1
|
Lee KT, Bulls HW, Hoogland AI, James BW, Colon-Echevarria CB, Jim HSL. Chemotherapy-Induced Peripheral Neuropathy (CIPN): A Narrative Review and Proposed Theoretical Model. Cancers (Basel) 2024; 16:2571. [PMID: 39061210 PMCID: PMC11274737 DOI: 10.3390/cancers16142571] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2024] [Revised: 07/03/2024] [Accepted: 07/11/2024] [Indexed: 07/28/2024] Open
Abstract
BACKGROUND Chemotherapy-induced peripheral neuropathy (CIPN) is a common and debilitating symptom experienced by cancer survivors. Despite the burden of CIPN-related symptoms, interventions remain limited. OBJECTIVES This narrative review seeks to propose a framework for CIPN predisposing, precipitating, and perpetuating factors (3Ps), which will provide a foundation for future research and clinical interventions aimed at mitigating CIPN-related symptoms and morbidity. METHODS A comprehensive literature search was performed using PubMed, guided by keywords related to "chemotherapy-induced peripheral neuropathy." Studies were limited to those with full text available in English. RESULTS Predisposing factors outlined in this framework, such as older age and comorbid conditions, can be used to identify patients who have a higher risk of developing CIPN. The major precipitating factor of CIPN is the delivery of chemotherapy to peripheral nerves, which may be mitigated via cryotherapy or compression therapy during chemotherapy. Perpetuating factors can offer insight into psychological, cognitive, and behavioral modifications that could be treatment targets for CIPN management. CONCLUSION The proposed 3P model can guide the development of effective interventions for CIPN by suggesting modifiable psychological and behavioral treatment targets that may mitigate the impact of CIPN for cancer patients.
Collapse
|
2
|
Elst S. [The cultural intermediary model, a source of alternative views on nursing activity in palliative care]. SOINS; LA REVUE DE REFERENCE INFIRMIERE 2024; 69:31-36. [PMID: 38880590 DOI: 10.1016/j.soin.2024.04.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2024]
Abstract
With the aim of describing the activities of nurses in mobile home palliative care teams in the Brussels Region, the study Nursing practices in palliative care in Brussels outpatient mobile teams took the cultural intermediary model as its theoretical framework. This model is based on in-depth research into the history of the nursing discipline. This article provides an overview of this European conceptual model, its integration into a descriptive study, and highlights some of its contributions.
Collapse
|
3
|
Mei Z, Zhang Y, Fan Q, Luo S, Luo S. The effects of mobile phone dependence on athletic performance and its mechanisms. Front Psychol 2024; 15:1391258. [PMID: 38817835 PMCID: PMC11138105 DOI: 10.3389/fpsyg.2024.1391258] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2024] [Accepted: 05/02/2024] [Indexed: 06/01/2024] Open
Abstract
Mobile phone dependence (also known as internet dependence, MPD), defined as a problematic behavior characterized by excessive use or intermittent craving to use a mobile phone, results in various social, behavioral, and affective problems in daily life. In sports, MPD is directly related to the physical and mental health and sports performance of athletes. The individual and environmental factors, neurobiological mechanisms and theoretical models of MPD affecting athletic performance were analyzed by reviewing previous studies, aiming to construct effective training and development protocols to prevent and control the occurrence of MPD in athletes. At present, athletic performance can be affected by MPD through individual factors and environmental factors. The neurobiological mechanisms between the two are based on the brain reward system and microwave radiation from mobile phones, with athletic performance being restricted by alterations in the corresponding brain regions. Relevant theoretical models mainly include the social cognitive model of self-regulation and the integrative model of self-control, which explain the interrelationship between MPD and athletic performance from the perspectives of athletes' self-regulation and self-control, respectively. As an emerging phenomenon, the influence pathways and mechanisms by which MPD affects athletic performance need to be further investigated. A longitudinal perspective should be adopted to trace the dynamic impact relationship between the two, and developing relevant theoretical frameworks from an interdisciplinary research perspective should be valuable for providing theoretical support for coaches and sports administrators to formulate scientific training protocols and thus improve the mental health of athletes.
Collapse
|
4
|
Moullin JC, Staniland L, Uren H, Nielsen S, Lenton S. Advancing the implementation of take-home naloxone by community pharmacists: Testing the role of COM-B. Drug Alcohol Rev 2024; 43:746-759. [PMID: 38287683 DOI: 10.1111/dar.13805] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Revised: 12/05/2023] [Accepted: 12/08/2023] [Indexed: 01/31/2024]
Abstract
INTRODUCTION Opioid-related overdose fatalities are rising despite the increased accessibility of take-home naloxone (THN). Targeted implementation strategies are needed to improve the distribution of naloxone. This study investigates the effectiveness of a short video targeting pharmacists that addresses implementation barriers. METHODS A pre-post, mixed methods design was adopted to examine the effect of a brief behaviour change intervention (an educational video informed by the capability, opportunity, motivation affecting behaviour (COM-B) model), on factors affecting pharmacists' implementation of THN in Western Australia. Paired samples t-tests for were used to investigate intentions, knowledge, skill, confidence, feasibility, appropriateness, acceptability, attitudes, anticipated patient reactions, social support and implementation climate. Structural equation modelling examined the associations between constructs and to test the proposed mediation of motivation on capability and opportunity affecting intentions to discuss and provide THN. RESULTS We analysed data from 102 participants. At follow-up and after all participants had viewed the video, participants had significantly improved intentions, skill, confidence, anticipated reactions, social support and perceptions that THN implementation was feasible, appropriate and acceptable. No significant differences were seen for attitudes, knowledge or implementation climate. The proposed mediation effect of motivation on the associations between opportunity and intentions and capability and intentions was not supported. DISCUSSION AND CONCLUSIONS A short video directly targeting identified implementation barriers has the ability to improve key influences in the provision of THN. Dissemination of information to community pharmacists is a challenge. Implementation strategies addressing knowledge and targeting other levels of influence on intentions and behaviour are required.
