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Many real-world problems of statistical inference involve dependent bivariate data including survival analysis. This paper presents new nonparametric methods for predictive inference for survival analysis involving a future bivariate observation. The method combine between bivariate Nonparametric Predictive Inference (NPI) for the marginals with parametric copula to take dependence structure into account. The proposed method is a discretized version of the parametric copula. The NPI fits the marginal and very straight forward computations. Generally, NPI is a frequentist approach which infer a future observation based on past data. The proposed method resulting imprecision is robustness with regard to the assumed parametric copula in the marginal for prediction. This is practical for small data set. The suggestion is to use a basic parametric copula for small data sets. We investigate and discuss the performance of these methods by presenting results from simulation studies. The method is further illustrated via application in survival analysis using data sets from the literature.

Bacterial growth in food sources after harvesting and during food manufacturing has emerged as a major agricultural concern. Currently, several chemical preservatives have been added to foods to prevent or inhibit bacterial growth. These phenomena, however, become a concern when consumers begin to demand the safety of the food they consume, thus resulting in a search for natural plant extracts as an alternative. The antimicrobial activity of Cosmos caudatus leaf extract against six food pathogens was thus investigated in the present work. The disc-diffusion test, the minimum inhibitory concentration (MIC), and the minimum bactericidal concentration (MBC) tests were used to determine the antibacterial potential. Time-kill kinetics were used to determine their killing endpoints at various incubation times. Thereafter, Bacillus cereus was selected as a representative bacterium to be viewed under the light sheet electron microscope (LSEM) to observe the morphological changes. For the application as a sanitiser, different concentrations of C. caudatus extract were applied to chicken meat and oyster mushroom to determine bacterial reduction and sensory acceptability. The toxicity test using brine shrimp lethality assay was also performed to determine the toxicity level of C. caudatus extract. Results showed that C. caudatus extract contain five major peaks of flavonoids. In the antibacterial test, all tested pathogens were inhibited, with B. cereus being the most susceptible, with a significant reduction time of more than 3 log10 at 3.125 mg/mL. Under LSEM, the population of B. cereus was reduced, and the shape was wrinkled. In the application, C. caudatus extract at 0.05% for 5 min treatment time was chosen as the best formulation, whereas the brine shrimp tests showed that C. caudatus extract was safe for human consumption (LC50: 3.54 mg/mL). In conclusion, C. caudatus extract could have the potential to be further explored as a natural food sanitiser. [ABSTRACT FROM AUTHOR]

The youth age group is a phase of life associated with risk-taking behaviour and challenging moral issues. This study aimed to provide electrophysiological evidence that could explain the interaction between attentional bias towards the health-risk of smoking and non-health risk behaviour stimuli as influenced by various levels of moral identity. Seventy eight eligible subjects (mean age of 22 ± 2.1 years old) participated in the event-related potential session. Attentional bias towards the visual stimuli was determined by recording the N200 brain potential while participants emotionally reacted to the target (health-risk of smoking, nonhealth risk behaviour) and non-target (neutral) stimuli. N200 was extracted and analysed by using a mixed-design analysis of variance with target and non-target stimuli as within subject effects and types of moral identity as between subject effects. Attentional bias towards visual stimuli interacted significantly with the different levels of moral identity in the central part of the brain. High internalisation trait indicated shorter N200 latency when reacted to the health-risk of smoking stimuli than the non-health risk behaviour stimuli. An important insight regarding to moral psychology in relation to youth health risk behaviour was highlighted to focus for the development of the health promotion and education in future. [ABSTRACT FROM AUTHOR]

The railway track’s sub-ballast layer is important, but it is often neglected, leading to the contamination and blockage of voids, as well as track deformation and degradation. These issues occur when fouling materials infiltrate the subballast due to load-induced vibration. The purposes of this paper are to investigate the influence of vibration on the sub-ballast layer when loads are applied to a fouled ballast and to determine whether sub-ballast saturation should be ignored. A ballast box was fabricated to represent actual railway conditions and filled with 100 kg of ballast aggregates containing fouling materials (crushed ballast, sand, clay, and coal) proportional to the ballast weight. In addition, a vibratory compactor plate machine was used to simulate load on the fouled ballast, inducing vibrations that caused fouling materials to migrate into the sub-ballast. The results indicate that 18% of crushed ballast, 20% of sand, 20.7% of clay, and 15% of coal infiltrated the sub-ballast due to loading-induced vibration, and fouling infiltration percentages rose as vibration from loading increased. These percentages exceeded the standard 10% weight of fouling infiltration into the sub-ballast, indicating an unfavourable subballast condition and showing that sub-ballast saturation should not be ignored. These findings have significant implications for maintenance engineers, as they underscore the need for continuous monitoring and upkeep to ensure optimal sub-ballast performance. [ABSTRACT FROM AUTHOR]

The evaluation of fundamental mechanical properties of bitumen is vital to construct long-term performing pavements. This research evaluates cohesive bond strength of bitumen and mastics using compression pull-off test (CPOT). The results show problems in the common interpretation of load-displacement curves. A discussion is made on fibrillary nucleation in binder. The curing for 24 h is sufficient for the development of the cohesive bond. Furthermore, longer conditioning is needed to evaluate the moisture damage using aluminium plates. Bitumen source, grade, filler content, and loading rate affect the pull-off strength (POS). Ageing increases POS and shifts the failure mode towards brittle. The type of filler does not affect POS after short-term ageing. The moisture conditioning reduces the POS and results in a mixed to adhesive failure with increased variability in results. The aggregate plates are necessary for detailed moisture damage evaluation. The use of re-used aggregate substrate is found to be ineffective. [ABSTRACT FROM AUTHOR]

Abstract Workers are driven to work faster in the industrial work environment to meet high productivity targets. An increased work pace leads to increased muscle activation. However, the effect of work pace on bilateral upper trapezius muscles during sewing machine operation in an industrial work environment has not been thoroughly investigated in experimental studies. Therefore, this research aims to conduct an experimental study to analyze the bilateral upper trapezius muscle activity of industrial sewing machine operators at different levels of work pace. Thirty subjects (15 males, and 15 females) continuously performed the sewing operation for two hours in an industrial work environment. Experiments were conducted for two levels of work pace i.e. low pace (100% of standard cycle time) and high pace (120% of standard cycle time). Electromyographic signals were recorded from the bilateral upper trapezius muscles. The EMG amplitude (RMS) among the muscles was computed. A statistically significant (p