bluuebunny/crossref_metadata_2025 huggingface dataset:
Stock market development and capital formation in selected African economies
Authors: Ayadi Olusegun Felix , Williams Johnnie
Published: August 2023

Purpose

This study aims to explore the possibility that securities markets in selected African countries of Egypt, Kenya, Nigeria and South Africa play a significant role in capital accumulation using panel data analysis. This is done by exploring the relationship between gross fixed capital formation on the one hand and financial market development indicators on the other hand. Thus, the study aims to examine if stock market size and liquidity are determinants of capital accumulation.

Design/methodology/approach

The analysis is based on annual times series from 1991 through 2017 spanning four African stock markets. The analysis utilizes the fixed-effect and random-effect econometric models. The Durbin–Wu–Hausman test is used to choose between the two models.

Findings

The key results indicate that stock market capitalization is a positive determinant of gross fixed capital formation. The market value traded and turnover have no relationship with capital formation. Therefore, the role of stock African stock markets in promoting capital accumulation and, subsequently, industrial growth in Africa is seriously questioned.

Originality/value

Only a handful of studies have examined the role of the African securities market in promoting capital accumulation. This study is unique in which it focuses on the leading stock markets in the four corners of Africa. The markets are from Egypt in the north, South Africa from the south, Nigeria from the west and Kenya from the east. These four markets account for a significant segment of all African markets.
Effects of product complexity on human learning in assembly and disassembly operations
Authors: Verna Elisa , Genta Gianfranco , Galetto Maurizio
Published: August 2023

Purpose

The purpose of this paper is to investigate and quantify the impact of product complexity, including architectural complexity, on operator learning, productivity and quality performance in both assembly and disassembly operations. This topic has not been extensively investigated in previous research.

Design/methodology/approach

An extensive experimental campaign involving 84 operators was conducted to repeatedly assemble and disassemble six different products of varying complexity to construct productivity and quality learning curves. Data from the experiment were analysed using statistical methods.

Findings

The human learning factor of productivity increases superlinearly with the increasing architectural complexity of products, i.e. from centralised to distributed architectures, both in assembly and disassembly, regardless of the level of overall product complexity. On the other hand, the human learning factor of quality performance decreases superlinearly as the architectural complexity of products increases. The intrinsic characteristics of product architecture are the reasons for this difference in learning factor.

Practical implications

The results of the study suggest that considering product complexity, particularly architectural complexity, in the design and planning of manufacturing processes can optimise operator learning, productivity and quality performance, and inform decisions about improving manufacturing operations.

Originality/value

While previous research has focussed on the effects of complexity on process time and defect generation, this study is amongst the first to investigate and quantify the effects of product complexity, including architectural complexity, on operator learning using an extensive experimental campaign.
The role of social media in building trust, self-perceived creativity and satisfaction for millennial entrepreneurs
Authors: Hamid Rahmad Solling , Ukkas Imran , Goso Goso , Abror Abror , Anwar Suhardi M. , Munir Abdul Razak
Published: August 2023

Purpose

This study aims to investigate the role of social media in increasing trust, self-perceived creativity and millennial entrepreneurial satisfaction.

Design/methodology/approach

The empirical analysis was conducted using a sample of 385 millennial entrepreneurs that were recruited for online survey. After conducting reliability and validity tests, the data were analyzed using partial least squares structural equation modeling.

Findings

The results showed that the quality of social media information had a direct and indirect positive and significant effect on trust and satisfaction. Social media marketing activities had a direct and indirect positive and significant effect on trust and self-perceived creativity. System Quality of social media also has a significant direct influence on trust. However, there is no direct relationship to satisfaction. Finally, social media marketing activities have a significant direct effect on trust and satisfaction.

Practical implications

This research can contribute to marketing experts and millennial entrepreneurs in improving the quality of advertising information and the credibility of social media used to support creativity, trust and satisfaction. In addition, marketing experts and millennial entrepreneurs with online-based communities should optimize their marketing activities on social media.

Originality/value

This study has shown a more comprehensive model of the relationship between information quality, system quality, social media marketing activities, self-perceived creativity, trust and satisfaction. This study also reveals a significant direct and indirect effect of social media marketing activities on satisfaction.
Hotel room access control: an NFC approach ecotourism framework
Authors: JosephNg P.S.
Published: August 2023

Purpose

This study aims to highlight that security and flexibilities remain the main points of contention in the cordiality business. This research points to planning a framework that empowers hotel users to get to the room using a mobile access key. Advancing secured facilities, mobile phone “Near Field Communication” (NFC) innovation as the entrance device by carrying out an application containing an imitated mobile key for explicit verification access is used.

Design/methodology/approach

The proposed system is evaluated by triangulation of experimental, numerical and rational evaluation using partial least square structural equation modeling (PLS-SEM) with Malaysian hotel guests and employees.

Findings

The discoveries with the hypothesis supported validated that the suggested solution can eliminate physical cards, boost protection and encourage a contactless ecosystem. Theoretical, management and societal contributions are discussed here.

