bluuebunny/crossref_metadata_2025 huggingface dataset:
Practical Application of Digital Twins for Transportation Asset Data Management: Case Example of a Safety Hardware Asset
Authors: Ammar Ashtarout , Maier Francesca , Pratt William S. , Richard Elaine , Dadi Gabriel
Published: March 2024

Digital Twins have emerged as a transformative technology with immense potential for enhancing asset data management in various industries. The transportation industry relies heavily on properly functioning and maintaining safety hardware assets, such as crash barriers, guiderails, and road signs, among others, to ensure the safety of road users. However, traditional asset data management practices for ancillary assets often fall short of providing real-time, comprehensive insights into the condition and performance of these critical assets. Conversely, Digital Twins can analyze data for predictive and preventive maintenance using cutting-edge technologies. This will enable asset managers to proactively address potential safety concerns, plan maintenance schedules efficiently, and optimize resource allocation. This can be achieved by leveraging historical asset data and real-time condition updates and providing the Digital Twin with an information-rich analytical model. The key steps to creating an information-rich analytical model are identifying the asset data that should be collected, understanding data architecture throughout the asset lifecycle, and generating asset data governance and stewardship frameworks. As such, this paper investigates the current state of practice for ancillary asset data collection and management and investigates the generation of information-rich analytical models for guiderails, a critical roadway safety hardware. Moreover, this study demonstrates how Digital Twins can be integrated and affect the development of transportation asset management systems. The findings of this article emphasize the significance of adopting Digital Twins in transportation asset data management. The case example showcases a compelling roadmap for other transportation agencies to consider integrating digital twins into their asset management strategies.
Advancements in self-assembling peptides: Bridging gaps in 3D cell culture and electronic device fabrication
Authors: Jafari Azadeh
Published: March 2024

Self-assembling peptides (SAPs) show promise in creating synthetic microenvironments that regulate cellular function and tissue repair. Also, the precise π-π interactions and hydrogen bonding within self-assembled peptide structures enable the creation of quantum confined structures, leading to reduced band gaps and the emergence of semiconductor properties within the superstructures. This review emphasizes the need for standardized 3D cell culture methods and electronic devices based on SAPs for monitoring cell communication and controlling cell surface morphology. Additionally, the gap in understanding the relationship between SAP peptide sequences and nanostructures is highlighted, underscoring the importance of optimizing peptide deposition parameters, which affect charge transport and bioactivity due to varying morphologies. The potential of peptide nanofibers as extracellular matrix mimics and the introduction of the zone casting method for improved film deposition are discussed within this review, aiming to bridge knowledge gaps and offer insights into fields like tissue engineering and materials science, with the potential for groundbreaking applications at the interface of biology and materials engineering.
#MeToo and Sexual Violence Reporting in the National Crime Victimization Survey
Authors: Worthen Meredith G. F. , Schleifer Cyrus
Published: March 2024

The Me Too Movement has reshaped cultural awareness about sexual violence but little is known about how this shift may have coincided with changes in the reporting of sexual violence. The current study is the first to use the National Crime Victimization Survey to compare pre-#MeToo and post-#MeToo reports of sexual violence across three different blocks of time (Time 1: 2014–2015; Time 2: October 2017–September 2019; Time 3: October 2019–September 2021). Comparisons include prevalence rates of overall sexual violence, self-reports of sexual violence, official police reports of sexual violence, and situational characteristics of sexual violence (offender was a stranger, victim injury, victim services used). We also examine gender (women/men) and racial (White women/non-White women) differences in sexual violence reporting. Using formal comparisons, we find a significant increase in the rates of overall sexual violence as well as self-reports and stranger-offender reports of sexual violence between the pre- (Time 1) and the first post-#MeToo time point (Time 2). However, these increases are no longer evident in Time 3. In addition, the changes between the pre- (Time 1) and the first post-#MeToo time point (Time 2) are driven primarily by White women’s reporting of sexual violence, and we find no significant changes in the rates of sexual violence experienced by men nor non-White women during these time periods.
Preparation and properties of a bismaleimide resin modified with a propargyl compound for electron beam irradiation curing
Authors: Zhang Yuhao , Wang Linxiang , Yuan Qiaolong , Zheng Qing , Wan Liqiang , Huang Farong
Published: March 2024

N, N, N′, N′ -Tetrapropargyl- p, p′-diaminodiphenylmethane (TPDDM) is synthesized and used to blended with 4,4′-bismaleimide diphenylmethane (BDM) as propargyl compound in a molten state to obtain a TPDDM modified bismaleimide (BTP) resin. The BTP resins are cured under electron-beam (EB) irradiation as well as heat. The cure degree and reactions of BTP resins are studied. The thermal stability and mechanical properties of the cured BTP resins are further investigated. The results show that the BTP resins can be cured under EB irradiation and have over 82% degree of cure, which increases with the increase of EB irradiation dose. The cure reactions of EB-cured BTP resin are similar to that of heat-cured BTP resin. The temperature at 5% weight loss ( Td5) and mechanical properties of the cured BTP resins are close analogies between EB and heat cure processes although the cure degrees of EB-cured BTP resins are lower. The glass transition temperature ( Tg) and flexural modulus of the EB-cured BTP resin are higher than that of the heat-cured BTP resin. The Tg of the EB-cured BTP resin can reach over 385°C. The TPDDM-modified BDM is a candidate bismaleimide resin for the EB irradiation curing process in advanced manufacturing technology.
Elastohydrodynamic lubrication simulation analysis and experimental verification of different tandem reciprocating rod seal systems
Authors: Guo Fei , Xiang Chong , Wang Yanan , Huang Le , Tian Yu , Wang Yuming
Published: March 2024