Collapse
|
5
|
Joseph AM, Alsalman RA, Almasoud WA, Almutairi R, Alammari RB, Deeban YAM, Mustafa MZ, Thakare AA. Predicting the employment of teledentistry in clinical practice by the Saudi dental community using a theoretical model. Digit Health 2024; 10:20552076241253739. [PMID: 38736733 PMCID: PMC11085021 DOI: 10.1177/20552076241253739] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/22/2024] [Indexed: 05/14/2024] Open
Abstract
Introduction There are very few scholastic studies applying a theory-driven methodology to analyse the employment of teledentistry in clinical practice by the Saudi dental community. The objective of this research was to predict the employment of teledentistry in clinical practice by the Saudi dental community using the UTAUT (Unified Theory of Acceptance and Use of Technology) model. Methods A countrywide survey was executed from November 2022 to April 2023 among the dental community (pre-graduate students, graduates, post-graduate students, general dentists, and specialist dentists) involved in clinical practice. The survey employed the UTAUT model, which has four fundamental constructs: performance expectancy (PE), effort expectancy (EE), social influence (SI) and facilitating conditions (FC). These constructs are known to impact the user's behavioural intention (BI). The four fundamental constructs were independent, and BI was the dependent variable. A Likert scale with five scores was used to record each variable. Descriptive statistics were used to describe all the constructs. Cronbach's alpha scores were used to measure the inner consistency of the Likert scale. Simple linear regression and multiple linear regression were used to determine the correlation between all the constructs and the overall model's prediction. The Statistical Package for the Social Sciences was applied for analysis. The study had 80% power and an alpha threshold of .05. Results The electronic survey was sent to 3000 participants, out of whom 2143 responded (response rate = 71.43%). PE (R2= 26%, p < .01) was the most significant predictor of the Saudi dental community BI to employ teledentistry in clinical practice, followed by SI (R2= 24%, p < .01), EE (R2= 19%, p < .01) and FC (R2= 6%, p < .01). With statistically significant predictive power, the UTAUT model explained 32% of the variance in the BI (R2= 0.32, p < .01). Conclusions Each UTAUT construct and the entire model were significantly correlated with the employment of teledentistry in clinical practice by the Saudi dental community. PE had the most salient correlation, followed by SI, EE and FC. The participants have perceived the benefits of teledentistry, increasing the future likelihood of its utilisation. The Saudi government could consider the UTAUT constructs to promote teledentistry in tandem with Vision 2030.
Collapse
|
6
|
Khatatbeh H, Al‐Dwaikat T, Rababah J, Oláh A, Pakai A. Paediatric nurses' burnout, quality of life and perceived patient adverse events during the COVID-19 pandemic: Testing an integrated model using structural equation modelling. J Clin Nurs 2024; 33:255-264. [PMID: 34719846 PMCID: PMC8662054 DOI: 10.1111/jocn.16114] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 07/30/2021] [Accepted: 10/14/2021] [Indexed: 12/15/2022]
Abstract
PURPOSE A model was hypothesised by integrating two theoretical models: the compassion satisfaction-compassion fatigue and empowerment models. This study aimed to assess the extent to which this integrated model can explain the relationships between paediatric nurses' burnout quality of life, perceived patient safety and work-related variables during the COVID-19 pandemic. BACKGROUND Nurses' burnout is negatively associated with quality of life (QOL) and positively with patient safety. Several theoretical models were introduced to explain burnout determinants and outcomes such as Golembiewski, Munzenrider and Stevenson model, Leiter and Maslach's process model, and Lee and Ashforth's model. However, few models described burnout in relation to QOL or patient safety. METHODS A sample of 225 paediatric nurses responded to questionnaires about burnout, QOL, adverse events and work-related variables. Compassion satisfaction - compassion fatigue and empowerment models were integrated into a single model and tested using structural equation modelling analysis. This study was prepared and is reported according to the STROBE checklist. RESULTS The final model explained 65% of the variance of burnout and 37% of the variance of QOL. The work-related variables (co-workers' support, job satisfaction, satisfaction with the monthly salary, participation in continuous education and exposure to violence) are predicting paediatric nurses' burnout and quality of life. CONCLUSION The Compassion satisfaction - compassion fatigue -Empowerment integrated model allows for assessing the different paths in the relationship between work-related variables and burnout. RELEVANCE TO CLINICAL PRACTICE These results might be essential for nursing managers to develop strategies that improve nurses' work environment and minimise their burnout during COVID-19 pandemic. These strategies should focus on enhancing co-workers' support, job satisfaction and participation in continuous education. Furthermore, paediatric nurses should be protected from any violence.