Research limitations/implications

This experiment comes with the constraints that it was conducted in only two hotels and does not fully reflect the choices of a wider range of travellers. Secondly, the cost of existing NFC smart locks is still relatively high, and along with the development of technology, the price will decrease when supply exceeds demand.

Practical implications

To promote high-security attributes, NFC technology as the access system by implementing an application containing an emulated smart key for specific authentication access is used. The host-card emulation enables cost-effectiveness profit and initiating a defence system in the pandemic era.

Social implications

To promote high-security attributes, NFC technology is used as the access system by implementing an application containing an emulated smart key for specific authentication access. The host-card emulation enables cost-effectiveness profit and initiating a defence system in the pandemic era.

Originality/value

The novelty of this study comes from the use of commonly available smartphone NFC features that are yet to be applied in the tourism ecosystem. The research provokes the applied concept of mobile smartkeys.
Stairway to heaven or a placebo: the impact of lean leadership, through job demands, on hospital workers’ engagement and performance
Authors: van Kleeff Robert , van Harten Jasmijn , Knies Eva
Published: August 2023

Purpose

This study aims to examine to what extent the relationships between hospital workers’ perceptions of lean leadership behaviour, their engagement and the hospital unit’s perceived performance are mediated by job demands.

Design/methodology/approach

The data (n = 1,624) come from a lean implementation study in a Dutch hospital and are analysed using structural equation modelling in Mplus (v8.4).

Findings

The results confirm that lean leadership behaviour is related to employee engagement and hospital unit performance as perceived by employees, and these relationships are partially mediated through job demands. More specifically, the authors found that the type of job demand explains the direction of mediation effects. On the one hand, so-called challenging demands positively mediate the relationships between lean leadership behaviour and its outcomes. Conversely, hindering demands negatively mediates the relationship between lean leadership behaviour and perceived unit performance.

Practical implications

The authors recommend hospital organisations and human resources managers start by helping hospital leaders understand the underlying mechanisms that explain the effects of leadership on employees’ perceptions and, second, support their frontline leaders by providing training, coaching and feedback on how to influence job demands in a way that creates an optimal work environment for hospital employees.

Originality/value

The authors contribute to the literature by building upon insights from the job demands-resources model to explain the effects of lean leadership behaviour and by investigating the relevance of lean leadership in a hospital context, given the phenomenon’s strong roots in manufacturing.
Analyzing financial and economic development thresholds for carbon emission reduction: a dynamic panel regime-switching study across income levels
Authors: Yiadom Eric B. , Mensah Lord , Bokpin Godfred A. , Dziwornu Raymond K.
Published: August 2023

Purpose

This research investigates the threshold effects of the interplay between finance, development and carbon emissions across 97 countries, including 50 low-income and 47 high-income countries, during the period from 1991 to 2019.

Design/methodology/approach

Employing various econometric modeling techniques such as dynamic linear regression, dynamic panel threshold regression and in/out of sample splitting, this study analyzes the data obtained from the World Bank's world development indicators.

Findings

The results indicate that low-income countries require a minimum financial development threshold of 0.354 to effectively reduce carbon emissions. Conversely, high-income countries require a higher financial development threshold of 0.662 to mitigate finance-induced carbon emissions. These findings validate the presence of a finance-led Environmental Kuznet Curve (EKC). Furthermore, the study highlights those high-income countries exhibit greater environmental concern compared to their low-income counterparts. Additionally, a minimum GDP per capita of US$ 10,067 is necessary to facilitate economic development and subsequently reduce carbon emissions. Once GDP per capita surpasses this threshold, a rise in economic development by a certain percentage could lead to a 0.96% reduction in carbon emissions across all income levels.

Originality/value

This study provides a novel contribution by estimating practical financial and economic thresholds essential for reducing carbon emissions within countries at varying levels of development.
Factors affecting retailer social responsibility: a PLS-SEM approach in the context of Bangladesh
Authors: Islam Md. Farijul , Mofiz Uddin M.M. , Rahman Md. Mominur
Published: August 2023

Purpose

This study aims to examine the determinants of retailer social responsibility (RSR) in Old Dhaka City and their impact on RSR practices.

Design/methodology/approach

A cross-sectional design was used to collect primary data from 180 retailers through a questionnaire survey. The study used partial least squares structural equation modeling to analyze the data and examine the relationships among the determinants of RSR.

Findings

The study found that economic and ethical factors positively and significantly affect RSR practices, while social and environmental factors negatively but not significantly affect RSR practices. Cultural factors were also found to positively and significantly affect RSR practices.

Practical implications

This study provides insights for retailers and policymakers to enhance their RSR practices by considering economic, ethical and cultural factors. The findings also contribute to the existing literature on stakeholder theory by highlighting the importance of considering multiple stakeholders in RSR practices.

