A study on thermal behaviour of thermal barrier coating: investigation of particle size, YSZ/polysilazane, time and temperature curing effect.

Thermal conductivity and adhesion strength effects were studied for thermal barrier coatings (TBCs) with different particle sizes, YSZ content, time, and temperature curing. The study involves three stages. The first step focuses on the characteristics of YSZ/polysilazane as the TBC, which is characterized using Scanning Electron Microscopy (SEM), Fourier Transform Infrared (FTIR), X-Ray Diffraction (XRD), and Thermal Gravimetric Analysis (TGA). The second and third steps assess thermal conductivity and adhesion strength based on variables such as particle size, YSZ/polysilazane, time, and curing temperature. Results show that there was a synergistic effect between particle size-YSZ content and time-temperature curing to obtain specimens with good thermal properties. SB270/70 showed the lowest temperature compared to other specimens, up to 160 °C. Furthermore, YSZ/polysilazane thermal conductivity and adhesion properties could be enhanced by a prolonged curing time and higher temperature. This study emphasizes that the modification of particle size, YSZ content, time, and temperature curing is a promising strategy to improve the thermal properties of TBCs.

Morphological and mechanical studies of Al2O3-Na2SiO3 as a skin barrier coated with TiO2 for carbon fiber reinforced composite materials.

The utilization of adhesive compounds in bonding lightweight and high-performance composite structures, including carbon fiber reinforced polymer (CFRP) composites, has garnered significant attention from researchers. This study presents the novel application of Al2O3 coated with TiO2 as a thermal protective layer for CFRP substrate. Initially, the CFRP substrate underwent a protective treatment involving the application of Al2O3 as a middle coat, followed by a further protective layer consisting of TiO2 as a top coat. The deposition of TiO2 onto an Al2O3-based thermal barrier coating (TBC) was carried out utilizing the flame spray method. The use of a TiO2 coating as a top coat was employed to enhance protection and heat dispersion across the middle coat and substrate. In order to achieve sufficient adhesion between the CFRP substrate, an intermediate coat consisting of Al2O3 with a Na2SiO3 binder, the impact of varying nozzle distances on adhesion strength and pull-off test outcomes was investigated, with a nozzle distance of 180 mm yielding the highest adhesion strength. The thermal stability of a CFRP substrate was enhanced through the deposition of a layer of TiO2 on Al2O3. The surface and cross-sectional morphologies of the composite were analyzed using a Scanning Electron Microscope (SEM). It was observed that the presence of a TBC on the composite surface effectively reduced the amount of heat that was transferred to the composite material. In order to assess the effectiveness of TBC on CFRP substrates, a series of experiments involving thermal torch and conductivity tests were undertaken. The interaction between the top and middle coats of a composite material results in enhanced mechanical properties, hence improving its thermal insulation capabilities. The artificially produced TBC coatings have the potential to function as adhesive materials, ensuring the sustained high performance of CFRP substrates.

Randomised Clinical Trial Study: The Combination of Vitamin D and Curcumin Piperine Attenuates Disease Activity and Pro-inflammatory Cytokines Levels Insystemic Lupus Erythematosus Patients.