Collapse
|
7
|
Su Z, Cheng Y, Liu Z, Zhou J, Li D, Li Y. Experimental Study on Thermal Conductivity of Water-Based Magnetic Fluid Loaded with Different Nanoparticles. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:2952. [PMID: 37999306 PMCID: PMC10675603 DOI: 10.3390/nano13222952] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Revised: 11/08/2023] [Accepted: 11/12/2023] [Indexed: 11/25/2023]
Abstract
Magnetic fluids, a new type of energy transfer fluid with tunable properties, have garnered significant interest from researchers worldwide. Hybrid magnetic fluids prepared by adding different types of nanoparticles exhibit superior thermophysical properties and functional characteristics. In this paper, we prepared a water-based magnetic fluid loaded with multi-walled carbon nanotubes (MCNTs), silver (Ag), and copper (Cu) to enhance thermal conductivity. Using a transient double hot-wire method, we designed and built an experimental measurement system for the thermal conductivity of magnetic fluids with an average measurement error of less than 5%. We studied the thermal conductivity of hybrid magnetic fluids under different conditions and evaluated the advantages and disadvantages of various models, including the Maxwell model, H&C model, Tim model, Y&C model, and Evans model. Our results show that MF+MCNTs, MF+Ag, and MF+Cu nanofluids can all improve the thermal conductivity of the carrier fluid, with MF+MCNTs exhibiting the best improvement effect of 10.93%. Among the five models evaluated, the Evans model had the best predictive effect with a deviation range within 5%. This work provides theoretical and practical reference for enhancing the thermal conductivity of magnetic fluids and provides a more accurate theoretical model for calculating the thermal conductivity of hybrid magnetic fluids.
Collapse
|
8
|
Su P, Han B, Wang Y, Wang H, Gao B, Lu TJ. Crashworthiness of Foam-Filled Cylindrical Sandwich Shells with Corrugated Cores. MATERIALS (BASEL, SWITZERLAND) 2023; 16:6605. [PMID: 37834741 PMCID: PMC10574494 DOI: 10.3390/ma16196605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Revised: 10/05/2023] [Accepted: 10/07/2023] [Indexed: 10/15/2023]
Abstract
Inspired by material hybrid design, novel hybrid sandwich shells were developed by filling a corrugated cylindrical structure with aluminum foam to achieve higher energy absorption performance. The crushing behavior of the foam-filled corrugated sandwich cylindrical shells (FFCSCSs) was investigated using theoretical and numerical methods. Numerical results revealed a significant enhancement in the energy absorption of FFCSCSs under axial compression, showcasing a maximum specific energy absorption of 60 kJ/kg. The coupling strengthening effect is highly pronounced, with a maximum value of F¯c/F¯ reaching up to 40%. The mechanism underlying this phenomenon can be approached from two perspectives. Firstly, the intrusion of folds into the foam insertions allows for more effective foam compression, maximizing its energy absorption capacity. Secondly, foam causes the folds to bend upwards, intensifying the mutual compression between the folds. This coupling mechanism was further investigated with a focus on analyzing the influence of parameters such as the relative density of the foam, the wall thickness of the sandwich shell, and the material properties. Moreover, a theoretical model was developed to accurately predict the mean crushing force of the FFCSCSs. Based on this model, the influence of various variables on the crushing behavior of the structure was thoroughly investigated through parametric studies.
Collapse
|
9
|
Luan L, Dini-Andreote F, Sun B, Jiang Y. Modeling soil bacterial diversity: challenges and opportunities. Trends Microbiol 2023; 31:885-888. [PMID: 37301687 DOI: 10.1016/j.tim.2023.05.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2023] [Revised: 05/23/2023] [Accepted: 05/24/2023] [Indexed: 06/12/2023]
Abstract
Understanding the mechanisms structuring soil bacterial diversity has critical implications to advance the parametrization of species distribution models. This forum article discusses recent advances in the use of the metabolic theory of ecology applicable to soil microbiology, and highlights challenges and opportunities to inform future empirical and theoretical studies.
