The selection of biomaterials for bearing in total hip arthroplasty is very important to avoid various risks of primary postoperative failure for patients. The current investigation attempts to ...analyze the Tresca stress of metal-on-metal bearings with three different materials, namely, cobalt chromium molybdenum (CoCrMo), stainless steel 316L (SS 316L), and titanium alloy (Ti6Al4V). We used computational simulations using a 2D axisymmetric finite element model to predict Tresca stresses under physiological conditions of the human hip joint during normal walking. The simulation results show that Ti6Al4V-on-Ti6Al4V has the best performance to reduce Tresca stress by 45.76% and 39.15%, respectively, compared to CoCrMo-on-CoCrMo and SS 316L-on-SS 316L.
Hip joint prostheses are used to replace hip joint function in the human body. The latest dual-mobility hip joint prosthesis has an additional component of an outer liner that acts as a cover for the ...liner component. Research on the contact pressure generated on the latest model of a dual-mobility hip joint prosthesis under a gait cycle has never been done before. The model is made of ultrahigh molecular weight polyethylene (UHMWPE) on the inner liner and 316L stainless steel (SS 316L) on the outer liner and acetabular cup. Simulation modeling using the finite element method is considered static loading with an implicit solver for studying the geometric parameter design of dual-mobility hip joint prostheses. In this study, simulation modeling was carried out by applying varying inclination angles of 30°, 40°, 45°, 50°, 60°, and 70° to the acetabular cup component. Three-dimensional loads were placed on femoral head reference points with variations of femoral head diameter used at 22 mm, 28 mm, and 32 mm. The results in the inner surface of the inner liner, the outer surface of the outer liner, and the inner surface of the acetabular cup showed that the variations in inclination angle do not have a major effect on the maximum contact pressure value on the liner component, where the acetabular cup with an inclination angle of 45° can reduce contact pressure more than the other studied inclination angle variations. In addition, it was found that the 22 mm diameter of the femoral head increases the contact pressure. The use of a larger diameter femoral head with an acetabular cup configuration at a 45° inclination can minimize the risk of implant failure due to wear.
Bearing on artificial hip joint experiences friction, wear, and surface damage that impact on overall performance and leading to failure at a particular time due to continuous contact that endangers ...the user. Assessing bearing hip joint using clinical study, experimental testing, and mathematical formula approach is challenging because there are some obstacles from each approach. Computational simulation is an effective alternative approach that is affordable, relatively fast, and more accessible than other approaches in examining various complex conditions requiring extensive resources and several different parameters. In particular, different gait cycles affect the sliding distance and distribution of gait loading acting on the joints. Appropriate selection and addition of gait cycles in computation modelling are crucial for accurate and reliable prediction and analysis of bearing performance such as wear a failure of implants. However, a wide spread of gait cycles and loading data are being considered and studied by researchers as reported in literature. The current article describes a comprehensive literature review adopted walking condition that has been carried out to study bearing using computational simulation approach over the past 30 years. Many knowledge gaps related to adoption procedures, simplification, and future research have been identified to obtain bearing analysis results with more realistic computational simulation approach according to physiological human hip joints.
Computational simulation; Human hip joint; Hip joint prosthesis; Hip resurfacing; Total hip arthroplasty; Walking condition.
Fragile X syndrome (FXS) is caused by a full mutation of the FMR1 gene (>200 CGG repeats and subsequent methylation), such that there is little or no FMR1 protein (FMRP) produced, leading to ...intellectual disability (ID). Individuals with the premutation allele (55-200 CGG repeats, generally unmethylated) have elevated FMR1 mRNA levels, a consequence of enhanced transcription, resulting in neuronal toxicity and a spectrum of premutation-associated disorders, including the neurodegenerative disorder fragile X-associated tremor/ataxia syndrome (FXTAS). Here we described 14 patients who had both lowered FMRP and elevated FMR1 mRNA levels, representing dual mechanisms of clinical involvement, which may combine features of both FXS and FXTAS. In addition, the majority of these cases show psychiatric symptoms, including bipolar disorder, and/or psychotic features, which are rarely seen in those with just FXS.
Traveling with children with autism can be very challenging for parents due to their reactions to sensory stimuli resulting in behavioral problems, which lead to self-injury and danger for themselves ...and others. Deep pressure was reported to have a calming effect on people with autism. This study was designed to investigate the physiological effect of deep pressure, which is an autism hug machine portable seat (AHMPS) in children with autism spectrum disorders (ASD) in public transportation settings. The study was conducted with 20 children with ASD (16 boys and 4 girls) at the Semarang Public Special School with an age ranging from 4 to 13 years (mean 10.9 ± 2.26 years), who were randomly assigned into two groups. The experiment consisted of group I who used the AHMPS inflatable wraps model and group II who used the AHMPS manual pull model. Heart rate (HR) and skin conductance (SC) were analyzed to measure the physiological calming effect using pulse oximeter oximetry and a galvanic skin response (GSR) sensor. Heart rate was significantly decreased during the treatment compared to the baseline (pre-test) session in group I (inflating wrap model) with p = 0.019, while no change of heart rate variability (HRV) was found in group II (manual pull model) with p = 0.111. There was no remaining effect of deep pressure using the HRV indicator after the treatment in both groups (group I with p = 0.159 and group II with p = 0.566). GSR captured the significant decrease in skin conductance during the treatment with p < 0.0001 in group I, but no significant decrease was recorded in group II with p = 0.062. A skin conductance indicator captured the remaining effect of deep pressure (after the treatment); it was better in group I (p = 0.003) than in group II (p = 0.773). In conclusion, the deep pressure of the AHMPS inflating wrap decreases physiological arousal in children with ASD during traveling.
