Electronics Testing Center

Shear bond strength is a critical indicator of the bonding efficiency between pavement layers, playing a pivotal role in applications such as the stress-absorbing membrane interlayer (SAMI), which are designed to improve crack resistance and extend the life span of road pavements. This study explores the influence of two additives, low-density polyethylene (LDPE) and cement kiln dust (CKD), on the shear strength and stiffness of SAMI blends. Various proportions of LDPE (2%, 4%, and 6%) and CKD (4%, 8%, and 12%) were incorporated into SAMI formulations, and their effects were assessed using a specialized shear bond strength test. The findings revealed a progressive increase in peak shear strength, maximum shear strain, and stiffness with higher additive concentrations. SAMI blends containing LDPE exhibited the highest shear strain, along with superior ductility and flexibility when compared with the control blend, where the maximum shear strain occurred in the blend with 6% LDPE, reaching 0.042, compared with 0.037 for the control blend. Notably, the blends containing both LDPE and CKD demonstrated the best performance, achieving the highest peak shear strength of 0.58 MPa and stiffness of 0.2 MPa/mm, outperforming the control blend (0.34 MPa and 0.096 MPa/mm). Furthermore, these blends showed enhanced energy-absorption capacity, as indicated by the area under the shear strength-displacement curve before and after reaching peak shear strength. The blend containing 4% LDPE and 8% CKD achieved a total area of 9.29 MPa.mm under the curve, compared with the 6.3 MPa.mm of the control blend. In conclusion, the incorporation of LDPE and CKD into SAMI blends resulted in significant improvements in mechanical properties, offering a possible lower risk of reflective cracking and the potential for longer pavement life.

BackgroundChronic constipation, common in clinical practice, requires treatment to enhance quality of life and possibly extend life expectancy. However, predictors of treatment efficacy remain largely unexplored. This study aimed to identify factors predicting treatment success in patients with chronic constipation.MethodsA multicenter, prospective observational study evaluated patients with moderate to severe chronic constipation using the Chronic Constipation-Therapeutic Efficacy and Satisfaction Test (CC-TEST) questionnaire. Symptoms were assessed before treatment and at 2 and 4 weeks post-treatment. Multivariate analyses identified predictive factors based on three treatment efficacy assessment criteria: patient’s impression, numeric rating scale (NRS) for symptom intensity, and spontaneous bowel movement (SBM) frequency status.ResultsConstipation medications were administered to 97 patients, with significant symptom improvements observed at 2 and 4 weeks (CC-TEST). The greatest effects were seen in hard stools, difficulty in defecation, and infrequent bowel movements. In the multiple regression analysis, baseline clinical characteristics and symptom profiles were not significant predictors of treatment response. Incorporating 2-week treatment responsiveness revealed that non-responsiveness at 2 weeks (β = 0.487), and a lower stool symptom subscale score (β = -0.344), were associated with poorer patient’s impression. For the NRS, non-responsiveness at 2 weeks (β = 0.279) was a significant predictor. For SBM, non-responsiveness at 2 weeks (β = -0.274) predicted outcomes. Including 2-week non-responsiveness improved the predictive accuracy for 4-week efficacy.ConclusionsThe therapeutic response at 2 weeks is the most significant predictor of subsequent treatment response at 4 weeks in patients with chronic constipation.

Soil quality plays a key role in sustainable agricultural productivity, particularly in semi-arid regions where fertility constraints limit crop performance. Microbial biofertilizers represent environmentally friendly alternatives to chemical fertilizers by enhancing nutrient availability and soil health. This study evaluated the effects of Bacillus subtilis and Aspergillus niger inoculations on the physicochemical properties of agricultural soils from the Béni Mellal region of Morocco. A total of 84 soil samples were analyzed, divided into four groups: untreated control, inoculated with B. subtilis, inoculated with A. niger, and combined inoculated. The results showed distinct treatment-dependent responses. B. subtilis significantly enhanced total nitrogen (N), while A. niger increased available phosphorus (P 2 O 5 ) and influenced soil pH. Combined inoculation produced the most pronounced improvements, particularly for total nitrogen, available phosphorus, ammonium, and boron. Manganese (Mn) exhibited moderate but consistent variation among treatments, while organic matter (OM), carbon dioxide (CO 2 ), iron (Fe), copper (Cu), and zinc (Zn) showed no significant short-term changes. Correlation analysis indicated strong positive associations among key nutrients, suggesting synergistic effects of microbial inoculation. Overall, the findings highlight the potential of Bacillus subtilis and Aspergillus niger, especially when combined, to selectively improve soil fertility and support more sustainable agricultural practices in the Beni Mellal region.

This paper deals with the investigation of the acoustic emission (AE) testing applicability for the evaluation of components manufactured via selective laser sintering (SLS) and direct laser deposition (DLD) technologies. The experimental procedure involved the examination of a pressure vessel and a welded spatial structure using the A-Line PCI-1 AE system. Amplitude-energy characteristics of AE signals were recorded during two loading cycles, and sources‘ localization was then performed. The correlation was established between AE activity and the presence of plastic deformation zones as well as stress concentration regions, particularly within weld areas and at material transition interfaces. The results were validated through strain gauge measurements and plastic strain assessments. These findings highlight the necessity to revise the existing AE source classification criteria to further reflect the specific characteristics of additive manufactured structures. As a result, it leads to improved reliability of structural integrity evaluation.

