Fatigue Reliability Characterisation of Effective Strain Damage Model Using Extreme Value Distribution for Road Load Conditions

The aim of this paper is to characterise the fatigue reliability for various random strain loads under extreme value distribution while considering the cycle sequence effect condition in fatigue life prediction. The established strain–life models, i.e., Morrow and Smith–Watson–Topper, considered a mean stress effect and strain amplitude; nevertheless, it excluded the load sequence effect, which involves the fatigue crack closure that is subjected to overload or underload. A FESEM-EDX analysis is conducted to characterise the failure features that occurred on the leaf spring. A finite element is simulated to determine the critical region in order to obtain the strain load behaviour. In addition, the strain signal is captured experimentally at 500 Hz for 100 s under operating conditions for three different road loads based on the critical location obtained from the finite element analysis. The fatigue life correlation shows that the Pearson correlation coefficients are greater than 0.9, which indicates the effective strain damage model is linearly correlated with the strain–life models. The fatigue life data are modelled using extreme value distribution by considering the random strain loads as extreme data. The reliability rate for the fatigue life is reported to be more than 0.59 within the hazard rate range of 9.6 × 10⁻⁸ to 1.2 × 10⁻⁷ based on the mean cycle to the failure point. Hence, the effective strain damage model is proposed for a fatigue reliability assessment under extreme conditions with higher reliability and provides fatigue life prediction when subjected to cycle sequence effects.     

Factors determining recovery during nutritional therapy of persistent diarrhoea: the impact of diarrhoea severity and intercurrent infections

Abstract The recovery pattern and outcome were analysed in 261 consecutive children (age 6–36 months) with persistent diarrhoea who underwent inpatient nutritional rehabilitation with a rice-lentil (Khitchri) and yoghurt-based diet. Overall. 217 (83%) recovered successfully, as judged by a reduction in stool output and weight gain for a consecutive 3 d. Failures were more commonly febrile at admission [odds ratio (OR) 2.3, 95% confidence interval (CI) 1.1–4.8] and a greater number had culture-proven sepsis (Fisher's exact test, p < 0.001). Logistic regression analysis identified significantly increased risk of treatment failure with several admission characteristics, including stool frequency > 5 d^-1 (OR 2.9, 95% CI 1.6-5.2), vomiting (OR 2.5, 95% CI 1.1–5.7) and sepsis (OR 2.8, 95% CI 1.1–7.5). Survival analysis revealed significantly longer time-to-recovery among children with stool frequency > 5 d^-1 at admission ( p < 0.001), suspected sepsis necessitating intravenous antibiotics ( p < 0.001) or oral candidiasis ( p < 0.05). These findings suggest that severity of diarrhoea and coexisting systemic infections are key determinants of the response to nutritional therapy in children with persistent diarrhoea.     

Effect of electrophilic and nucleophilic substituents on the protonation microequilibria of tyrosine derivatives

The microscopic protonation constants of 10 tyrosine-like, unusual amino acids used in the syntheses of opioid peptides have been determined by using a combined pH-metric-spectrophotometric method, at 0.10 mol dm ^?3 (NaCl) ionic strength and 25.0°. The role of the different electrophilic and nucleophilic substituents on the individual basicity of the aliphatic amine and phenolic hydroxylate basic centers is discussed in detail. The interactivity parameters between these two groups correlate fairly well with the structure of the skeleton and the distance between the two basic centers, but they were found to be substituent-independent. This finding made it possible to extend the calculations to compounds having non-overlapping protonation equilibria.     

Controlled release of a plant growth regulator, alpha-naphthaleneacetate from the lamella of Zn-Al-layered double hydroxide nanocomposite.

Formation of the so-called organic-inorganic nanohybrid material was exploited for the preparation of a controlled release formulation. The inorganic Zn-Al-layered double hydroxide (LDH) was used as a matrix, hosting an active agent or a guest, alpha-naphthaleneacetate (NAA), a plant growth regulator by self-assembly technique. The reverse process, i.e., the deintercalation or release of the guest, NAA was found to be rapid initially, followed by a more sustained release thereafter and this behavior was dependent on the pH of the release medium, the aqueous solution. The mechanism of release has been interpreted on the basis of the ion-exchange process between the NAA anion intercalated in the lamella host and nitrate or hydroxyl anions in the aqueous solution.     

Chest wall resection and reconstruction: a case series of 20 patients in Hospital Kuala Lumpur,Malaysia

Chest wall resection is defined as partial or full-thickness removal of the chest wall. Significant morbidity has been recorded, with documented respiratory failure as high as 27%. Medical records of all patients who had undergone chest wall resection and reconstruction were reviewed. Patients’ demographics, length of surgery, reconstruction method, size of tumor and chest wall defect, histopathological result, complications, duration of post-operative antibiotics, and hospital stay were assessed. From 1 April 2017 to 30 April 2019, a total of 20 patients underwent chest wall reconstructive surgery. The median age was 57 years, with 12 females and 8 males. Fourteen patients (70%) had malignant disease and 6 patients (30%) had benign disease. Nine patients underwent rigid reconstruction (titanium mesh for sternum and titanium plates for ribs), 6 patients had non-rigid reconstruction (with polypropylene or composite mesh), and 5 patients had primary closure. Nine patients (45%) required closure with myocutaneous flap. Complications were noted in 70% of patients. Patients who underwent primary closure had minor complications. In total, 66.7% of patients who had closure with either fasciocutaneous or myocutaneous flaps had threatened flap necrosis. Two patients developed pneumonia and 3 patients (15%) had respiratory failure requiring tracheostomy and prolonged ventilation. There was 1 mortality (5%) in this series. In conclusion, chest wall resections involving large defects require prudent clinical judgment and multidisciplinary assessments in determining the choice of chest wall reconstruction to improve outcomes.     

Retrospective analysis of the sonographic and computed tomographic features of gallbladder empyema

Emergency Radiology - Early detection of complicated cholecystitis, particularly gallbladder empyema, is important. Yet only a handful of patients are correctly diagnosed prior to intervention. The...     

The antimicrobial and antibiofilm properties of allicin against Candida albicans and Staphylococcus aureus – A therapeutic potential for denture stomatitis

The objective of this study is to determine the therapeutic efficacy of allicin against Candida albicans (C. albicans) and Staphylococcus aureus (S. aureus), the common etiological agents for denture stomatitis (DS). The minimum inhibitory concentration (MICs), minimum bactericidal concentrations (MBCs) and minimum fungicidal concentration (MFCs) of allicin were determined by the broth microdilution method followed by checkerboard microdilution method for a synergistic interaction between allicin + nystatin and allicin + CHX. The potential of allicin to eradicate C. albicans and S. aureus biofilms was assessed by treating biofilm formed on self- polymerized acrylic resin with allicin at a sub-MIC concentration for 5 min. The commercial denture cleanser (brand X) was used as a positive control. A Kruskal-Wallis test followed by the post-hoc Mann-Whitney U test was applied (SPSS 20.0), and the level of significance was set at P < 0.05. Allicin exhibited antimicrobial activity against C. albicans (MIC:8 µg/ml and MFC:16 µg/ml) and S. aureus (MIC:8 µg/ml and MBC:8 µg/ml). A synergistic interaction was observed between allicin + nystatin and allicin + CHX (FICI ≤ 0.5). Allicin exhibited significant biofilm eradication against C. albicans and S. aureus biofilms with percentages of 50.0% and 52.6%, respectively. The results of this study suggest a possible application of allicin in treating C. albicans and S. aureus infection in DS.