BACKGROUND: Curcumin-piperine might synergise with vitamin D to induce clinical remission in patients with systemic lupus erythematosus (SLE). OBJECTIVE: To observe the improvement of patients with SLE clinically and the levels of inflammatory cytokines after receiving supplements of curcumin-piperine and cholecalciferol (Vitamin D3). METHODS: Forty-five female SLE patients were included in a three-month double-blind, randomized controlled trial. Participants were classified into: Group I (400 IU cholecalciferol + placebo three times daily, n = 15), Group II (600 mg curcumin + 15,800 m piperine once daily and three times daily placebo, n = 15), and Group III (cholecalciferol 400 IU three times and 600 mg curcumin + 15,800 mg piperine once a day, n = 15). Mexican SLE disease activity score (Mex- SLEDAI), fatigue severity scale (FSS), TGF-ß, and IL-6 levels were measured from all patients before and after the treatments. RESULTS: Mex-SLEDAI, FSS, and IL-6 were reduced significantly, while TGF-ß serum levels were increased in all groups after the treatments (p <0.05). Changes in Mex-SLEDAI score (p = 0.003 and p = 0.008), FSS (p = 0.001 and p <0.001), and TGF-ß (p = 0.003 and p = 0.004) serum levels were significantly higher in group III compared to the group I or group II. On the other hand, changes in Mex-SLEDAI, FSS, IL-6, and TGF-ß serum levels were similar between groups I and II. CONCLUSION: Although vitamin D or curcumin-piperine alone could improve the clinical outcome and cytokines levels in SLE, curcumin-piperine combined with vitamin D had the best outcome in improving the disease activity and cytokines levels among patients with SLE. (ClinicalTrials.gov number, NCT05430087).

Non-syndromic Parachute Mitral Valve "When the Valve Dives in": Case Report and Review of the Literature.

A parachute mitral valve (PMV) is a congenital mitral valve anomaly diagnosed in infancy, and it can also be discovered in adults during echocardiography. Surgical management is common in infants to prevent complications from left-heart obstructions. In adults, PMV may be found independently or with other cardiac defects. Prophylactic antibiotics are recommended for certain congenital heart anomalies before dental procedures. A study suggests reconsidering guidelines to include anomalies like bicuspid aortic valve and MVP for antibiotic prophylaxis. PMV, with transvalvular blood flow turbulence, may increase the risk of infective endocarditis, as seen in a reported case with a parachute-like mitral valve. Here, we present the case of a 62-year-old female incidentally found to have a PMV during an echocardiogram.

UTI-Associated Septic Cardiomyopathy: Saving the Heart in the Nick of Time.

A patient with gram-negative sepsis developed acute global biventricular dysfunction with reduced left ventricular ejection fraction. A diagnosis of sepsis-induced cardiomyopathy (SICM) was made following the complete resolution of cardiac dysfunction. This case highlights the importance of the early diagnosis of SICM and treatment of the underlying cause.

To Develop Indonesian Version of The Influence on Physical Activity Instrument for Community-Based Obese Adults: Cross-Cultural Validation and Psychometric Testing.

PURPOSE: Insufficient physical activity is a public health concern in Indonesia, but there are no valid Indonesian tools for exploring the influences. Due to cultural and contextual differences, the Indonesian version of the Influence on Physical Activity Instrument (IPAI-I) was developed and tested the psychometric properties in community obese-adults. METHODS: The cross-sectional study enrolled 846 obese-adults in Indonesian community health-centre. The IPAI was translated with culturally appropriate Indonesian. Using Exploratory Factor Analysis (EFA) and Confirmatory Factor Analysis (CFA) assessed the psychometric properties. The scale reliability was tested by Cronbach's α for internal consistency and intra-class correlation coefficient (ICC) for stability. RESULTS: Through EFA via Principal Axis Factoring with Oblimin rotation, the 21-item IPAI-I exhibited cross-cultural appropriateness, readability with three factors in the individual domain, one factor in the support domain, and two factors in the environment domain. The indices of good fit model for three domains testing by a second-order CFA was achieved at χ2/df=1.5, goodness of fit index = .93, root mean square error of approximation = .039 (p < .001). Furthermore, a high correlation (r = .52; p < .001) was between the support domain and the environment domain, but the two domains had a very low correlation with the individual domain, respectively. The test-retest reliability was by ICC with .73 - .92 and Cronbach's α with .82 - .91 among six-factor, respectively. CONCLUSIONS: The IPAI-I is a valid, reliable instrument to assess in Indonesian context. Enhancing ecological effects are high-priority to increase physical activity for community obese-individual.

Isolated Native Tricuspid Valve Endocarditis in an HIV Patient due to Streptococcus Pneumoniae: A Rare Clinical Phenomenon.

