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Soils with a significant proportion of clay or silt tend to have poor geotechnical characteristics (such as volumetric change and low strength) when exposed to varying moisture contents. The chemical stabilizers currently used are costly and have negative effects on the environment. Arkansas, in the United States, is the leading producer of rice in the country. During rice production, ~20% of the harvested grain consists of rice husk (RH). The rice milling process produces ash with a considerable amount of silicate. Research is being conducted to address the environmental concerns associated with its disposal in Arkansas, as there is growing interest in using rice husk ash (RHA) as a stabilizing additive for problematic soils. For RHA to be effective, an activator such as lime may be needed. The present study focuses on investigating the effectiveness of RHA in stabilizing substandard soils, as no prior study has used RHA as a stabilizing agent in the United States. Additionally, the research aims to determine the optimal proportions of RHA, hydrated lime (HL), or a combination of both. The study employs varying percentages of RHA (3%, 6%, and 9%) and HL (1%, 3%, and 5%) in a unary system. In the binary system, 3%, 4%, and 5% of RHA are combined with 1% HL. The study includes a range of routine tests, such as assessments of Atterberg limits, modified proctor compaction, pH levels, California bearing ratio (CBR), unconfined compressive strength (UCS), and free swell (FS). Furthermore, results from scanning electron microscopy (SEM) coupled with X‐ray diffractometer analyses demonstrated significant improvements in UCS and CBR values for the treated soils, indicating enhanced strength and stability. Moreover, the FS test reveals a reduction in swelling characteristics for the stabilized soils. It was found the optimal dosages of RHA and HL were 6% and 3%, respectively. Notably, when RHA and HL were combined, a blend of these two stabilizing agents exhibited the most promising results in terms of improving the swelling. The optimum percentage of the combined stabilizing agents was 4% RHA + 1% HL. The findings of this proof‐of‐concept research hold substantial potential for the construction industry in Arkansas, offering cost‐effective alternatives to conventional soil stabilization methods while promoting the sustainable and environmentally conscious use of RHA. [ABSTRACT FROM AUTHOR]

The Arkansas Department of Transportation (ARDOT) Maintenance Division is concerned about the use of certain aggregates in asphalt mixture because of their durability and performance issues. Good performance of the pavements can be ensured by selecting good-quality aggregates along with asphalt binders that can produce compatible aggregate–binder systems. The primary goal of this research was to determine proper asphalt binders and aggregates for the construction of highways in Arkansas. Three performance grade (PG) asphalt binders, namely PG 64-22, PG 70-22, and PG 76-22, prepared from two different crude sources, were investigated. This study also included four types of ARDOT-commissioned aggregates, namely gravel, sandstone, limestone, and dolomite, from four quarries throughout Arkansas. Selected properties of asphalt binders and aggregates (e.g., physical, mechanical, and chemical) were evaluated by performing a series of routine laboratory tests. To evaluate the performance of the asphalt mixtures, work of cohesion, work of adhesion, and boiling resistance tests were conducted. These aggregates, binders, and aggregate–binder systems were ranked based on the properties obtained from laboratory tests. In general, any combination of dolomite or limestone with a stiffer binder such as PG 76-22 or PG 70-22 is expected to be superior to an asphalt mixture with either sandstone or gravel. The outcomes of this research will help highway agencies and pavement professionals in selecting suitable asphalt binders and aggregates for long-lasting pavement construction. [ABSTRACT FROM AUTHOR]

The Next Generation Science Standards (NGSS) and other national frameworks are calling for much more sophisticated approaches to STEM education, centered around the integration of complex experimentation (including real labs, not just simulations), data collection and analysis, modeling, and data-driven argumentation, i.e., students can behave like real scientists. How to implement such complex approaches in scalable ways is an unsolved challenge - both for presential and distance education. Here we report on the iterative design and large-scale deployment of an open online course with a "biology cloud experimentation lab" (using living cells) that engaged remote learners (> 300 students) in the scientific practices of experimentation, modeling and data analysis to investigate the phototaxis of a microorganism. We demonstrate (1) the robustness and scalability of the cloud lab technology (> 2,300 experiments run), (2) the design principles and synergistic integration of multiple UI and learning activities and suitable data formats to facilitate NGSS-aligned science activities, and (3) design features that leverages the natural variability of real biology experiments to instigate authentic inquiry. This platform and course content are now suited for large-scale adaptation in formal K-16 education; and we provide recommendations for inquiry-based science learning in general.