The purpose of this study was to examine the effect of using authentic materials in improving English language skills of grade 1 students of SD Muhammadiyah 1 Bandar Lampung. Pre-experimental design with quantitative approach was used in this study. The research sample was 28 students taken using cluster sampling technique. Through pre-test and post-test, data was collected and then analyzed using Wilcoxon test to determine the effect of using Authentic Materials in English learning, with significance results between pre-test and post-test (p < 0.05), with an average pre-test score of 12.9 and post-test score of 70.0. The results of this study indicate that the use of authentic materials can be an effective teaching medium in improving the English language skills of grade 1 students.

Background and Aim:Research confirming the ability of cariogenic bacteria Streptococcus mutans to degrade dental resin composites and adhesives is of great concern as it points a finger on the clinical longevity of the restoration. Incorporation of antibacterial particles to the composite may serve as a potent solution to overcome this detrimental effect. This study evaluated the antimicrobial efficacy, antibiofilm effect, and resistance to biodegradation of a novel composite and commercial composite incorporated with zinc oxide nanoparticles (ZnO-NPs) against S. mutans.Materials and Methodology:Thirty six samples (12 samples each) of Group I (Tetric N Ceram), Group II (Novel composite, Sri Chitra Tirunal Institute for Medical Sciences and Technology [SCTIMST]), and Group III (Tetric N Ceram incorporated with 5 wt% ZnO-NPs) were prepared for the study. Antibacterial efficacy was measured using direct contact test, antibiofilm effect was tested on 7-day-old biofilm using live-dead staining and viewed under confocal Raman microscope, and resistance to biodegradation was measured using high performance liquid chromatography, all tested against S. mutans.Results:Intergroup evaluation of antimicrobial efficacy, antibiofilm effect, and resistance to biodegradation showed that Group II and Group III showed significantly favorable results as compared to Group I, tested using analysis of variance followed by post hoc analysis.Conclusion:The novel composite (SCTIMST) and composite incorporated with 5 wt% ZnO-NPs have better antibacterial property, antibiofilm effect, and resistance to biodegradation as compared to the unmodified composite, against S. mutans.

Abstract This study considers the estimation of marginal reliability and conditional accuracy measures using a generalized recursion procedure with several IRT‐based ability and score estimators. The estimators include MLE, TCC, and EAP abilities, and corresponding test scores obtained with different weightings of the item scores. We consider reliability estimates for 1‐, 2‐, and 3‐parameter logistic IRT models (1PL, 2PL, and 3PL) for tests of dichotomously scored items, using IRT calibrations from two datasets. The generalized recursion procedure is shown to produce conditional probability distributions for the considered IRT estimators that can be used in the estimation of marginal reliabilities and conditional accuracies (biases and CSEMs). These reliabilities and conditional accuracies are shown to have less extreme and more plausible values compared to theoretical approaches based on test information. The proposed recursion procedure for the estimation of reliability and other accuracy measures are demonstrated for testing situations involving different test lengths, IRT models, and different types of IRT parameter inaccuracies.

This experiment evaluates the effectiveness of a lab‐developed anti‐motion sickness app for smartphones and tablets. Thirty‐two participants underwent tests with controlled vehicle dynamics and varied conditions. The app employs a U‐shaped reference image and an adaptive video player to reduce discomfort. Data collected using MISC and SSQ demonstrated that the app significantly reduced motion sickness symptoms, especially with smartphones.

With the rapid development of positioning, localization, navigation, and self-driving car systems, the implementation of intelligent and robust localization systems for real-time location-based services (LBSs) has become increasingly attractive. This article presents high-performance positioning and tracking approaches characterized by a pipelined structure, high computational efficiency, flexibility, and real-time processing, implemented using field programmable gate arrays (FPGAs). In triangulation-based positioning approaches, estimated distance information is derived from communication signals and the path loss model, while vertical localization is achieved through the characteristics of barometric pressure (BP). After integrating positioning approaches with tracking methods and BP sensors, the results illustrate that the proposed localization algorithms closely estimate the trajectory of mobile devices. For FPGA-implemented algorithms, the proposed approaches effectively handle floating-point operations, reduce computing resource usage, and provide real-time processing capabilities, surpassing software-based designs and implementations. In terms of performance, the results demonstrate that the localization accuracy of the proposed hardware-based implementation is nearly identical to that of the software-based approach. Regarding vertical location accuracy, based on the proposed calibration approach, the BP value increases by 11.6 Pa for every one-meter decrease in altitude. To maintain floor-level accuracy over time despite atmospheric fluctuations, a real-time dynamic calibration mechanism using a fixed reference sensor is employed. In summary, the proposed localization algorithms, implemented with FPGAs and BP sensors, offer advantages such as lower circuit costs, higher processing efficiency, and reliable vertical location accuracy for real-time public safety LBS.