Streptococcus pneumonia is an important cause of septicemia. Other sites of infection include meningitis, septic arthritis, and endocarditis. Pneumococcal endocarditis is rare and has a poor prognosis. We report a case of a 47-year-old female patient with HIV who developed isolated native tricuspid valve endocarditis secondary to streptococcus pneumonia, which is considered to be a very rare presentation in our patient due to the absence of common risk factors such as intravenous drug use, heart disease, or right heart catheterization.

The Indonesian Version of the Exercise Self-Efficacy Scale: Cross-cultural Adaptation and Psychometric Testing.

PURPOSES: The study aimed to translate the Exercise Self-Efficacy Scale (ESES) into Indonesian and test the cultural equivalence, reliability, and validity of the new version for university students. METHODS: The cross-sectional study recruited 379 Indonesian university students using convenience sampling. Phase 1, a culturally appropriate version of the ESES was developed in the Indonesian language. Phase 2, the psychometric properties were determined through exploratory factor analysis, bootstrap factor analysis, and confirmatory factor analysis. The internal consistency reliability was tested using Cronbach's α, whereas the stability using intraclass correlation coefficient to assess. RESULTS: The students' ages ranged from 17 to 39 years, and 65.0% were women. For translation equivalence, the mean item content validity indexes ranged from 3.5 to 4, and all items were understandable. The 16-item scale exhibited cross-cultural appropriateness and readability, with a three-factor model explaining 62.3% of the variance in exercise self-efficacy. A bootstrap analysis using 100 resamples further confirmed the three-factor model. The indices of the good-fit model that used the three-factor by two-stage least squares method were satisfactory, with χ2/df = 3.3, goodness of fit index = .88, and root mean-square error of approximation = .05 (p < .001). The Cronbach's α was .78, .80, and .92 for factors 1, 2, and 3, respectively. The test--retest reliability was demonstrated with an intraclass correlation coefficient of .91, indicating adequate measurement stability. CONCLUSION: The 16-item ESES-I has acceptable validity and reliability; however, a broader application of the scale requires further testing in different populations to confirm its external validity.

"Major" Depressive Disorder, coronary heart disease, and the DSM-IV threshold problem.

Seventy-seven patients with documented coronary heart disease (CHD) were evaluated for demographic/risk factor characteristics, Major Depressive Disorder (MDD) according to the Patient's Health Questionnaire (PHQ - Diagnostic and Statistical Manual IV criteria), and emotional distress by the Symptom Checklist 90-Revised (SCL-90-R). Early age at initial diagnosis for coronary heart disease (AAID) was used as a proxy for disease malignancy because early AAID is a known predictor of early mortality. MDD was unrelated to early AAID despite being strongly associated with all the scales of the SCL-90-R. Several of the SCL-90-R scales were significantly associated with early AAID in the sample as a whole (Depression, Interpersonal Sensitivity, Anxiety, Paranoia, and Psychoticism) and after removal of the patients meeting criteria for MDD (residual N = 54). Our results suggest a new criterion for determining whether depression, or any mental disorder, is "major": onset or aggravation of serious medical illness.

Familial transmissability of early age at initial diagnosis in coronary heart disease (CHD): males only, and mediated by psychosocial/emotional distress?

In equal sized samples, a strong association between a positive Family History of Early Coronary Heart Disease (FamHx) and early Age at Initial Diagnosis (AAID) was found only for males, and thus all further analyses were restricted to males. All three scales of the self-report version of the Ketterer Stress Symptom Frequency Checklist--Revised (KSSFCR)--"AIAI" (or aggravation, irritation, anger, and impatience), Depression, and Anxiety--were associated with both a positive FamHx and early AAID. A series of regression models was used to demonstrate that the KSSFCR scales may plausibly account for 22-32% of the variance in the relationship between a positive FamHx and early AAID. Because of previously documented denial in males, the analyses were repeated in a subgroup of males for whom Spouse/Friend KSSFCRs were obtained. Spouse/Friend-reported AIAI was related to both early FamHx and early AAID, and could account for 68% of the common variance.