Utilizing multiple seals in tandem is a prevalent technique employed to enhance the reliability of hydraulic sealing systems. In this paper, based on the elastohydrodynamic lubrication simulation of a single seal interface, a methodology for evaluating the performance of tandem reciprocating rod seal systems is established by manipulating the boundary conditions of the seals based on the principle of flow conservation. Through the simulation of two sealing systems, it is observed that inadequate lubricating oil occurs in the second sealing ring when the first sealing ring surpasses its sealing performance. Conversely, if the second sealing ring outperforms the first one, pressure will be generated between them. Additionally, a self-constructed experimental platform is utilized, and the results demonstrate simulation accuracy within an error margin of less than 15% when compared to the corresponding experimental measurements.
A matching-based machine learning approach to estimating optimal dynamic treatment regimes with time-to-event outcomes
Authors: Wang Xuechen , Lee Hyejung , Haaland Benjamin , Kerrigan Kathleen , Puri Sonam , Akerley Wallace , Shen Jincheng
Published: March 2024

Observational data (e.g. electronic health records) has become increasingly important in evidence-based research on dynamic treatment regimes, which tailor treatments over time to patients based on their characteristics and evolving clinical history. It is of great interest for clinicians and statisticians to identify an optimal dynamic treatment regime that can produce the best expected clinical outcome for each individual and thus maximize the treatment benefit over the population. Observational data impose various challenges for using statistical tools to estimate optimal dynamic treatment regimes. Notably, the task becomes more sophisticated when the clinical outcome of primary interest is time-to-event. Here, we propose a matching-based machine learning method to identify the optimal dynamic treatment regime with time-to-event outcomes subject to right-censoring using electronic health record data. In contrast to the established inverse probability weighting-based dynamic treatment regime methods, our proposed approach provides better protection against model misspecification and extreme weights in the context of treatment sequences, effectively addressing a prevalent challenge in the longitudinal analysis of electronic health record data. In simulations, the proposed method demonstrates robust performance across a range of scenarios. In addition, we illustrate the method with an application to estimate optimal dynamic treatment regimes for patients with advanced non-small cell lung cancer using a real-world, nationwide electronic health record database from Flatiron Health.
Interval estimation in three-class receiver operating characteristic analysis: A fairly general approach based on the empirical likelihood
Authors: To Duc-Khanh , Adimari Gianfranco , Chiogna Monica
Published: March 2024

The empirical likelihood is a powerful nonparametric tool, that emulates its parametric counterpart—the parametric likelihood—preserving many of its large-sample properties. This article tackles the problem of assessing the discriminatory power of three-class diagnostic tests from an empirical likelihood perspective. In particular, we concentrate on interval estimation in a three-class receiver operating characteristic analysis, where a variety of inferential tasks could be of interest. We present novel theoretical results and tailored techniques studied to efficiently solve some of such tasks. Extensive simulation experiments are provided in a supporting role, with our novel proposals compared to existing competitors, when possible. It emerges that our new proposals are extremely flexible, being able to compete with contestants and appearing suited to accommodating several distributions, such, for example, mixtures, for target populations. We illustrate the application of the novel proposals with a real data example. The article ends with a discussion and a presentation of some directions for future research.
Mechanical Unloading Promotes Osteoclastic Differentiation and Bone Resorption by Modulating the MSC Secretome to Favor Inflammation
Authors: Wang Wanyuji , Zheng Xueling , Wang Hehe , Zuo Bin , Chen Sisi , Li Jiao
Published: March 2024