Introduction: Children with cerebral palsy (CP) in Bangladesh suffer immensely, with no means or hope for a decent life and a public system lacking basic facilities. This study aims to analyze the quality of life (QoL) and depression status of parents among children with CP, as well as the relationship between these factors and their demographic profile. Materials and Methods: This is a descriptive cross-sectional study in which data were collected from the Pediatric Department of Centre for the Rehabilitation of the Paralysed (CRP) in Savar. The participants included 150 children with CP between January 2018 and December 2020. Results: The mean age of the mothers (29.86±6.14) was between 25 and 29 years (32.7%). The most common type of CP was spastic CP among 100 mothers (66.7%). A significant relationship was observed between the mother's age during marriage and World Health Organization quality of life (WHOQoL-BREF), physical health (P<0.01), psychological health (P<0.01), and the age group of 31-35 years had the lowest scores (Mean±SD 62.00±5.16, 51±0.683) in both domains. A strong correlation (P<0.001) was observed between QoL, physical health (r=0.319), psychological (r=0.365), social (r=0.390) and environmental (r=0.388). From the box plot, QoL showed that spastic CP posed good QoL for mild depression while all other types had neither poor nor good QoL. Conclusion: A hidden issue in every parent is that CP children are the misfortune of their fate that increases their level of depression and consequently decreases their QoL. [ABSTRACT FROM AUTHOR]

Background Burns cause the most severe injuries and are a major public health concern worldwide. It is common in third-world countries and it greatly increases mortality and illness there. Because of the long period of time spent in the hospital and the effort required to recover from a burn, it is one of the most costly injuries to treat. Objectives The aim of this study was to identify the priming factors related to burn injury among people in Bangladesh. Materials and Methods The study design was cross-sectional. Total 121 samples were selected conveniently for the study and the study was conducted in several hospital settings in Chittagong, Savar and Dhaka city like Chittagong Medical College Hospital, Enam Medical College Hospital, and Sheikh Hasina Burn Hospital. Data was collected by using a self-administered questionnaire. Statistical Analysis Descriptive and inferential statistics (chi-squared test) were used for data analysis that focused through tables. Results On average, people were 22.43 (14.399) years old. Of the total of 121 patients, 48.1% were female (n = 58) and 52.1% were male (n = 63). Among the participants, 56.2% (n = 68) were hurt accidentally, 33.9% (n = 41) were injured on the job, 2.5% (n = 3) were harmed intentionally, and 7.4% (n = 9) were injured while preparing food. In case of occurrence, 37.2% (n = 45) were burned by fire, 38.8% (n = 47) were electrical burn and 23.9% (n = 29) were chemical or scald type burn. Conclusions Most burn injuries are accidental, such as cooking fires, hot water, electric lines, and acid throwing that are significantly considered as the priming factors of burn injury among people in Bangladesh. The lack of awareness and ignorance causes these accidents and insufficient training causes most the electrical burns. [ABSTRACT FROM AUTHOR]

Compatibility holds great importance because it can predict the overall performance of asphalt mixtures. Incompatible aggregate-binder duos can result in a weak and friable mix as well as increase mixtures' stripping potential. Being unaware, local agencies and contractors often struggle with premature pavement failure, which consequently places unexpected strain on the budget. Thus, this study assessed the compatibility among 18 asphalt binders with a performance grade (PG) of PG 64-22, PG 70-22, and PG 76-22, each collected from six different refineries; and eight different types of aggregates (sandstone, novaculite, limestone, and dolomite, each collected from two different quarries). Viscosity, penetration, pH, and work of cohesion values of binders were used to develop a binder ranking system. Similarly, the aggregates were ranked based on physical (specific gravity and absorption), durability (abrasion resistance and soundness), and chemical (pH and surface free energy) properties. Overall relative rankings of aggregates and binders were also provided by assigning weight factors to different tested parameters. A total of 144 aggregate-binder mixture systems were ranked based on their dry and wet work of adhesion values as well as Texas boiling test results. The compatibility ratio (CR) was also computed, and each of the systems was designated A, B, C, or D based on their relative CR values. Upon analysis, three binders (S2B2, S3B1, and S4B1) and three aggregates (DM2, LS2, and DM1) were designated as the most preferable construction materials. CR values predicted LS2, DM1, and DM2 mixtures as the most compatible mixtures. SS2, LS1, and DM2 mixtures showed the highest stripping resistance in the Texas boiling test. These databases are expected to help the agency and asphalt producers to select compatible binders and aggregates for producing durable asphalt concrete. This study covered a wide variety of aggregates and asphalt binders prevalent in but not limited to Arkansas. A database developed under this project was based on observed individual aggregates' and binders' performances as well as their combined performances. The information provided in this study will help contractors and agencies to choose the most appropriate aggregate-binder system within their reach for producing quality asphalt mixtures. By knowing the rankings, state agencies can adjust project budgets and assign timely rehabilitation due to the usage of less compatible aggregate-binder systems. Contractors can tweak the existing mix design if they must use local but inferior materials. This ranking will also help them to select project-specific materials depending on the project's significance. The refineries as well will have the opportunity to improve their products to be more compatible with local materials. [ABSTRACT FROM AUTHOR]