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In the 2023 phase of the international collaborative DECOVALEX modeling project, Task E focused on understanding thermal, hydrological, and mechanical (THM) processes related to predicting brine migration in the excavation damaged zone around a heated excavation in salt. Salt is attractive as a disposal medium for radioactive waste because it is self-healing and is essentially impermeable and non-porous in the far field. Investigation of the short-term, near-field behavior is important for radioactive waste disposal because this early period strongly controls the amount of inflowing brine. Brine leads to corrosion of waste forms and waste packages, and possible dissolution of radionuclides with brine transport being a potential transport vector to the accessible environment.The Task was divided into steps. Step 0 included matching unheated brine inflow data from boreholes at the Waste Isolation Pilot Plant (WIPP) and matching temperature observations during a Brine Availability Test in Salt (BATS) heater test. Step 1 included validation of models against a thermo-poroelastic analytical solution, and two-phase flow around an excavation. Finally, Step 2 required all the individual components covered in steps 0 and 1 to come together to match observed brine inflow behavior during the same BATS heater test.There were a range of approaches from the teams, from mechanistic to prescriptive. Given the uncertainties in the problem, some teams used one- or two-dimensional models of the processes, while other teams included more geometrical complexity in three-dimensional models. Task E was a learning experience for the teams involved, and feedback from the modeling teams has led to changes in follow-on BATS experiments at WIPP. The primary Task E lessons learned were the impact of hydrologic initialization methods (wetting up vs. drying down), the difference between confined and unconfined thermal expansion, and the large changes in permeability associated with heating and cooling.

This research paper focuses on the thermo-hydro-mechanical (THM) modeling of brine migration in a heated borehole test conducted as part of the ongoing Brine Availability Test in Salt (BATS) at the Waste Isolation Pilot Plant (WIPP) in New Mexico. It is a component of the international collaboration project DECOVALEX-2023 (DEvelopment of COupled models and their VALidation against EXperiments), which aims to understand the THM processes governing brine flow in heated rock salt repositories through collaborative analysis by multiple research teams. Using the TOUGH–FLAC simulator, THM simulations were performed and compared with data from the BATS phase 1a. This experiment involved two identical horizontal-borehole arrays, one heated and one serving as a control, both equipped with sensor arrays. Analysis of measurements revealed water flow rate surges during heater power transitions, with the highest jump observed during cooling. Acoustic emission activity exhibited distinct patterns in response to heater power changes, suggesting that damage to rock salt is particularly pronounced during the cooling phase. The THM simulations successfully captured these phenomena, highlighting the significance of thermal effects, brine migration, and mechanical behavior in predicting brine availability in heated and damaged rock salt. Our modeling also revealed the critical interplay between heating and cooling-induced damage and its influence on flow properties, particularly affecting brine inflow estimation. Notably, we found that cooling-induced brine inflow spikes result from increased permeability due to tensile dilatancy. These findings have important implications for the development of robust containment strategies and enhance our understanding of the complex processes involved in repository performance.

Abstract Objective To assess the current status of digital technology (DT) implementation in prosthodontics post-graduate (PG) programs in Saudi Arabian dental institutions. Methodology A 19-item survey was created using Google forms and the link was emailed to the 29 prosthodontics PG program directors (advanced clinical training and joint program) in Saudi Arabia. The questionnaire contained five Sect. 1) didactic training and DT usage in PG preclinical, clinical and laboratory training, 2) incorporation of DT in PG program, 3) utilization of DT and the types of cases treated by PG students during their course, 4) information on the faculties involved in prosthodontics PG education, and 5) potential challenges encountered and program directors’ satisfaction of the PG program. Descriptive statistics was used to present the frequencies and proportions, and Chi square inferential test was used to compare the participants’ response based on the type of PG programs (α = 0.05). Results Only 28 program directors responded to the survey, yielding a 95.5% response rate. Among the program directors, 24 (85.7%) and 4 (14.3%) directors supervised the advanced clinical training and joint programs, respectively. Among the DT, CAD/CAM was the most used technology (50–80%), followed by intra-oral scanning (28–96%). Digital technology implementation was largely limited by lack of resources or equipment (67%), cost (53%) and scarcity of PG teaching staff (46%). A significant difference was observed between the programs regarding the mandatory use of DT for their cases (p = 0.03). Conclusions This multi-institutional survey of program directors revealed that DT is continuously implemented in the last few years. Saudi dental institutions must prioritize implementing and utilizing DT in PG training to graduate competent prosthodontists in this fast-paced digital era. While DT is pivotal in dental education, its implementation is limited in many institutions due to resources or equipment, cost, and lack of trained faculty.