Aging, space flight, and prolonged bed rest have all been linked to bone loss, and no effective treatments are clinically available at present. Here, with the rodent hindlimb unloading (HU) model, we report that the bone marrow (BM) microenvironment was significantly altered, with an increased number of myeloid cells and elevated inflammatory cytokines. In such inflammatory BM, the osteoclast-mediated bone resorption was greatly enhanced, leading to a shifted bone remodeling balance that ultimately ends up with disuse-induced osteoporosis. Using Piezo1 conditional knockout (KO) mice (Piezo1fl/fl;LepRCre), we proved that lack of mechanical stimuli on LepR+ mesenchymal stem cells (MSCs) is the main reason for the pathological BM inflammation. Mechanically, the secretome of MSCs was regulated by mechanical stimuli. Inadequate mechanical load leads to increased production of inflammatory cytokines, such as interleukin (IL)-1α, IL-6, macrophage colony-stimulating factor 1 (M-CSF-1), and so on, which promotes monocyte proliferation and osteoclastic differentiation. Interestingly, transplantation of 10% cyclic mechanical stretch (CMS)-treated MSCs into HU animals significantly alleviated the BM microenvironment and rebalanced bone remodeling. In summary, our research revealed a new mechanism underlying mechanical unloading-induced bone loss and suggested a novel stem cell-based therapy to potentially prevent disuse-induced osteoporosis.
Ultrasound Gel as a Source of Burkholderia cepacia Sepsis Outbreak in Preterm Neonates
Authors: Raj Raunak , Sujatha Radhika , Haneefa Sahira , Sundaresan Vishnu Vasantha , Rahul Aswathy
Published: March 2024

Background

In the middle of 2018, we noticed an outbreak of sepsis due to Burkholderia cepacia complex among inborn babies, and this continued till December 2020. These babies were not responding to conventional antibiotic therapy.

Aim

To study the clinical profile of neonates with Burkholderia septicemia, to determine its antimicrobial susceptibility patterns, and to identify the source of infection.

Materials and methods

This was a retrospective descriptive study conducted in the inborn nursery of the Government Medical College, Thiruvananthapuram for a period of 30 months, from June 2018 to December 2020. All babies whose blood culture was positive for Burkholderia were identified from the records. Microbiological surveillance was done for source identification.

Results

Out of the total 2264 neonates admitted during the study period, 84 (3.7%) had Burkholderia cepacia sepsis. The mean gestational age was 31(2) weeks. The most common clinical presentation was feed intolerance (64%) and 12% had a liver abscess. The highest antimicrobial sensitivity was observed for ceftazidime and cotrimoxazole (100%) followed by cefoperazone-sulbactam (98%) and meropenem (94%). The outbreak was controlled by the withdrawal of contaminated muti-use USG gel and the implementation of the practice of single-use sterile USG gel.

Conclusions

Gastrointestinal manifestations are predominantly a manifestation in Burkholderia cepacia sepsis and a strong suspicion of liver abscess should be kept in mind. cotrimoxazole and ceftazidime are the best choice of antibiotics. Unsterile ultrasound gel use in the labor room and NICU can be a source of infection
A New Formula for Estimating Insertion Length of Umbilical Catheters in Neonates: An Observational Study
Authors: Webb Jennifer , Elliott Sian , Watkins W. John , Stuttaford Laura , Banerjee Sujoy , Kayode-Adedeji Babatunde , Bagga Gautam , Sharma Neha , Chakraborty Mallinath
Published: March 2024

Objective

Current formulae used by clinicians to estimate the insertion length of umbilical catheters are inaccurate. We aimed to derive a new model that could improve accuracy in estimating the insertion length of umbilical catheters.

Study design

This was a multi-centre prospective observational study of neonates admitted to neonatal units and needing umbilical line(s) inserted for clinical reasons. Demographic data, catheter-related measurements and a new external length measurement—sternal notch to the umbilicus, were collected at three tertiary-level neonatal units in South Wales, UK. Generalised linear models were used to estimate the fit of the external length, birthweight, gestation and head circumference with catheter length and to derive a formula. The best fit was estimated by comparing r2 values for each equation.

Results

Data from 113 infants for each venous and arterial line were analysed for the new mathematical formulae. For both umbilical arterial catheterisation [[Formula: see text] and umbilical venous catheter (UVC) [[Formula: see text]], a quadratic model based on birthweight was found to have the best fit for predicting the insertion length of the catheters. However, the overall fit for UVCs was poorer for all explanatory variables ( y = estimated insertion length of the umbilical catheter in cm, x = birthweight in kg).

Conclusion

Our prospective multi-centre observational study identified a quadratic model based on birthweight as the best fit for estimating the insertion length of umbilical lines in neonates. This is a new finding and further development on earlier birthweight-based linear models.
Comparative Efficacy of Online vs. Face-to-Face Group Interventions: A Systematic Review
Authors: Rafieifar Maryam , Hanbidge Alice Schmidt , Lorenzini Sloan Bruan , Macgowan Mark J.
Published: March 2024

Purpose: Online group-based interventions are widely adopted, but their efficacy, when compared with similar face-to-face (F2F) psychosocial group interventions, has not been sufficiently examined. Methods: This systematic review included randomly controlled trials (RCTs) that compared an intervention/model delivered in both F2F and online formats. The review adhered to PRISMA guidelines and was registered with PROSPERO. Results: The search yielded 15 RCTs. Effect sizes ranged from small to exceptionally large. Between-condition effect sizes yielded nonsignificant differences in effectiveness except for three studies that reported superior effectiveness in outcomes for F2F interventions. High heterogeneity was found where only two studies integrated rigorous designs, thus limiting opportunity for a meta-analysis evaluation. Conclusions: Most studies showed comparable outcomes in both F2F and online modalities. However, given the heterogeneity of samples and outcomes, it is premature to conclude that online treatment is as effective as F2F for all challenges and populations.
“When I was Younger, My Story Belonged to Everyone Else”: Co-production of Resources for Adults Living with Craniosynostosis
Authors: Stock Nicola M. , Costa Bruna , Bannister William , Ashby Charlotte , Matthews Nammie , Hebden Louise , Melles Laura , Hilton-Webb Zoe , Smith Sally , Kane Kristian , Carter Lewis , Kearney Anna , Piggott Katie , Russell Charlotte , Wilkinson-Bell Karen
Published: March 2024

