positive impacts of ARLEs on students' learning and mathematics self‐efficacy.

Our research produces useful guidelines for designers and practitioners in their development and implementation of ARLEs in real classrooms.
Generating Flight Summaries Conforming to Cinematographic Principles
Authors: Lino Christophe , Cani Marie‐Paule
Published: October 2024

We propose an automatic method for generating flight summaries of prescribed duration, given any planed 3D trajectory of a flying object. The challenge is to select relevant time‐ellipses, while keeping and adequately framing the most interesting parts of the trajectory, and enforcing cinematographic rules between the selected shots. Our solution optimizes the visual quality of the output video both in terms of camera view and film editing choices, thanks to a new optimization technique, designed to jointly optimize the selection of the interesting parts of a flight, and the camera animation parameters over time. To our best knowledge, this solution is the first one to address camera control, film editing, and trajectory summarizing at once. Ablation studies demonstrate the visual quality of the flights summaries we generate compared to alternative methods.
Robust and Artefact‐Free Deformable Contact with Smooth Surface Representations
Authors: Du Y. , Li Y. , Coros S. , Thomaszewski B.
Published: October 2024

Modeling contact between deformable solids is a fundamental problem in computer animation, mechanical design, and robotics. Existing methods based on C0‐discretizations—piece‐wise linear or polynomial surfaces—suffer from discontinuities and irregularities in tangential contact forces, which can significantly affect simulation outcomes and even prevent convergence. In this work, we show that these limitations can be overcome with a smooth surface representation based on Implicit Moving Least Squares (IMLS). In particular, we propose a self collision detection scheme tailored to IMLS surfaces that enables robust and efficient handling of challenging self contacts. Through a series of test cases, we show that our approach offers advantages over existing methods in terms of accuracy and robustness for both forward and inverse problems.