Originality/value

This study provides insights into the determinants of RSR in a unique setting in associating stakeholder theory and in Bangladesh, which has received limited attention in the literature on RSR.
Taking after a parent: Phenotypic resemblance and the professional familialisation of genomics
Authors: Hedgecoe Adam , Job Kathleen , Clarke Angus
Published: August 2023

This article draws on 2 years’ worth of ethnographic observation of team meetings to explore decision‐making in an NHS clinical genomics service. The focus of discussions was on ambiguous genomic results known as VUS or Variants of Uncertain Significance, which may be pathogenic but which also may turn out to be benign. In examining decision‐making around such results, we note how, in contrast to much policy and promotional material in this area, clinicians in these meetings (clinical geneticists and genetic counsellors) place great emphasis on parental phenotypes and whether the parents of a patient share the symptoms and signs of the suspected condition. This information is then combined with the result of genomic tests to decide whether the variant a patient has is responsible for their condition. This article explores the way in which clinicians attempt to flexibly enrol parents into genomic explanations through informal diagnosis of their possible phenotypes and the way in which actually meeting parents allows some clinicians to trump explanations based on documentary or photographic data. The paper sheds light on the way that earlier scholarly understandings of such decisions (around, say dysmorphology) remain relevant and explores claims that laboratory tests overrule clinical decision‐making.
Endoscopic resection of gastrointestinal stromal tumors
Authors: Cheng Bing Qian , Du Chen , Li Hui Kai , Chai Ning Li , Linghu En Qiang
Published: August 2023

Surgical resection is regarded as the main modality for the treatment of gastrointestinal stromal tumors (GISTs). With the advancement of endoscopic techniques and the introduction of super minimally invasive surgery (SMIS), endoscopic resection has been an alternative option to surgery. Recently, various endoscopic resection techniques have been used for the treatment of GISTs, including endoscopic submucosal dissection (ESD), endoscopic submucosal excavation (ESE), endoscopic full‐thickness resection (EFR), submucosal tunneling endoscopic resection (STER), and laparoscopic and endoscopic cooperative surgery (LECS). Studies on the safety and efficacy of the endoscopic treatment of GISTs have emerged in recent years. Endoscopic resection techniques have demonstrated to be effective and safe for the treatment of GISTs. However, there is currently no consensus on the optimal follow‐up strategy and the appropriate cut‐off value of tumor size for endoscopic resection. In this review we discussed the indications, preoperative preparation, procedures, efficacy, safety, postoperative evaluation, follow‐up, and perspectives of endoscopic resection modalities for GISTs.
Development Cooperation and Dependency: An Analysis of Brazilian‐Spanish Cooperation in Latin America Between 2010 and 2018
Authors: Palacios‐Cívico Juan Carlos , Maestro‐Yarza Irene , Martí‐González Xavier
Published: August 2023

Based on analysis of Brazilian‐Spanish cooperation in Latin America, this article aims to contribute to the discussion on whether South–South Cooperation (SSC) represents an alternative model with specific and differentiated objectives, or if it largely reproduces the constraints and interests traditionally associated with the North–South model, but with new institutions and actors. We start by analysing the main criticisms levelled at cooperation in the literature, emphasising the identification, review and comparison of the mechanisms of domination and dependency that derive from the bilateral and multilateral practices of traditional development cooperation. We then construct a synthetic dependency index to measure the ability of Spain and Brazil – as representative cases of North–South Cooperation (NSC) and SSC with Latin America – to influence the foreign trade, investment and foreign policy decisions of aid recipients, and to empirically contrast the lower level of verticality that much of the available literature assumes about SSC schemes. The empirical analysis suggests significant differences between NSC and SSC in terms of their ability to reproduce dependency patterns and validate the discourse that tends to identify the latter as an alternative cooperation model.
Full block or split block?—Comparison of two different autogenous block grafting techniques for alveolar ridge reconstruction
Authors: Mertens Christian , Büsch Christopher , Goldenbaum Konrad , Ristow Oliver , Hoffmann Jürgen , Wang Hom‐Lay , Hoffmann Korbinian Jochen
Published: August 2023

Objective

To evaluate radiographic bone gain after alveolar ridge augmentation with two different designs of autogenous block graft harvested from the mandible.

Materials and Methods

Alveolar ridge defects were evaluated by preoperative cone beam computed tomography (CBCT) and grafted in a staged approach using intraoral block grafts. The ridge augmentation was either performed using the full‐block technique (group 1) or the split‐block technique (cortical plate with autogenous bone chips) (group 2). After 4 months of bone healing, a further CBCT scan was performed before implant placement. Horizontal and vertical bone gain were measured.

Results

In this retrospective study, 91 patients were grafted with block grafts (36 patients with full‐block grafts; 55 patients with split‐block grafts) resulting in 171 block grafts in total. The mean horizontal bone gain was 3.37 ± 0.71 mm in group 1 and 5.79 ± 2.20 mm in group 2. A linear mixed‐effect model also showed a statistically significant group difference (p < 0.001, estimate: 3.455, 95% CI: [2.082–4.829]). The mean vertical bone gain was 2.85 ± 0.73 mm in group 1 and 7.60 ± 1.87 mm in group 2. A linear mixed‐effect model also showed a statistically significant group difference (p: 0.029, estimate: 3.126, 95% CI: [0.718–5.557]). Mean marginal bone level was 0.33 ± 0.37 mm (group 1) and 0.17 ± 0.29 mm (group 2).