Due to the widespread distribution of emerging pollutants (EPs) and their potential impact on ecosystems and public health, evaluating and creating wastewater treatment techniques to reduce EPs is a global priority. Tackling the removal of EPs from the environment has become a significant challenge for researchers, spurred by the growing awareness of their prevalence and associated risks. Among the existing techniques, adsorption utilizing diverse adsorbents emerges as the most cost-effective and widely applicable approach. Understanding adsorption isotherms is crucial for the assessment and optimization of adsorbent materials used in the adsorption approach used to remove EPs from wastewater. The investigation of adsorption isotherms offers a versatile and effective approach to pollutant removal in addition to helping to optimize treatment protocols. Numerous adsorbents and adsorption isotherms have been explored for the removal of EPs from wastewater. This review focuses on developing new adsorbents with a strong emphasis on their long-term environmental impact. To improve pharmaceutical removal efficiency, exploring innovative bio-adsorption methods is key. Prioritizing sustainable design and scalability considerations is essential for advancing polysaccharide-based adsorbents. A multidisciplinary approach is crucial for assessing practical applicability, considering potential obstacles. Enhancing the scalability and real-world efficacy of adsorption techniques in wastewater treatment relies on strategic resource allocation and field research. This study examines new materials, stresses standardized procedures, and offers recommendations for improving adsorption-based wastewater treatment for EPs.

The objective of this study was to investigate how the gender and school level factors relate to disruptive behaviors during physical education (PE) classes in Tunisian schools. The study sample consisted of 632 Tunisian students aged 12-19 years, with 43.2% of them being boys and 56.8% girls. Among the participants, 64.9% were middle school students, while 33.1% were secondary school students. Self-reported data was collected using the 20-item "Physical Education Classroom Instrument." Data was analyzed for a potential "Disruptive behavior × Gender" association, as well as a "Disruptive behavior × School level" association using the Pearson Chi-square (X[superscript 2]) test. The key findings signaled that boys were more likely than girls to behave aggressively, distract/disturb others, and demonstrate poor self-management during PE classes. On the other hand, secondary school students are less likely than middle school students to behave aggressively and irresponsibly, disobey directions, distract others, and demonstrate poor self-management. These findings suggest associations between gender and school level with disruptive behaviors among Tunisian students during PE classes. By recognizing these associations, educators and policymakers can develop targeted interventions and strategies to effectively manage and mitigate disruptive behaviors in Tunisian PE settings.

This study investigated whether the use of the color wheel system (CWS) during physical education (PE) classes is associated with a significant decrease in disruptive behaviors among middle school students. Using a multiple-baseline single-case design, we investigated the effects of the CWS on disruptive behavior in nine middle school students with identified disruptive tendencies, aged 13.33 ± 1.1 years on average. Disruptive behaviors were tracked through observation using a 15-s partial time sampling technique. The results, as indicated by time series graphs and Nonoverlap of All Pairs values ranging from 0.79 to 1.00, consistently demonstrated that the implementation of the CWS led to a reduction in disruptive behaviors across the three classrooms. The findings suggest that the CWS is an effective intervention for mitigating disruptive behaviors among school-aged children during PE classes. However, it should be noted that the training procedures for implementing the CWS were relatively brief. To address potential limitations in future CWS implementations, it is recommended to address these shortcomings and carefully consider the implementation of the CWS as a behavioral intervention in PE.

Salt formations are a promising host rock for the disposal of heat-emitting nuclear waste due to their ability to heal fractures, high thermal conductivity, and near-zero permeability. This study investigates the concept of waste emplacement in salt formations by placing waste packages in drifts and backfilling them with crushed salt. The aim is to minimize fracturing and restore the initial properties of the host rock. One of the key issues in assessing the safety and performance of nuclear waste repositories in salt is determining the reconsolidation rate of the crushed salt backfill, which has been traditionally predicted using the C-WIPP model. However, this model was calibrated using data from uniaxial oedometer lab tests, where specimens with high initial porosity values have been compacted to medium porosity values. The observed compaction behavior has then been extrapolated to the low porosity range, leading to a prediction of rapid full reconsolidation of the backfill in less than 20 years. In contrast, the new C-WIPP/TUC model used in this study was calibrated for the medium porosity range, between 17% and 8%, based on more suitable triaxial lab tests. Using coupled Thermo-Hydro-Mechanical (THM) simulations with the TOUGH-FLAC simulator, it was found that the C-WIPP/TUC model predicts a slower reconsolidation rate of the backfill compared to the C-WIPP model, with an average porosity of the backfill remaining roughly 10 times that of natural salt after 10,000 years. The effects of the relatively slow reconsolidation of the crushed salt backfill on the THM behavior of the repository are also examined, highlighting the importance of accurately capturing the behavior of crushed salt for the study of the long-term integrity of a nuclear waste repository in salt.