Abstract
Background
There is a lack of genetic knowledge among health care professionals especially in some developing countries such as Indonesia. Based on our experience, genetic disorders receive ...less attention in medical education and professionals. This study aims to determine the familiarity and literacy of genetics among medical students in Indonesia.
Methods
A total of 1003 Indonesian medical (pre-clinical and clinical) students completed the Rapid Estimate of Adult Literacy in Genetics (REAL-G) questionnaire with a total score of seven for familiarity and eight for genetic literacy. The Mann-Whitney U test was used to compare the familiarity and genetic literacy scores between pre-clinical and clinical students.
Results
The average scores of familiarity and genetic literacy were 5.63
±
0.96 and 6.37
±
0.83, respectively. Genetic familiarity was higher (
p
= 0.043) among clinical students than pre-clinical students, while there was no significant difference in genetic literacy (
p
= 0.362) between pre-clinical and clinical students. Genetic familiarity does not impact the level of genetic literacy. However, medical students’ genetic literacy is influenced by demographic characteristics, such as age, sex, university type, genetic learning experience, university accreditation, and university location.
Conclusions
In general, Indonesian medical students have relatively good familiarity and literacy in genetics although further study is necessary to accurately measure the genetic familiarity and literacy in medical students and general public.
Background: Obesity has been associated with the risk of various diseases. The correlation between anthropometry and bone health is complex. Visceral adipocyte index (VAI) is one of the compositions ...of body fat compositions that mostly associated with proinflammatory cytokine, which can stimulate C- reactive protein (CRP) that affects bone density.Objectives: This study aimed to prove the correlation between VAI, CRP and BMD in Asian reproductive obese womenMaterials and Methods: A cross sectional study was conducted in November 2020 - February 2021 and a total of 134 women of reproductive age with obesity participated in this study. Weight, height, body mass index (BMI) and rate of visceral fat were measured by body composition analyzer. Waist (WC) and hip circumferences (HC) measured by using tape; lipid profile and CRP level were examined using a clinical chemistry automatic analyzer, and the examination of bone mineral density (BMD) using dual-energy x-ray absorptiometry. Waist to hip ratio (WHR)and VAI calculated manually. Pearson and Spearman test were used for statistical analysis.Results: There were positive weak correlations between weight, height, BMI, WC, HC, rate of visceral fat, WHR and VAI. There were weak positive correlations between HC, WHR and CRP. There were positive moderate correlations between weight, height, BMI, waist, visceral fat, WHR and CRP. Conclusion: Although there were correlations between anthropometric parameters and VAI and also CRP, but we did not found correlation between VAI and CRP to all BMD parameters.
AbstractObjectives: This study aimed to evaluate the subjective acceptability and physiological response of an inflatable vest as a wearable device to stimulate calming effects. Methods: A Visual ...Analogue Scale (VAS) was used as a subjective measurement and an electroencephalogram (EEG) as an objective/physiological measurement. Results: The results showed that the subjective scores of 30 male participants rated the prototype as an ‘excellent’ device, with an average score of 81. An increase in the theta (4–8 Hz) frequency band was the most noticeable change in EEG, which represented the calming effect behavior experienced in 64% of all participants. Conclusion: The self-regulated inflatable vest could be beneficial for therapeutic purposes by inducing a calming effect.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Children with autism spectrum disorder (ASD) have challenging behaviors, which are associated with difficulties in parenting. Deep pressure is a therapeutic modality in occupational therapy, and it ...was reported to produce a calming effect. This study aimed to determine whether the short-term use of an autism hug machine portable seat (AHMPS) improves behavioral and neurobiological stress in children with ASD, and to determine whether AHMPS with an inflatable wrap or manual pull is more effective. This study enrolled children with ASD who were administered with the inflatable wrap (group I) and manual pull (group II) for 20 min twice a week for 3 weeks. Conners' Parent Rating Scale-48 (CPRS-48) was used to rate behavioral improvements, and galvanic skin response (GSR) was used to measure sympathetic stress response. A total of 20 children with ASD (14 boys and 6 girls; aged 7-13 years) were included. CPRS-48 presented conduct problems: behavior was significantly decreased in the inflatable group (
= 0.007) compared to the manual pull group. The GSR captured a significant reduction in sympathetic response (
= 0.01) only in group I. Neurobiological stress was reduced in children who were wearing the AHMPS inflatable wrap; therefore, AHMPS inflatable wrap is an effective method to reduce emotional arousal.
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