Conclusion

The split‐block technique resulted in a greater bone gain than the full‐block technique. This effect was observed in both the vertical and the horizontal dimensions.
A survey of treatment preferences of UK surgeons in the treatment of pilonidal sinus disease
Authors: Lee Matthew J. , Strong Emily B. , Lund Jon , Hind Dan , Brown Steven R. ,   the PITSTOP Management Group
Published: August 2023

Aim

Pilonidal sinus is a common surgical condition which impacts a young and economically active population. There are limited data to guide treatment in this condition. The aim of this work was to assess current practice.

Method

A survey was developed as part of the PITSTOP study. It included questions on volume of practice, treatment preferences and training. The survey was delivered to consultant surgeons with a UK practice through social media, specialty surgical societies and through PITSTOP sites. Descriptive statistics were reported.

Results

Of the 200 people who received a link to the questionnaire, 109 completed it (response rate 54.5%). Respondents treated a median of 15 patients per year, with 20% of these having recurrent disease. Estimates of recurrence were higher than reported in the literature and higher than in a survey 10 years ago. Nearly 50% of surgeons advocate nonsurgical treatment in some patients despite limited evidence. Two thirds practised interventions not favoured by guidelines, including excision and leave open and midline closure techniques. Invasive procedures tended to be favoured when minimally invasive procedures may be appropriate. Surgical training programmes were the key training setting for commonly offered procedures, with few other training opportunities reported. For some procedures, no formal training had been given.

Conclusion

This survey highlights issues with quality in pilonidal surgery in the UK, with persistence of potentially outdated techniques, no consistent treatment escalation plan, a suggestion of under‐ or overtreatment of disease and a high perception of failure. This may relate to the current system of training and lack of evidence‐based guidance.
The influence of defaecating proctograms on clinical decision‐making in pelvic floor disorders
Authors: Gomes Leanora , Varghese Chris , Collinson Rowan J. , Hayes Julian L. , Parry Bryan R. , Milne David , Bissett Ian P.
Published: August 2023

Aim

Defaecating proctogram (DP) studies have become an integral part of the evaluation of patients with pelvic floor disorders. However, their impact on treatment decision‐making remains unclear. The aim of this study was to assess the concordance of decision‐making by colorectal surgeons and the role of the DP in this process.

Method

Four colorectal surgeons were presented with online surveys containing the complete history, examination and investigations of 106 de‐identified pelvic floor patients who had received one of three treatment options: physiotherapy only, anterior Delorme's procedure or anterior mesh rectopexy. The survey assessed the management decisions made by each of the surgeons for the three treatments both before and after the addition of the DP to the diagnostic work‐up.

Results

After the addition of the DP results; treatment choice changed in 219 (52%) of 424 surgical decisions and interrater agreement improved significantly from κ = 0.26 to κ = 0.39. Three of the four surgeons reported a significant increase in confidence. Agreement with the actual treatments patients received increased from κ = 0.21 to κ = 0.28. Intra‐anal rectal prolapse on DP was a significant predictor of a decision to perform anterior mesh rectopexy.

Conclusion

The DP improves interclinician agreement in the management of pelvic floor disorders and enhances the confidence in treatment decisions. Intra‐anal rectal prolapse was the most influential DP parameter in treatment decision‐making.
Comparative functional and structural analysis of Pseudomonas aeruginosad‐alanine–d‐alanine ligase isoforms as prospective antibiotic targets
Authors: Pederick Jordan L. , Woolman Jessica C. , Bruning John B.
Published: August 2023

Pseudomonas aeruginosa is a major human pathogen in the healthcare setting. The emergence of multi‐drug‐resistant and extensive drug‐resistant P. aeruginosa is of great concern, and clearly indicates that new alternatives to current first‐line antibiotics are required in the future. Inhibition of d‐alanine–d‐alanine production presents as a promising avenue as it is a key component in the essential process of cell wall biosynthesis. In P. aeruginosa, d‐alanine–d‐alanine production is facilitated by two isoforms, d‐alanine–d‐alanine ligase A (PaDdlA) and d‐alanine–d‐alanine ligase B (PaDdlA), but neither enzyme has been individually characterised to date. Here, we present the functional and structural characterisation of PaDdlA and PaDdlB, and assess their potential as antibiotic targets. This was achieved using a combination of in vitro enzyme‐activity assays and X‐ray crystallography. The former revealed that both isoforms effectively catalyse d‐alanine–d‐alanine production with near identical efficiency, and that this is effectively disrupted by the model d‐alanine–d‐alanine ligase inhibitor, d‐cycloserine. Next, each isoform was co‐crystallised with ATP and either d‐alanine–d‐alanine or d‐cycloserine, allowing direct comparison of the key structural features. Both isoforms possess the same structural architecture and share a high level of conservation within the active site. Although residues forming the d‐alanine pocket are completely conserved, the ATP‐binding pocket possesses several amino acid substitutions resulting in a differing chemical environment around the ATP adenine base. Together, these findings support that the discovery of dual PaDdlA/PaDdlB competitive inhibitors is a viable approach for developing new antibiotics against P. aeruginosa.
Rucaparib inhibits lung adenocarcinoma cell proliferation and migration via the SHCBP1/CDK1 pathway
Authors: Dai Yue , Hu Changpeng , Zhou Huyue , Liu Wuyi , Lai Wenjing , Xu Rufu , Liao Jiaxing , Wang Jie , Li Guobing , Zhang Rong
Published: August 2023