Collapse
|
10
|
Hu Y, Lin L, Zeng D, Wang Y, Zhang R, Zhang Z, Wang Z, Zhang G, Ye X. Accuracy of the FY-L formula in calculating intraocular lens power after small-incision lenticule extraction. Front Med (Lausanne) 2023; 10:1241824. [PMID: 37692774 PMCID: PMC10483841 DOI: 10.3389/fmed.2023.1241824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2023] [Accepted: 08/01/2023] [Indexed: 09/12/2023] Open
Abstract
Purpose The study aimed to assess the accuracy of the FY-L formula in calculating intraocular lens (IOL) power after small-incision lenticule extraction (SMILE). Methods For the post-SMILE IOL calculation of the same eye, the IOL power targeting the pre-SMILE eyes' lowest myopic refractive error was used. The FY-L formula, the Emmetropia Verifying Optical Formula (EVO-L), the Barrett True-K no history, and the Shammas-L, respectively, were used to calculate the predicted refractive error of target IOL power. A comparison was made between the change in spherical equivalent induced by SMILE (SMILE-Dif) and the variance between IOL-Dif (IOL-Induced Refractive Error) before and after SMILE. The prediction error (PE) was defined as SMILE-Dif minus IOL-Dif. The proportion of eyes with PEs within ±0.25 D, ±0.50 D, ±0.75 D, and ±1.00 D, the numerical and absolute prediction errors (PEs and AEs), and the median absolute error (MedAE) were compared. Results In total, 80 eyes from 42 patients who underwent SMILE were included in the study. The FY-L formula generated the sample's lowest mean PE (0.06 ± 0.76 D), MAE (0.58 ± 0.50 D), and MedAE (0.47 D), respectively. The PEs in ±0.25 D, ±0.50 D, ±0.75 D, and ±1.00 D comprised 28.8%, 46.3%, 70.0%, and 87.5%, respectively, for the FY-L formula. Compared to other formulas, the FY-L formula produced the highest value with PEs for the percentage of eyes in ±0.50 D, ±0.75 D, and ±1.00 D. Conclusion This study demonstrates that the FY-L formula provides satisfactory outcomes in estimating the IOL power in the eyes after SMILE.
Collapse
|
11
|
Ge H, Sun Z, Jiang Y, Wu X, Jia Z, Cui G, Zhang Y. Recent Advances in THz Detection of Water. Int J Mol Sci 2023; 24:10936. [PMID: 37446112 DOI: 10.3390/ijms241310936] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2023] [Revised: 06/19/2023] [Accepted: 06/27/2023] [Indexed: 07/15/2023] Open
Abstract
The frequency range of terahertz waves (THz waves) is between 0.1 and 10 THz and they have properties such as low energy, penetration, transients, and spectral fingerprints, which are especially sensitive to water. Terahertz, as a frontier technology, have great potential in interpreting the structure of water molecules and detecting biological water conditions, and the use of terahertz technology for water detection is currently frontier research, which is of great significance. Firstly, this paper introduces the theory of terahertz technology and summarizes the current terahertz systems used for water detection. Secondly, an overview of theoretical approaches, such as the relaxation model and effective medium theory related to water detection, the relationship between water molecular networks and terahertz spectra, and the research progress of the terahertz detection of water content and water distribution visualization, are elaborated. Finally, the challenge and outlook of applications related to the terahertz wave detection of water are discussed. The purpose of this paper is to explore the research domains on water and its related applications using terahertz technology, as well as provide a reference for innovative applications of terahertz technology in moisture detection.
Collapse
|
12
|
Liu C, Chen N, Xing G, Chen R, Shao T, Shan B, Pan Y, Xu M. A Novel Thermal Tactile Sensor Based on Micro Thermoelectric Generator for Underwater Flow Direction Perception. SENSORS (BASEL, SWITZERLAND) 2023; 23:5375. [PMID: 37420543 DOI: 10.3390/s23125375] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2023] [Revised: 05/30/2023] [Accepted: 06/04/2023] [Indexed: 07/09/2023]
Abstract
Underwater vehicles can operate independently in the exploitation of marine resources. However, water flow disturbance is one of the challenges underwater vehicles must face. The underwater flow direction sensing method is a feasible way to overcome the challenges but faces difficulties such as integrating the existing sensors with underwater vehicles and high-cost maintenance fees. In this research, an underwater flow direction sensing method based on the thermal tactility of the micro thermoelectric generator (MTEG) is proposed, with the theoretical model established. To verify the model, a flow direction sensing prototype is fabricated to carry out experiments under three typical working conditions. The three typical flow direction conditions are: condition No. 1, in which the flow direction is parallel to the x-axis; condition No. 2, in which the flow direction is at an angle of 45° to the x-axis; and condition No. 3, which is a variable flow direction condition based on condition No. 1 and condition No. 2. According to the experimental data, the variations and orders of the prototype output voltages under three conditions fit the theoretical model, which means the prototype can identify the flow direction of three conditions. Besides, experimental data show that in the flow velocity range of 0~5 m/s and the flow direction variation range of 0~90°, the prototype can accurately identify the flow direction in 0~2 s. The first time utilizing MTEG on underwater flow direction perception, the underwater flow direction sensing method proposed in this research is cheaper and easier to be applied on the underwater vehicles than traditional underwater flow direction sensing methods, which means it has great application prospects in underwater vehicles. Besides, the MTEG can utilize the waste heat of the underwater vehicle battery as the energy source to achieve self-powered work, which greatly enhances its practical value.