Objective

Despite growing recognition that congenital craniofacial conditions have lifelong implications, psychological support for adults is currently lacking. The aim of this project was to produce a series of short films about living with craniosynostosis in adulthood, alongside a psychoeducational booklet.

Design

The resources were developed using multiple focus groups and meetings attended by researchers, patient representatives, a leading charitable organisation, an award-winning film production company, clinicians, and other experts in the field.

Results

An online mixed-methods survey was developed based on prior work to request feedback on the acceptability and utility of the resources from the craniosynostosis community. While data collection to evaluate the resources is ongoing, preliminary results ( n = 36) highlight an acceptability rating of 100%.

Conclusions

The resources developed represent a step forward in addressing the unmet information and support needs of adults with craniosynostosis and highlight the benefits of co-production in research.
Outcomes of Tibiotalocalcaneal Arthrodesis vs Talar Body Prosthesis as Treatment of Collapsed Avascular Necrosis of the Talus: A 10- to 13-Year-Follow-up Retrospective Comparative Study
Authors: Harnroongroj Thos , Arunakul Marut , Reingrittha Pissanu , Chuckpaiwong Bavornrit , Angthong Chayanin , Tharmviboonsri Theerawoot , Lertwattanachai Penpun
Published: March 2024

Background:

Joint salvage surgeries such as tibiotalocalcaneal arthrodesis and talar prosthesis are commonly used in the surgical treatment of collapsed avascular necrosis of the talus (AVNT). However, differences in outcomes of these 2 surgical treatments are still inconclusive. This study compared the 10- to 13-year outcomes and 10-year survivorship rates of tibiotalocalcaneal arthrodesis and talar body prosthesis in the surgical treatment of collapsed AVNT.

Methods:

A retrospective comparative study was conducted of patients who underwent either tibiotalocalcaneal arthrodesis or talar body prosthesis implantation between 2005 and 2012. The demographic matching process resulted in 24 patients per treatment group. Clinical outcomes were evaluated using a numeric rating scale (NRS) of 2 hours of activities of daily living (ADL) and Foot and Ankle Ability Measure (FAAM) for ADL. Radiographic assessments included the incidence of nonunion, adjacent joint arthritis, and prosthesis loosening. The 10-year survivorship of both surgical treatments was calculated. A P value of less than .05 was considered statistically significant.

Results:

The median NRS of 2 hours of ADL and FAAM score for ADL were statistically significantly better in the talar body prosthesis group, with P values of .001 and <.001, respectively. The statistically significant differences in FAAM score for ADL exceeded the minimum clinically important difference. In the tibiotalocalcaneal arthrodesis group, nonunion was observed in 7 of 24 patients (29.2%). No prosthesis loosening was reported in the talar body prosthesis group. The 10-year survivorship was statistically significantly higher in talar body prosthesis than tibiotalocalcaneal arthrodesis (95.8% vs 70.8%), P = .023.

Conclusion:

Talar body prosthesis implantation in selected eligible patients demonstrated statistically significantly better 10- to 13-year clinical outcomes and higher 10-year survivorship compared with tibiotalocalcaneal arthrodesis in the surgical treatment of collapsed AVNT.

Level of Evidence:

Level III, retrospective cohort comparative study.
Polymethylmethacrylate (PMMA) Augmentation Enhances the Mechanical Characteristics of Midfoot Beam Constructs in Charcot Neuroarthropathy Cadaver Model
Authors: Pattisapu Naveen , Huang Dave T. , Porter Giselle , Owhonda Rebisi , Charlton Timothy , Gross Christopher , Thordarson David , Metzger Melodie F.
Published: March 2024

Background:

Even with the best conservative care, patients with Charcot neuroarthropathy (CN) of the foot and ankle often ulcerate, increasing their risk of infection, amputation, and death. Surgical fixation has been associated with risk of recurrent ulceration, potentially due to poor bone quality prone to recurrent deformity and ulceration. We propose midfoot beam reconstruction with PMMA augmentation as a novel means of improving fixation.

Methods:

A protocol was developed to create characteristic CN midfoot fragmentation both visually and fluoroscopically in each of 12 matched-pair cadaveric feet. Afterward, the pairs were divided into 2 groups: (1) midfoot beam fusion surgery alone, and (2) midfoot beam fusion surgery augmented with PMMA. A solid 7.0-mm beam was placed into the medial column and a solid 5.5-mm beam was placed across the lateral column. In the PMMA group, 8 to 10 mL of PMMA was inserted into the medial column. The hindfoot of each specimen was potted and the metatarsal heads were cyclically loaded for 1800 cycles, followed by load to failure while load and displacement were continually recorded.