Src homolog and collagen homolog binding protein 1 (SHCBP1) binds to the SH2 domain of SHC‐transforming protein 1 (SHC1) and is involved in midbody organization and cytokinesis completion. SHCBP1 has been reported to be a cancer driver gene, promoting cancer progression. However, the functional role and underlying mechanism of SHCBP1 in regulating lung adenocarcinoma (LUAD) cell proliferation and migration are incompletely understood. Here, we discovered that SHCBP1 is overexpressed in LUAD tissues and is associated with a poor prognosis. SHCBP1 knockdown inhibited LUAD cell proliferation and migration by arresting the cell cycle and preventing epithelial–mesenchymal transition (EMT) via decreasing cyclin‐dependent kinase 1 (CDK1) expression. Mechanistically, CDK1 overexpression reversed SHCBP1 knockdown‐induced inhibition of proliferation and migration, confirming CDK1 as a key downstream target of SHCBP1. In addition, we proposed that rucaparib may be a small‐molecule inhibitor of SHCBP1 and validated both in vitro and in vivo that rucaparib inhibits cell proliferation and migration via suppression of the SHCBP1/CDK1 pathway in LUAD. Our study elucidates a newly identified role of SHCBP1 in promoting cell proliferation and migration in LUAD, and suggests rucaparib as a potential inhibitor for LUAD treatment.
Arabidopsis T‐DNA mutants affected in TRDMT1/DNMT2 show differential protein synthesis and compromised stress tolerance
Authors: Wadhwa Nikita , Kapoor Sanjay , Kapoor Meenu
Published: August 2023

TRDMT1/DNMT2 belongs to the conserved family of nucleic acid methyltransferases. Unlike the animal systems, studies on TRDMT1/DNMT2 in land plants have been limited. We show that TRDMT1/DNMT2 is strongly conserved in the green lineage. Studies in mosses have previously shown that TRDMT1/DNMT2 plays a crucial role in modulating molecular networks involved in stress perception and signalling and in transcription/stability of specific tRNAs under stress. To gain deeper insight into its biological roles in a flowering plant, we examined more closely the previously reported Arabidopsis SALK_136635C line deficient in TRDMT1/DNMT2 function [Goll MG et al. (2006) Science 311, 395–398]. RNAs derived from Arabidopsis Dnmt2‐deficient plants lacked m5C38 in tRNAAsp. In this study, by transient expression assays we show that Arabidopsis TRDMT1/DNMT2 is distributed in the nucleus, cytoplasm and RNA‐processing bodies, suggesting a role for TRDMT1/DNMT2 in RNA metabolic processes possibly by shuttling between cellular compartments. Bright‐field and high‐resolution SEM and qPCR analysis reveal roles of TRDMT1/DNMT2 in proper growth and developmental progression. Quantitative proteome analysis by LC–MS/MS coupled with qPCR shows AtTRDMT1/AtDNMT2 function to be crucial for protein synthesis and cellular homeostasis via housekeeping roles and proteins with poly‐Asp stretches and RNA pol II activity on selected genes are affected in attrdmt1/atdnmt2. This shift in metabolic pathways primes the mutant plants to become increasingly sensitive to oxidative and osmotic stress. Taken together, our study sheds light on the mechanistic role of TRDMT1/DNMT2 in a flowering plant.
The collaborative study on the genetics of alcoholism: Sample and clinical data
Authors: Dick Danielle M. , Balcke Emily , McCutcheon Vivia , Francis Meredith , Kuo Sally , Salvatore Jessica , Meyers Jacquelyn , Bierut Laura J. , Schuckit Marc , Hesselbrock Victor , Edenberg Howard J. , Porjesz Bernice ,   COGA Collaborators, Kuperman Samuel , Kramer John , Bucholz Kathleen
Published: August 2023

The collaborative study on the genetics of alcoholism (COGA) is a multi‐site, multidisciplinary project with the goal of identifying how genes are involved in alcohol use disorder and related outcomes, and characterizing how genetic risk unfolds across development and in conjunction with the environment and brain function. COGA is a multi‐generational family‐based study in which probands were recruited through alcohol treatment centers, along with a set of community comparison families. Nearly 18,000 individuals from >2200 families have been assessed over a period of over 30 years with a rich phenotypic battery that includes semi‐structured psychiatric interviews and questionnaire measures, along with DNA collection and electrophysiological data on a large subset. Participants range in age from 7 to 97, with many having longitudinal assessments, providing a valuable opportunity to study alcohol use and problems across the lifespan. Here we provide an overview of data collection methods for the COGA sample, and details about sample characteristics and comorbidity. We also review key research findings that have emerged from analyses of the COGA data. COGA data are available broadly to researchers, and we hope this overview will encourage further collaboration and use of these data to advance the field.
A novel prosthesis presentation test to screen for cognitive and functional decline
Authors: Srinivasan Murali , Duong Stephan , Trombert Veronique , Kalberer Nicole , Zekry Dina , Herrmann François R. , Delavy Joris , Gold Gabriel , Müller Frauke
Published: August 2023

Objectives and background

To validate a novel screening test for cognitive and functional decline in older patients rehabilitated with complete removable dental prostheses (CRDPs).