Collapse
|
13
|
Gao Y, Zhao F, Jiang X, Zhang W. Thermoreversible Tissue Adhesion with Hydrogel Through a Topological Entanglement Approach. Macromol Rapid Commun 2023:e2300144. [PMID: 37221080 DOI: 10.1002/marc.202300144] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 05/06/2023] [Indexed: 05/25/2023]
Abstract
Achieving thermoreversible adhesion between hydrogel and living tissues in a facile way is challenging. Existing strategies bring difficulty to the chemical design and synthesis of hydrogels. Herein, an approach to achieve tough thermoreversible tissue adhesion with hydrogel is proposed, which uses a polymer solution with heat-induced sol-gel transition as the interfacial polymer matrix, with no chemical design required for the hydrogel network. When the interfacial polymer matrix is introduced to the interface of the hydrogel and living tissues, it can gelate in situ within the substrate networks under a temperature stimulus, and topologically entangle with the preexisting networks of the substrates, which generates a strong adhesion. By triggering with another temperature stimulus, the newly formed network dissociates, to realize an easy detachment. Thermoreversible adhesion is demonstrated between polyacrylamide hydrogel and various porcine tissues as examples, and the mechanism of this adhesion strategy is studied by varying various influence factors. A theoretical model that can fit and predict the effects of different parameters on the adhesion energies is also established. This adhesion strategy based on topological entanglement among a thermoreversible polymer system and the substrates may broaden the achieving methods of thermoreversible tissue adhesion. This article is protected by copyright. All rights reserved.
Collapse
|
14
|
Wang H, Lv H, Luo Z. Analysis of Mechanical Properties and Fatigue Life of Microturbine Angular Contact Ball Bearings under Eccentric Load Conditions. SENSORS (BASEL, SWITZERLAND) 2023; 23:s23094503. [PMID: 37177706 PMCID: PMC10181543 DOI: 10.3390/s23094503] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Revised: 04/29/2023] [Accepted: 05/03/2023] [Indexed: 05/15/2023]
Abstract
Angular contact ball bearings are common basic components in rotating machinery. During the operation of the bearing, the rolling slips, resulting in contact sliding friction between it and the raceway, which in turn causes wear in the rolling element and increase in the radial clearance of the bearing. The increase in clearance also affects the stiffness of the bearing, which in turn affects the natural frequency and fatigue life of the bearing. At present, there are few studies on the influence of bearing wear (variation of clearance) on life. In this paper, the finite element model based on the theory of contact mechanics is established for the angular contact ball bearing with medium- and high-speed rotation, and the mechanical properties and fatigue life influenced by the internal action of the bearing are analyzed. The effects of radial load and deflection angle on the mechanical properties and fatigue life of the bearing are also studied. Based on the analysis results of bearing contact mechanical properties and clearance changes, the calculation method of bearing life under rolling element wear is established. The influence of the variation of clearance and preload clearance on bearing life is analyzed, and the optimal preload is obtained. The research results of this paper can provide a theoretical basis for optimizing the installation of angular contact ball bearings, reasonably determining the service conditions, and prolonging the service life of bearings, which is necessary for engineering practice.
Collapse
|
15
|
Singer J, Daum C, Evans A, Schneider S, Vugrin M, Loggers E. An examination and proposed theoretical model of risk and protective factors for bereavement outcomes for family members of individuals who engaged in medical aid in dying: A systematic review. Palliat Med 2023:2692163231172242. [PMID: 37129287 DOI: 10.1177/02692163231172242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
BACKGROUND Medical Aid in Dying is an end-of-life option that allows a physician to provide a patient with a prescription to end their life. Though Medical Aid in Dying intends to reduce suffering for a patient, opponents argue Medical Aid in Dying may increase suffering for the family members during bereavement. To better understand the bereavement outcomes for family members/friends following Medical Aid in Dying, an exhaustive review of the risk and protective factors for bereavement outcomes is warranted. AIM This systemic review aimed to identify studies that examined bereavement outcomes of family members of individuals who engage in Medial Aid in Dying, identify risk and protective factors for bereavement outcomes, and propose a theoretical model to enhance conceptual clarity. DESIGN A mixed-method systematic review. DATA SOURCES Ten databases were searched on June 16, 2021 and later conducted two updates (latest April 25, 2022). RESULTS Thirteen articles met inclusion criteria. Risk and protective factors were identified pre-Medical Aid in Dying and risk factors post-Medical Aid in Dying. Few studies compared bereavement outcomes for family members of individuals utilizing Medical Aid in Dying to family members who lost someone to natural loss. CONCLUSIONS This study provides equivocal results about the effects of Medical Aid in Dying on family members following the loss. The theoretical model outlines potential risk and protective factors. This model provides a greater understanding of possible universal risk and protective factors for family members of individuals who engaged in Medical Aid in Dying.