Results:

One specimen in the beam alone group failed before reaching the 1800th cycle and was not included in the failure analysis. The midfoot beam only group demonstrated greater mean displacement during cycle testing compared with the PMMA group, P < .05. The maximum force (N), stiffness (N/mm), and toughness (Nmm) were all significantly greater in the group augmented with PMMA, P < .05.

Conclusion:

In a CN cadaveric model, PMMA augmentation significantly decreased gapping during cyclic loading and nearly doubled the load to failure compared with midfoot beams alone.

Clinical Relevance:

The results of this biomechanical study demonstrate that augmentation of midfoot beams with PMMA increases the strength and stiffness of the fusion construct. This increased mechanical toughness may help reduce the risk of nonunion and infection in patients with neuropathic midfoot collapse.
Inter-Establishment Complex Musculoskeletal Care Pathways in Montreal: Timeline of a Collaboration Involving a Research Team Within a Continuous Quality Improvement Initiative
Authors: Beauséjour Marie , Sasseville Martin , Vigné Aurélie , Riendeau Sophie , Gould Stephanie , Thorstad Kelly
Published: March 2024

Children and adolescents with complex musculoskeletal conditions may receive health care that requires at least 1 transfer between 4 specialized pediatric establishments in the Montreal region (Québec, Canada). This may result in challenges in navigating the system. A collaborative approach, aiming to make the inter-establishment care pathways seamless and to improve the integration of musculoskeletal health services, brought together key stakeholders including a research team. The aim of this paper is to describe the timeline of the collaborative approach’s key milestones and activities and, more specifically, to describe the context, process, and outputs of the involvement of researchers in support of a continuous quality improvement project based on an integrated approach. The descriptive timeline was constructed from a qualitative document analysis of the project-related gray literature (n = 80 documents) and was validated and interpreted with key stakeholders. The results showed how the collaborative project was set up and operated, as well as what solutions were developed and implemented. The strategies on how the research team was involved in the integrated approach in addition to its research activities were also described. Conclusions suggest practice recommendations for creating change processes by integrating research, service evaluation and clinical audit into quality improvement projects.
‘When Mom left for Mars’: Life narratives of first-generation Moroccan migrant mothers in Flanders
Authors: Miri Amal , Emmery Irma
Published: March 2024

Current discourses in Belgian politics about Moroccan Muslim women are deeply rooted in the first-generation family reunification policies of the 1960s. Today, (marriage) migrant women are still commonly described as victims of their ‘backward’ religious traditions and in need of protection for the sake of themselves, their children and society. Looking at the implications of these views for the women concerned, this article discusses the unique docufilm ‘When Mom Left for Mars’, which documents the life narrative of a first-generation Moroccan woman in The Netherlands. Based on this docufilm, we aim to (1) document how Belgian and Dutch first-generation migrant women can be compared with each other using Karl Mannheim’s ‘theory of generations’ and (2) engage in an intergenerational conversation with first-generation mothers and their daughters, as well as with mid-generation mothers, to gain more insight into their similarities, heritage and differences. More specifically, we explore the agency of these mothers using the analytical lens of ‘affective citizenship’, particularly attending to how they centralise mothering and care work to negotiate gender and belonging, and counter the challenges of marriage migration, motherhood and integration. The docufilm is, thus, used as a case study from which we consider the first-generation women as ‘cultural archives’, and as a methodological tool in facilitating in-depth interviews and group discussions.
With or without you: Career capital development as experienced by MBA alumni
Authors: Houldsworth Elizabeth , Tresidder Andrea , Rowson Tatiana
Published: March 2024

This article focuses on understanding the qualitatively different experiences of career development reported by the MBA alumni of a UK business school. Although the potential of the MBA to support career capital development has been previously identified, a thorough investigation into how this is experienced has been lacking. The study contributes to career capital theory in the context of post-experience management education in three ways. First, our findings report the development of career capitals, and we describe how these are manifested within the context of an MBA. Second, we identify five different experiences of career capital development, to which we ascribe the following labels: applying, achieving, collaborating, believing and transforming. These five different experiences contribute to theory by revealing the interrelationships and interdependencies between different forms of capital. Finally, we highlight that while it is possible to develop certain forms of career capital either with or without others, this is not the case for those involving personal transformation, which cannot be achieved alone. The article concludes with reflections on the implication of our findings for management educators, MBA teachers and researchers.
Against mastery: Epistemic decolonizing in the margins of the Business School
Authors: Abdallah Chahrazad
Published: March 2024