Materials and methods

Edentate old in‐patients rehabilitated with CRDPs were included in this study. Participants were requested to remove their prostheses before their intraoral examinations. The prostheses were then presented in an inverted orientation. Participants had to correct the orientation of the prostheses and insert them in the appropriate jaws. The test was repeated after the intraoral exam. Appropriate statistical models were used (⍺ = .05) to associate the test results with the participants' mini‐mental state examination (MMSE) score, functional independence measure (FIM), age and sex.

Results

Among the 86 participants (mean‐age: 85.4 ± 6.4 years; mean MMSE: 19.8 ± 5.5; mean FIM: 77.9 ± 20.8), 21 (24.4%) failed to correctly insert the prosthesis. The prosthesis presentation test (PPT) was associated with the FIM but not the MMSE. Regression models further confirmed an association with age (P = .043), but not sex. Additional analyses revealed the PPT test is associated with the FIM's cognitive sub‐sets of memory, problem solving and social interaction.

Conclusion

The PPT is a novel, simple and quick screening tool that can help detect functional difficulties in older people. It can easily be performed during an oral examination. Future studies are needed to determine whether the PPT can be used to detect deficits in executive function, as a complement to the MMSE and also as a first assessment of a patient's ability to manage dentures independently.
In family we trust—In good and bad times
Authors: Masset Philippe , Poretti Cédric , Weisskopf Jean‐Philippe
Published: August 2023

This short report investigates the stock market behavior of Swiss companies during the COVID‐19 pandemic. Results suggest that family firms performed better during the outbreak and post‐lockdown periods than widely‐held firms. Family firms also displayed a larger abnormal trading volume drop than widely‐held companies. In size‐sorted subsamples, the volume difference appears more pronounced for smaller firms. We explain these findings by family firms, especially smaller ones, predominantly attracting investors with a long‐term horizon. Such investors are less likely to sell during market turmoil, making family firms not only less liquid but also less sensitive to market fluctuations.
Ultrafast crystallization and sintering of Li1.3Al0.3Ti1.7(PO4)3 glass through flash sinter‐crystallization
Authors: Campos João V. , Lavagnini Isabela R. , Zallocco Vinicius M. , Jesus Lilian M. , Rodrigues Ana C. M.
Published: August 2023

Flash sinter‐crystallization (FSC) is a new technique for concurrently crystallizing and sintering glasses, derived from flash sintering. In this study, we explore, for the first time, the use of FSC as a processing method for producing Li1.3Al0.3Ti1.7(PO4)3 (LATP) glass ceramics. Using FSC, LATP with NaSICON structure is produced at a furnace temperature as low as 460°C and a processing time of 5 min. The FSC‐processed samples with different current density limits were compared with those conventionally sinter‐crystallized (CSC) at 950°C for 1 h. We show that FSC can significantly improve the densification of LATP glass ceramics due to the volumetric high heating rate. Furthermore, the LATP samples processed by FSC exhibit superior total ionic conductivity than those processed by CSC, also surpassing the reported results for LATP with similar levels of densification. Therefore, our results suggest that FSC is a promising method for processing glass ceramics, particularly for materials with high crystallization kinetics like LATP, opening up new possibilities for the production of solid electrolytes.
The perception of patients, mothers and healthcare professionals regarding introduction of home visits for adolescents with type 1 diabetes
Authors: Kofoed Poul‐Erik , Lisbjerg Susanne , Thomsen Jane
Published: August 2023

Background and Objectives

Despite advancements in diabetes management, a subgroup of patients does not achieve an acceptable level of metabolic control. To achieve treatment goals for high‐risk patients, a higher frequency of contact with healthcare professionals is essential. However, socioeconomic challenges often lead to nonattendance at the outpatient clinic. Therefore, home visits were introduced as a supplement/an alternative to consultations at the paediatric diabetes clinic. The aim of this study was to uncover the perception of patients, mothers and healthcare professionals regarding home visits versus consultations at the outpatient clinic in order to being able to improve the services offered.

Methods

Semistructured interviews with patients, mothers and healthcare professionals were conducted to explore the experiences and perspectives of the concept at two paediatric diabetes clinics in Denmark. Paired t tests were used to compare the glycated hemoglobin A1c (HbA1c) levels at the start of the intervention with HbA1c 1 year before and HbA1c at the end of the intervention.

Results

Both patients, mothers and healthcare professionals found consultations in familiar surroundings to result in stronger relationships between healthcare professionals and families, creating greater opportunities to discuss personal issues aimed at improving the outcome of diabetes. Furthermore, home visits facilitated finding alternative methods of helping patients and the families integrating diabetes into everyday life.