Collapse
|
16
|
Han B, Song Z, Zhang J, Xie H, Yan W, Liu Y, Yu J. Coupled Effect of Chloride Corrosion and Repeated Uniaxial Compressive Loading on Unsaturated Concrete. MATERIALS (BASEL, SWITZERLAND) 2023; 16:2947. [PMID: 37109783 PMCID: PMC10143740 DOI: 10.3390/ma16082947] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Revised: 03/31/2023] [Accepted: 04/04/2023] [Indexed: 06/19/2023]
Abstract
Concrete structure performance continuously deteriorates during operation, and the performance is simultaneously affected by chloride corrosion and repeated traffic loading. Repeated-loading-induced cracks have an impact on the rate of chloride corrosion. Chloride-induced concrete corrosion also affect the stress level of the structure under loading. Therefore, the coupled effect of repeated loading and chloride corrosion on the structural performance needs to be investigated. An upgraded test device was developed for chloride corrosion testing of unsaturated concrete structures under repeated loading. Based on the experimental results, considering the influence of repeated loading on the moisture diffusion coefficient and the chloride diffusion coefficient, a chloride transport model for unsaturated concrete under the coupled effect of repeated uniaxial compressive loading and corrosion was established. The chloride concentration under coupled loading was determined by the Crank-Nicolson finite difference method and the Thomas algorithm, and then chloride transport under the coupled effect of repeated loading and corrosion was analyzed. The results showed that the stress level and the repeated loading cycles directly affect the relative volumetric water content and chloride concentration in unsaturated concrete. The effect of chloride corrosion is more severe in unsaturated concrete compared to saturated concrete.
Collapse
|
17
|
Lignola GP, Fabbrocino F, Prota A, Cosenza E, Manfredi G. Reinforcement Corrosion in RC Hollow Piers: Destructive and Non-Destructive Tests. MATERIALS (BASEL, SWITZERLAND) 2023; 16:2790. [PMID: 37049086 PMCID: PMC10095726 DOI: 10.3390/ma16072790] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Revised: 03/28/2023] [Accepted: 03/29/2023] [Indexed: 06/19/2023]
Abstract
In this work, cyclic-load tests on reduced-scale corroded reinforced-concrete hollow cross-section bridge piers have been experimentally performed and compared to the results of similar non-corroded piers. Piers were aged by using an imposed electric current and sodium chloride water solution before performing a mechanical cyclic-load test. The corrosion process has been detected with Non-Destructive Evaluation techniques by means of SonReb method (to check concrete degradation) and by measuring corrosion potential (to check steel degradation). The crack pattern was recorded by dedicated cameras, and an LVDT system was set up to monitor the cyclic-load test. Experimental results focused on degradation monitoring and mechanical performance under cyclic loads. During the cyclic-load mechanical test, the first cracks on the piers surface occurred diagonally, inclined at about 45°. This is the consequence of the failure mode change from ductile failure, as expected for slender designed piers, to brittle shear failure. The flexural failure occurred in the case of non-corroded piers. Presented tests can provide a useful contribution of experimental data to analyse the behaviour of corroded reinforced concrete hollow bridge piers, scarcely tested. In particular, the cyclic response can be a useful reference for the proposition/validation of nonlinear capacity models for the evaluation of the seismic capacity of corroded bridge piers.
Collapse
|
18
|
Li CX, Liu X, Gong ZC, Liu H, Jumatai S. Effects of condyle on disc status of the reducing and nonreducing anterior disc displacement of the temporomandibular joint based on 3D reconstructive imaging: a pilot study. QUINTESSENCE INTERNATIONAL (BERLIN, GERMANY : 1985) 2023; 54:156-166. [PMID: 36421045 DOI: 10.3290/j.qi.b3512027] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
OBJECTIVES Morphologic study is a common approach in the field of anterior disc displacement (ADD) pathology; however, analysis based on 3D reconstructive imaging has not been investigated. This study investigated the association between ADD and the status of the mandibular condyle and articular fossa. METHOD AND MATERIALS Thirty-four patients were divided into a normal articular disc position (NADP) group, an ADD with reduction (ADDwR) group, and an ADD without reduction (ADDwoR) group. Images reconstructed were used to determine multiple grouped comparisons of these three different types of disc position, and the diagnostic efficacy for the morphologic parameters with significant grouped difference was analyzed to assess. RESULTS The condylar volume and condylar superficial area of the NADP, ADDwR, and ADDwoR groups exhibited obvious changes (P < .05). A multivariate logistic ordinal regression model showed that the condylar volume (odds ratio [OR], 1.011; regression coefficient [RC] = .011, P = .018), superior joint space (OR, 8.817; RC = 2.177; P < .001), and medial joint space (OR, 1.492; RC = 0.400; P = .047) had a significantly positive impact on the groups. CONCLUSION The mandibular condyle and articular fossa in temporomandibular joint ADD exhibited altered dimensions. The condylar volume, condylar superficial area, superior joint space, and medial joint space could be considered as promising biometric markers for assessing ADD, and were investigated in this current pilot study. (Quintessence Int 2023;54:156-166; doi: 10.3290/j.qi.b3512027).