In this provocation, I argue that epistemic decolonizing is an opposition to the Master promulgator of knowledge, the Western/Eurocentric epistemic subject position. This epistemic refusal of mastery can only happen in the margins of the Business School, and as such, it is always an unfinished project whose incompleteness should be celebrated. To develop my argument, I proceed in three steps. First, I conceptualize the Business School as a postcolony, that is, a realm of extended epistemic domination rooted in the institution’s colonial historical role. Second, I suggest an alternative understanding of the margins not only rooted in spatiality, location, or identity but as a specific minoritarian epistemic position against mastery within the postcolony. These margins are not stable and immutable but relational, constantly being made, re-made, transformed, and negotiated. They are the location for an affirmative, generative and imaginative ongoing sabotage of epistemic domination. Finally, I offer that epistemic decolonizing as a minoritarian engagement, is unavoidably incomplete, unfinished, and unfinishable as knowledge always already exists and is always already weaved from a multiplicity of entangled historical, cultural, political, and disciplinary threads.
Rolling pairs with shifting contact geometry: Design, development, and validation
Authors: Amoroso Pedro , van Ostayen Ron AJ , de Rooij Matthijn B
Published: March 2024

This work introduces two innovative rolling pair concepts to minimize slippage and reduce mass in cam-roller systems of large-scale hydraulic drivetrains: The variable contact length and the Shifting Contact Geometry concepts. Both aim to improve traction in the low contact force phase in cyclically loaded rolling contacts. The shifting contact geometry concept was validated using three custom rolling contacts: a line contact, a double elliptical contact, and a combination of both (i.e., shifting contact geometry). The tests were conducted under synchronized cyclic loading to mimic the conditions in a hydraulic drivetrain. Furthermore, a model from previous work was implemented to make predictions and compare them against the experimental results. During preliminary tests, the double elliptical contact displayed superior tractive behavior than the line contact under the same load thanks to higher contact pressures. Under synchronized cyclic loading, the line contact displayed high sensitivity to applied resisting torques at low contact forces, leading to high slide-to-roll ratios and traction force peaks. In contrast, the rolling pair with shifting contact geometry exhibited minimum slippage even under high resisting torques, resulting in substantially lower (and in most cases negligible) slide-to-roll ratio and traction force peaks. The simulations also captured this behavior, proving the validity of the model for predicting and comparing the rolling-sliding dynamics of these two different rolling pairs. This study demonstrates that rolling pairs with shifting contact geometry can not only improve the tribological performance of cam-roller contacts in large-scale hydraulic drivetrains but also yield a more favorable dynamic behavior.
Responding to the danger of wrongful conviction for historical sexual abuse: A case for resurrecting abuse of process for delay?
Authors: Greenwood Holly
Published: March 2024

This article examines the potential risk of wrongful conviction for defendants facing historical sexual abuse charges where there is substantial delay. This risk arises from problems with truth-finding based on witness testimony, challenges posed by missing evidence and the increasing erosion of procedural safeguards. This article considers two recent proposals for reform, including first, whether the Court of Appeal should be more prepared to revisit the factual basis of decisions in historical sexual offence appeals; or second, whether there is a need to strengthen procedural safeguards at trial through the doctrine of abuse of process for delay. This article concludes that, whilst there would be advantages to broadening the grounds for appeal, the criminal courts should be more prepared to stay substantially delayed claims for abuse of process where there is missing evidence. The current approach has the potential to be unfair and fails to protect those defendants who are most disadvantaged by delayed claims.
Who relates to whom and according to which rationale? Visibility and advocacy in the Ugandan LGBT+ Twittersphere
Authors: Svensson Jakob , Larsson Anders Olof , Strand Cecilia
Published: March 2024

An increase in international funding for LGBT+ rights advocacy in Uganda has resulted in not only a mushrooming of organizations but also intra-community competition for visibility, attention, and limited resources. Against this backdrop, we set out to study how organizations relate to each other in the Ugandan LGBT+ Twittersphere. Following an analytical framework around rationalities of mediated participation, we study with whom Ugandan LGBT+ organizations relate through mapping retweets and @mentions emanating from selected Twitter accounts. The resulting network maps reveal a dividing line between more well-funded and internationally connected organizations and lesser established organizations. By supplementing the network analysis with qualitative readings of key accounts and semi-structured interviews, we conclude that access to international funds and negotiating visibility explains the network structures. The article thus reveals interesting Twitter practices, showing LGBT+ organizations use the platform as a means for negotiating and claiming space inside the Ugandan LGBT+ community.
Analysis of joint action between trainer and teachers in an in-service training system through the prism of a comparative approach in didactics
Authors: Brière Fabienne , Assude Teresa , Winder Claire Guille-Biel
Published: March 2024

Our study focuses on the effective implementation of constellations, an institutional scheme for the in-service training of primary school teachers of mathematics and French, established in France since 2020. Based on a bottom-up training model, this scheme aims to encourage reflexive analysis of practices among peers, based on professional needs. In this article, we adopt a comparative approach in didactics in the French tradition to studying the processes of co-development of the work object, entitled ‘problematic’, by trainer and teachers during training situations in two constellations in different disciplinary and geographical contexts. The methodology combines different levels of analysis in order to document the work of trainers in association with management by leaders, and to ascertain their practical epistemology.
Identify latent group structures in panel data: The classifylasso command
Authors: Huang Wenxin , Wang Yiru , Zhou Lingyun
Published: March 2024