Conclusion

Overall, home visits were found to contribute toward creating a more constructive relationship. However, it was still a challenge to keep the scheduled appointments, and during this short study, no improvement in metabolic control could be observed.
Additively manufactured devices with varying designs and sizes for acquiring initial intraoral implant scans
Authors: Guirao Sergi , Llansana Ferran , Button Heather , Yilmaz Burak , Kois John C. , Revilla‐León Marta
Published: August 2023

Dental literature has reported greater intraoral scanning accuracy when implant scan bodies (ISBs) are connected compared with non‐connected methods. Initial intraoral digital implant scans are required for the fabrication of a custom framework to connect implant scan bodies (IOSFix; IOSFix Dental). This calibrated metal framework is used to acquire definitive intraoral implant scans. However, the acquisition of initial intraoral implant scans can be challenging when ISBs are not connected. This article describes a step‐by‐step technique for connecting ISBs by using additively manufactured devices to acquire initial intraoral implant scans. This technique aims to facilitate the recording of initial intraoral implant scans, provide different device designs and sizes to connect ISBs, and reduce chairside time.
Comparison of electronic versus mechanical torque‐limiting devices for dental implants: An in vitro study
Authors: Faraj Mohaad A. , Bidra Avinash S. , Taylor Thomas D. , Kuo Chia‐Ling
Published: August 2023

Purpose

To determine the accuracy of new electronic torque‐limiting devices (ET) when compared to new and used conventional‐style beam‐type (BT) mechanical torque‐limiting devices and hand‐piece style (HS) mechanical torque‐limiting devices. The secondary purpose was to compare any difference in accuracy between new and used mechanical torque‐limiting devices, and any difference in accuracy when used on a straight versus an angled screw channel abutment.

Materials And Methods

A total of five torque‐limiting devices were used to obtain 2000 readings under standardized conditions. An implant analog was fastened into a digital torque meter, to which an abutment was connected. Pre‐determined torque values of 15 Ncm and 35 Ncm were applied, and actual torque values were recorded. A straight and an angled abutment were used to record 1000 readings each using the five torque‐limiting devices. An overall Kruskal‐Wallis test was applied to compare the median deviation among devices followed by a pairwise comparison ( = 0.05).

Results

For a target torque value of 15 Ncm on a straight abutment, the electronic device (ET) was statistically more accurate than the beam type (BT) new (p < 0.001) and used (p < 0.048) devices but less accurate than the hand‐piece style (HS) used device (p < 0.001). On an angled abutment for a target value of 15 Ncm, the electronic device (ET) was statistically more accurate than hand‐piece style (HS) new and used devices (p < 0.001). For a target torque value of 35 Ncm on a straight abutment, the ET was statistically more accurate than the HS new device (p < 0.001) but less accurate than the BT new device (p < 0.001). On an angled abutment for a target value of 35 Ncm, the electronic device (ET) was statistically less accurate than the beam‐type (BT) new device (p < 0.001), the beam‐type (BT) used device (p = 0.001), and the hand‐piece style (HS) used device (p < 0.001). The electronic device (ET) was the only device accurate within the ISO standard of accuracy of 6% for each of the target torque value/abutment design combinations. There was no statistically significant difference related to the type of abutment used (angled vs. straight).

Conclusions

Electronic torque limiting devices (ET) are an acceptable method for delivering torque for implant restorations for straight and angled abutments at 15 Ncm and 35 Ncm torque values. Conventional style beam‐type (BT) mechanical torque‐limiting devices are a simple, predictable, validated, and inexpensive tool for delivering accurate torque at 15 Ncm and 35 Ncm torque values. The hand‐piece style (HS) mechanical torque‐limiting devices are predictable to deliver 15 Ncm torque values.
Optimal insurance contract design with government disaster relief
Authors: Hinck Sebastian
Published: August 2023

I examine the design of optimal insurance contracts considering the possibility of government disaster relief payments. This work focuses on the impact of (risky and ambiguous) government disaster relief on the shape of optimal private insurance contracts. I demonstrate that the optimal insurance contract is a straight deductible contract in the case of a fixed probability of government relief. This result is robust to ambiguity in the probability of relief payments, even for ambiguity‐averse decision makers. If government disaster relief becomes more likely for larger losses, then the optimal insurance contract features coinsurance above a deductible. I also extend this analysis to more general stochastic dominance relationships between disaster relief and loss magnitude.
Form Shear Stress Correction in Bulk Flow Analysis of Grooved Seals Based on Effective Film Thickness
Authors: Gibbons Nathaniel , Goyne Christopher
Published: August 2023

Bulk flow models for grooved annular seals provide computationally efficient static and dynamic response predictions, though heavy reliance on empirical relationships often leads to undesirable levels of uncertainty. The flow complexity caused by the grooves adds difficulty to shear stress modeling for these seals. This study seeks to improve shear stress modeling for grooved seals through the identification and quantification of the additional bulk flow shear stress contributions within the groove region. Through single groove computational fluid dynamics (CFD) simulations and an effective film thickness analysis framework, the additional groove shear stress component is identified as a form shear stress (FSS) due to its clear relationship to the effective film thickness behavior. The FSS is quantified as a correction to traditional shear stress definitions. Predictive models for the FSS are developed as functions of the ratio of circumferential to axial Reynolds number and the total resultant Reynolds number. Implementation of the FSS models into a simplified bulk flow method delivers leakage predictions for three seal cases within 10% of the experimental results and qualitative agreement in predicted circumferential velocity profiles while eliminating the need for an assumed groove loss coefficient. This is the first paper to utilize an effective film thickness-based procedure to quantify and model the FSS component in grooved seal bulk flow analysis. The demonstrated predictive capability and widespread applicability of the models and approach presented in this paper provide an avenue for significant improvements in grooved seal bulk flow prediction accuracy through improved shear stress modeling.
Experimental Tribological Study on Additive Manufactured Inconel 718 Features Against the Hard Carbide Counter Bodies
Authors: Basha M. M. , Sankar M. R.
Published: August 2023