Collapse
|
19
|
Qiao B, Liang Z, Liang F. Destructive Effect of High-Temperature Heat Flow of Solid Slow-Release Energetic Materials on a Steel Target. MATERIALS (BASEL, SWITZERLAND) 2023; 16:1362. [PMID: 36836992 PMCID: PMC9963872 DOI: 10.3390/ma16041362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 01/31/2023] [Accepted: 02/01/2023] [Indexed: 06/18/2023]
Abstract
To investigate the high-temperature heat flow's destructive effect of solid slow-release energetic materials on a steel target, we prepared a sample of solid slow-release energetic materials, eruption devices, and a complete test system to conduct the destruction of high-temperature heat flow on the steel target. In addition, we proposed the energy density to characterise the high-temperature heat flow performance and numerically simulated the destructive effect of the high-temperature heat flow on the steel target. The numerical simulation results were in good agreement with the test results, and the error between them was under 8.5%. Based on the test and simulation results, the steady-state melting model of the steel target was established under the action of high-temperature heat flow. Moreover, a time-varying model of the melting hole shape was found. The results showed that the model of destroying the steel target with the high-temperature heat flow of solid slow-release energetic materials was highly accurate. Therefore, the model could provide theoretical guidance for designing and applying solid slow-release energetic materials in ammunition destruction, metal cutting, the simulation of the laser thermal effect, etc.
Collapse
|
20
|
Araya-Castillo L, Burgos M, González P, Rivera Y, Barrientos N, Yáñez Jara V, Ganga-Contreras F, Sáez W. Procrastination in University Students: A Proposal of a Theoretical Model. Behav Sci (Basel) 2023; 13:bs13020128. [PMID: 36829358 PMCID: PMC9952811 DOI: 10.3390/bs13020128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 01/19/2023] [Accepted: 01/23/2023] [Indexed: 02/05/2023] Open
Abstract
Procrastination is a phenomenon that affects university students and consists of not finishing a task or finishing it late, which has a direct impact on their academic performance. This is relevant because, in a context of high competition, higher education institutions and their decision-makers need to be aware of the factors that influence university students' procrastination in order to implement actions that favor student attraction and retention. Based on the above, this research aims to propose a theoretical model of procrastination in university students, based on the literature review and content validation assessment through a semi-structured questionnaire. The proposed model is made up of nine dimensions: Psychological, Physiological, Social, Academic, Leisure, Time Management, Resources, Labor, and Environmental. Dimensions were obtained based on adequate levels of content validity provided by the literature and the questionnaire. In the future, the research proposes to study the way in which these dimensions are present in procrastination and design a scale that allows for their measurement.
Collapse
|
21
|
van Buuren CP, van der Steen JT, Olthof-Nefkens M, Bakker C, Koopmans RTCM, Perry M, Kalf JG. The Complexity of Nutritional Problems in Persons with Dementia: Expanding a Theoretical Model. J Alzheimers Dis 2023; 96:183-192. [PMID: 37742638 PMCID: PMC10657712 DOI: 10.3233/jad-230135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/14/2023] [Indexed: 09/26/2023]
Abstract
BACKGROUND Persons with dementia are at risk of developing nutritional problems. Theoretical models on nutritional problems have been developed, but have not been evaluated with healthcare professionals. OBJECTIVE This study aimed to explore the comprehensiveness and applicability of a theoretical model of nutritional problems in persons with dementia for daily nursing home practice. METHODS A qualitative design employing a combined deductive and inductive approach was used. Healthcare professionals were eligible to participate if they 1) had expert knowledge of and experience with nutritional problems related to dementia, and 2) worked in a nursing home affiliated with an academic network covering the east and south of the Netherlands. Three focus group interviews with 20 healthcare professionals from seven professions were held. We conducted thematic analysis and we compared themes with existing theoretical models from the literature. RESULTS We identified six themes, four of which corresponded with the existing models (observing and analysing nutritional problems; consequences of nutritional problems; functioning of the person with dementia; environmental factors). Interprofessional collaboration and ethical factors were identified as new themes. The analyses indicated interactions within each theme, between themes, and a bidirectional connection between themes. CONCLUSIONS This study demonstrated the relevance of interprofessional collaboration and ethical considerations in nutritional problems related to dementia. It uncovered complex bidirectional relations within and between factors regarding nutritional problems. All aspects should be taken into account to minimize the consequences of nutritional problems for persons with dementia.
Collapse
|
22
|
Gong C, Chen F, Kang C. Theoretical and experimental studies on the oil-based emulsion spray. FRONTIERS IN PLANT SCIENCE 2023; 14:1164200. [PMID: 37152159 PMCID: PMC10154600 DOI: 10.3389/fpls.2023.1164200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/12/2023] [Accepted: 03/27/2023] [Indexed: 05/09/2023]
Abstract
Oil-based emulsion is a common herbicide formulation in agricultural spray, and its atomization mechanism is different from that of water spray. In this paper, a theoretical model based on the characteristics of spray sheets was proposed to predict the spray droplet size for oil-based emulsion spray. An image processing method was used to measure droplet size distributions for different spray pressures and nozzle configurations, and the measured results were used to validate the theoretical model. The results show that oil-based emulsion spray is characterized by the web structure constituted by perforations. The liquid originally occupied by spray sheets eventually gathers in these web structures. The proposed theoretical model is based on the size of the nozzle exit, the angle of spray sheets, and the perforation number in the web structure, which are relatively easy to obtain. The theoretical droplet size is in inverse proportion to the square root of the perforation number in the web structure while in proportion to the square root of the area of the nozzle exit. The captured images of spray sheets and the measured droplet size distribution show consistency with the theoretical prediction. The difference between theoretical results and measured volumetric median diameter is less than 10% for different spray pressures and nozzles.