In this article, we introduce a new command, classifylasso, that implements the classifier-lasso method (Su, Shi, and Phillips, 2016, Econometrica 84: 2215–2264) to simultaneously identify and estimate unobserved parameter heterogeneity in panel-data models using penalized techniques. We document the functionality of this command, including 1) penalized least-squares estimation of group-specific coefficients and classification of unknown group membership under a certain number of groups; 2) two lasso-type estimators with robust standard errors, namely, classifier-lasso and postlasso; and 3) determination of the number of groups based on an information criterion. We further develop some postestimation commands to display and visualize the estimation results.
Ordinary least squares and instrumental-variables estimators for any outcome and heterogeneity
Authors: Lee Myoung-jae , Han Chirok
Published: March 2024

Given an exogenous treatment d and covariates x, an ordinary least-squares (OLS) estimator is often applied with a noncontinuous outcome y to find the effect of d, despite the fact that the OLS linear model is invalid. Also, when d is endogenous with an instrument z, an instrumental-variables estimator (IVE) is often applied, again despite the invalid linear model. Furthermore, the treatment effect is likely to be heterogeneous, say, µ1(x), not a constant as assumed in most linear models. Given these problems, the question is then what kind of effect the OLS and IVE actually estimate. Under some restrictive conditions such as a “saturated model”, the estimated effect is known to be a weighted average, say, E{ ω(x) µ1(x)}, but in general, OLS and the IVE applied to linear models with a noncontinuous outcome or heterogeneous effect fail to yield a weighted average of heterogeneous treatment effects. Recently, however, it has been found that E{ ω(x) µ1(x)} can be estimated by OLS and the IVE without those restrictive conditions if the “propensity-score residual” d − E( d| x) or the “instrument-score residual” z−E( z| x) is used. In this article, we review this recent development and provide a command for OLS and the IVE with the propensity- and instrument-score residuals, which are applicable to any outcome and any heterogeneous effect.
“Little wars with the police”: Aesthetic arsenals and intellects of insult
Authors: Wall Tyler , McClanahan Bill
Published: March 2024

This paper describes the contemporary entanglement of “fuck the police” (FTP) and “all cops are bastards” (ACAB), locating each as examples of a growing rejection of an immiserating police power. We argue that these confrontational phrases emerge from the policed classes as relatively precise political diagnoses of a police power that is elementally concerned with the fabrication of capital’s social, racial, economic, and aesthetic order(s). In our view, the anti-police vitality communicated in these and other crude, combative, and dismissive symbolic confrontations with police is part of the necessary conditions for the revolutionary pursuit of a livable future.
Narrating Fabrics: Nostalgia in Animated Puppets’ Skin
Authors: Maselli Vincenzo
Published: March 2024

In recent years, many studies in the field of animation aesthetics have recognized that puppets’ materiality in stop-motion animation films is a powerful narrative tool. Starting from these premises, this article explores stop-motion films performed by fabric-skinned puppets and suggests that textile materials convey meta-narratives about loss and nostalgia. The analyses of the anthropological and expressive–sensorial dimensions of fabric indeed allow us to investigate the concepts of melancholy and nostalgia as intellectual and emotional experiences made possible thanks to the material characteristics of an artifact. To validate this hypothesis, three stop-motion short films are considered: the Japanese film Komaneko’s Christmas: The Lost Present (2009) by Tsuneo Goda and produced by the Dwarf studio; Christopher Kezelos’ film The Maker (2011); and Marionette (2012) by Thomas Tanner and Frayah Humphries. In these films, puppets’ materiality enhances either the melancholy aspects or the positive consequences of nostalgia and this interpretation can be formulated by looking at the ‘stories’ narrated by puppets’ fragile fabric skin as a manifestation of wistfulness. After providing an interdisciplinary overview of the main theoretical studies that explore concepts such as craftsmanship, puppets’ materiality and nostalgia from either animation, design or psychanalytical perspectives, the article defines three phenomenological dimensions of nostalgia suggested by fabric-skinned puppets’ material surface. Nostalgia is analysed as an emotion that proactively allows us to face the present by remembering the past, as an unconscious relational feeling that manifests human beings’ need to connect and as a pessimistic reaction to an inconsolable and irretrievable loss.
Disney’s Wagner Aesthetic: Music Drama in Pursuit of the Total Artwork
Authors: Barker Jason
Published: March 2024