In past years, machining processes have been required when fabricating the complex Inconel 718 parts, and these processes cause undesired tensile residual stresses. Inconel 718 also exhibits extreme work hardening throughout the machining process. To avoid these issues, recently, Inconel 718 parts with high geometric complexity and dimensional accuracy, the laser powder bed fusion (LPBF) process, which belongs to additive manufacturing, has been extensively used. These Inconel 718 parts with LPBF processing are frequently utilized in various industries, including aerospace, automotive, pharmaceutical, and food processing, because of their high strength, biocompatibility, and corrosion resistance. Wear resistance is essential in addition to these properties for designing and crushing applications. In this paper, tribological tests were conducted on the LPBF-processed Inconel 718 parts and compared to casted Inconel 718 parts against the four types of counter bodies, namely boron carbide, silicon carbide, tungsten carbide, and titanium carbide. The studies were carried out for 30 min with a constant load of 5 N, frequency of 10 Hz, and stroke length of 1 mm. In comparison to casted samples, LPBF-processed samples showed low coefficient of friction (COF) values. The highest COF was observed on the cast Inconel 718 against the tungsten carbide counter body. The wear mechanisms were studied using scanning electron microscopy.
Reinforcing Cold-Sprayed Al Coatings With Boron Nitride Nanotubes and Micro-Boron Carbide and Their Effect on Surface Mechanical and Dry Sliding Behavior
Authors: Kulkarni Achyuth , Tauber David , Ansell Troy Y.
Published: August 2023

This investigation explores the reinforcement effects of both boron nitride nanotubes (BNNTs) and micro-boron carbide (μB4C) on the tribological and mechanical properties of aluminum matrix composite (MMC) cold-sprayed coatings. The synthesis process involved high-energy ball milling (HEBM) and cold spraying with helium to create four distinct Al-MMC coatings on a magnesium (AZ31) substrate. These coatings consisted of pure aluminum, a composition containing 4 vol% B4C, a composition with 4 vol% BNNTs, and a composition with 2 vol% B4C and 2 vol% BNNTs. Successful dispersion of nanoparticles within the aluminum matrix was achieved. The hardness of the coatings exhibited significant improvements compared to the pure aluminum coating. Specifically, the Al-BNNT coating showed a hardness increase of 14.1%, the Al-B4C-BNNT coating displayed a hardness increase of 20.8%, and the Al-B4C coating demonstrated the highest increase of 33.3% over the pure aluminum coating. Furthermore, the Al-B4C coating exhibited remarkable reductions in wear volume loss and wear track depth, amounting to eight and two orders of magnitude, respectively. Adhesion testing revealed that the Al-B4C-BNNT coating failed cohesively, while the pure aluminum coating failed adhesively at approximately the same force. The Al-B4C coating experienced a combination of the two failure modes at a 31.2% increase in force compared to the pure aluminum coating. Tensile testing stress versus strain curves indicated that the load was partially supported by the cold spray coating until the coating ruptured.
Analysis of Displacement-Controlled Fretting Between Crossed Parabolic Cylinders in Elasto-Plastic Contacts
Authors: Guo Tieneng , Shi Hao , Ji Ruguo , Li Bo , Wang Chenhang
Published: August 2023

In practice, it is difficult to avoid the axis angle deviation when some regular surfaces are in micro-sliding, such as gears and machined surfaces. In order to better investigate the micro-motion contact characteristics, a crossed paraboloidal contact model under frictional condition is proposed to simulate both tangential displacement-controlled fretting and the evolution of the energy dissipation in a load cycle. By deriving the theoretical of the normal and tangential contact course of the model, the load–displacement curves during initial loading, unloading, and reloading stage are presented. On this basis, the hysteresis curve is then obtained by integrating the closed area surrounded by load–displacement during unloading and reloading, which also means that the empirical formulation for microslip in a load cycle is constructed. This study also reveals the plastic yield phenomenon under pure normal loading and plastic shakedown behavior caused by cyclic reciprocating displacement loads. In addition, the research on the junction growth, the evolution of tangential load, and hysteresis curve with different COFs under multiple-cycle load is also carried out. The implications of involved parameters, such as friction coefficient, axis intersection angle, normal load, and so on, are discussed with respect to hysteresis curve shape and energy dissipation. The difference in hysteresis and energy dissipation curves between the paraboloidal contact model and other classic contact models is then presented. It is discovered by comparison with other models that the paraboloidal contact model presents a relatively high energy dissipation in a load cycle.