Collapse
|
23
|
Nogueira D. Nutrition in People with Dementia: What We Know and What We Need to Know to Upskill Those Who Care. J Alzheimers Dis 2023; 96:193-195. [PMID: 37781811 DOI: 10.3233/jad-230970] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/03/2023]
Abstract
Feeding and swallowing difficulties and their consequences on the nutritional status of people with dementia have been the subject of recurrent research, albeit strong evidence is still lacking. When a person no longer swallows safely, it is the caregivers who face difficulties of providing adequate care. Therefore, it is important to understand and analyze their perspectives on the topic. Despite the recent development of theoretical models to manage mealtimes and nutrition intake, the participation of health professionals and caregivers in these types of studies are still limited. The study of van Buuren et al., which this commentary refers to, aimed to identify key factors that contribute to the development of a conceptual model to step up nutritional care in dementia.
Collapse
|
24
|
Acquired von Willebrand syndrome in patients with monoclonal gammopathy of undetermined significance investigated using a mechanistic approach. BLOOD TRANSFUSION = TRASFUSIONE DEL SANGUE 2023; 21:74-82. [PMID: 34694218 PMCID: PMC9918387 DOI: 10.2450/2021.0121-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Accepted: 07/06/2021] [Indexed: 11/21/2022]
Abstract
BACKGROUND Acquired von Willebrand syndrome (AVWS) has been reported to occur in association with monoclonal gammopathy, usually of undetermined significance (MGUS). It may present as a type 1 or type 2 von Willebrand factor (VWF) defect depending on the patient's representation of large VWF multimers. MATERIALS AND METHODS The mathematical model by Galvanin et al., already employed for studying inherited von Willebrand disease (VWD), was used to explore the pathogenic mechanisms behind MGUS-associated AVWS. RESULTS The patients studied showed significantly reduced VWF levels and function; an increased VWF propeptide to VWF antigen ratio; and all VWF multimers present but in reduced quantities, with the low-molecular-weight VWF forms being significantly more represented than those of higher molecular weight. Our mathematical model revealed a significantly increased VWF elimination rate constant, with values similar to those of type Vicenza VWD. An even more increased VWF proteolysis rate constant was observed, with values one order of magnitude higher than in type 2A VWD but, in contrast, no loss of large multimers. The model predicted the same elimination rate for high- and low-molecular-weight VWF multimers, but proteolysis of the high-molecular-weight forms also contributes to the pool of low-molecular-weight oligomers, which explains why they were relatively over-represented. DISCUSSION In MGUS-associated AVWS the increase of both clearance and proteolysis contributes to the circulating levels and multimer pattern of VWF, with a phenotype that appears to be a combination of type Vicenza and type 2A VWD. Hence, the mechanisms behind the onset of AVWS seem to differ from those of inherited VWD.
Collapse
|
25
|
Yang X, Crehan ET. Understanding the experiences and needs in autism education: A semi-structured interview among Chinese American parents of autistic children. AUTISM & DEVELOPMENTAL LANGUAGE IMPAIRMENTS 2023; 8:23969415231217191. [PMID: 38045606 PMCID: PMC10693210 DOI: 10.1177/23969415231217191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/05/2023]
Abstract
Background and Aims The diversity of the autistic population seeking professional services and education in the United States has increased. As the diagnosis of autism increases among the Chinese American immigrant population, there is also an increasing need to learn about this population and provide appropriate intervention and education for this group. However, current education and intervention provided for autistic individuals tend to be culturally blind. Gaps were found in our understanding of the cultural context and its relationship with the education mechanisms among Chinese American autistic families. The current study intends to investigate how Chinese American parents perceive the education materials and intervention strategies received by their autistic children as well as their experiences and needs in the education process. Method Semi-structured interviews were conducted among 10 Chinese American parents (one father and nine mothers) online. They all had children who had a formal diagnosis of autism spectrum disorder and received some intervention or education. Thematic analysis was used to analyse the results. Results The study suggested that most Chinese American parents were satisfied with the current education materials and intervention strategies provided to their autistic children. Due to cultural-related stigma, parents differ in their perceptions of children's autism diagnosis and characteristics as well as their expectations of children's culturally sensitive education. A theoretical model was created to provide culture-centered interpretation of the interconnected relationship between their pre- and post-immigration contexts and parenting attitudes. Conclusions Culture plays a critical role in understanding Chinese American parents' experiences, needs, and expectations of culturally sensitive education for their autistic children. Interconnected relationships were found between contexts and parenting attitudes, which were largely influenced by cultural-related stigma. Implications Suggestions and implications were provided for institutions and professionals working with Chinese American families and children. It is critical for them to learn about the experiences, needs, and attitudes of Chinese American parents to provide Chinese American autistic children with more appropriate and culturally sensitive education.
Collapse
|