Aside from Walt Disney’s reputation for renegade avant-gardism, ‘sentimental modernism’ and subliterary Americana, the German composer Richard Wagner’s pursuit of the Gesamtkunstwerk (total artwork) provides a coherent framework for interpreting the ‘music drama’ of the Disney studio’s Depression-era shorts of the 1930s and its feature films of the Golden Age (1937–1942). In citing Wagner and Adorno’s critique of him, the author argues that Disney follows Wagner in three key respects: (1) in his disavowal of the ‘work’ of art and corresponding objectification of Nature; (2) his espousal of technology and its ‘innovation’ as a means of attaining artistic perfection; and (3) his striving for a synaesthesia, or aesthetic unity of the senses, which would ultimately prove unsustainable given the commercial constraints of capitalist modernity.
Posthumous Portraits in Motion: Experimental Animation, Metamorphosis and Reflections on Mortality
Authors: Stewart Michelle
Published: March 2024

This article details an oil paint-on-glass animation depicting posthumous portraits of unclaimed deceased from a Johannesburg mortuary in South Africa. The creative project engages with Western traditions of posthumous, focusing on the iconography of the corpse. The author explores how these traditions are approached through the moving image, metamorphosis and experimental animation processes. The animation uses metamorphosis not just as a symbolic strategy to serve the idea of transformation – but also as a self-referential engagement with animation’s contradictory life-giving and destructive traits. The article and the creative project it illuminates present a critical awareness of the ethical concerns associated with representing the dead and the cultural and historical traditions from which this subject emerges.
Outcomes of percutaneous versus surgical tracheostomy in an Australian Quaternary Intensive Care Unit: An entropy-balanced retrospective study
Authors: Devanand Nilesh Anand , Thiruvenkatarajan Venkatesan , Liu Wai-Man , Sirisinghe Isuru , Court-Kowalski Stefan , Pryor Lee , Gatley Anne , Sethi Sandeep , Sundararajan Krishnaswamy
Published: March 2024

Background:

Studies comparing percutaneous tracheostomy (PT) and surgical tracheostomy (ST) complications in the critically ill patient population with high acuity, complexity, and severity of illness are sparse. This study evaluated the outcomes of elective PT versus ST in such patients managed at a quaternary referral center.

Aims:

The primary aim was to detect a difference in hospital mortality between the two techniques. The secondary aims were to compare Intensive Care Unit (ICU) mortality, complications (including stoma site, tracheostomy-related, and decannulation complications), ICU and hospital length of stay, and time to decannulation.

Methods:

This was a single-center retrospective observational study of ICU admission from August 2018 to August 2021. Patients were included if an elective tracheostomy was performed during their ICU admission. Patients with a pre-existing tracheostomy and those who underwent an obligatory tracheostomy requirement (e.g. total laryngectomy) were excluded. Cohorts were matched using Hainmueller’s entropy balancing. Binary data were evaluated using logistic regression and continuous data with ordinary least squares regression.

Results:

349 patients with a tracheostomy were managed in the ICU during the observation period. They were predominantly males (75% in PT; 67% in ST), with a mean age in the PT and ST group of (47; SD = 18) and (55; SD = 16), respectively. After exclusion, 135 patients remained, with 63 in the PT group and 72 in the ST group. Patients receiving ST were significantly older with a higher Body Mass Index (BMI) than the PT group. There were no significant differences in gender, Acute Physiological And Chronic Health Evaluation (APACHE) III, and the Australian and New Zealand Risk Of Death (ANZROD) between the two groups. There was no difference in hospital mortality between groups (OR 0.91, CI 0.26–3.18, p = 0.88). There were also no differences in ICU mortality, ICU and hospital length of stay, and time to decannulation. PT was associated with a greater likelihood of complications (OR 4.19; 95% CI 1.73–10.13; p < 0.01). PT was associated with a greater risk of complications in those who had this performed early (<10 days of intubation) as well as late (>10 days of intubation).

Conclusions:

Percutaneous tracheostomy was associated with higher complications compared to surgical tracheostomy. They were related to tracheostomy cuff deflation, stomal site bleeding and infection, sputum plugging, and accidental and failed decannulation. These findings have identified opportunities to improve patient outcomes.
Tendon ball arthroplasty and proximal carpal stabilization with tendon graft for advanced Kienböck’s disease
Authors: Zhang Wen , Hou Peng , Wu Tianyi , Ho Pak-Cheong , Sun Luyuan , Wang Chunyang
Published: March 2024

This study reports the surgical technique and outcomes of tendon ball arthroplasty combined with proximal carpal stabilization using the extensor carpi radialis longus tendon for treating advanced Kienböck’s disease. The collapsed lunate is excised and a tendon ball inserted as a spacer. A distally based extensor carpi radials longus graft is passed through the scaphoid, tendon ball and triquetrum, reconstructing the proximal carpal row. In total, 16 patients were included and the mean follow-up was 25 months. Pain improved from 5.6 preoperatively to 1.3 postoperatively on a 10-point visual analogue scale. Mean wrist motion improved by 17.8° and grip strength compared with the non-operative side increased by 22.1% on average. Radiographic outcomes demonstrated correction of scaphoid flexion and carpal height ratio. The modified tendon ball arthroplasty may be an alternative wrist salvage procedure for the treatment of advanced Kienböck’s disease.

Level of evidence: IV