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In a singular period, such as during a pandemic, the use of personal protective masks can become mandatory for all citizens in many places worldwide. The most used device is the disposable mask that, inevitably, generates a substantial waste flow to send to incineration or landfill. The article examines the most diffused type of disposable face mask and identifies the characteristic of the constituent materials through morphological, chemical, physical, and thermal analyses. Based on these investigations, a mechanical recycling protocol with different approaches is proposed. Advantages and disadvantages of the different recycling solutions are discussed with considerations on necessary separation processes and other treatments. The four solutions investigated lead to a recycling index from 78 to 91% of the starting disposable mask weight. The rheological, mechanical, and thermo-mechanical properties of the final materials obtained from the different recycling approaches are compared with each other and with solutions present on the market resulting in materials potentially industrially exploitable.

The most important research area in robotics is navigation algorithms. Robot path planning (RPP) is the process of choosing the best route for a mobile robot to take before it moves. Finding an ideal or nearly ideal path is referred to as “path planning optimization.” Finding the best solution values that satisfy a single or a number of objectives, such as the shortest, smoothest, and safest path, is the goal. The objective of this study is to present an overview of navigation strategies for mobile robots that utilize three classical approaches, namely: the roadmap approach (RM), cell decomposition (CD), and artificial potential fields (APF), in addition to eleven heuristic approaches, including the genetic algorithm (GA), ant colony optimization (ACO), artificial bee colony (ABC), gray wolf optimization (GWO), shuffled frog-leaping algorithm (SFLA), whale optimization algorithm (WOA), bacterial foraging optimization (BFO), firefly (FF) algorithm, cuckoo search (CS), and bat algorithm (BA), which may be used in various environmental situations. Multiple issues, including dynamic goals, static and dynamic environments, multiple robots, real-time simulation, kinematic analysis, and hybrid algorithms, are addressed in a different set of articles presented in this study. A discussion, as well as thorough tables and charts, will be presented at the end of this work to help readers understand what types of strategies for path planning are developed for use in a wide range of ecological contexts. Therefore, this work’s main contribution is that it provides a broad view of robot path planning, which will make it easier for scientists to study the topic in the near future.

Research-practice partnerships (RPPs) provide opportunities for researchers to support school districts in addressing the complex challenges they face. Cynthia E. Coburn, William R. Penuel, and Caitlin C. Farrell situate RPPs in the history of educational research and discuss the needs they were designed to address. They then describe what contemporary RPPs are and what they do and close by discussing ways that RPPs can contribute to educational improvement and transformation.

When the COVID-19 pandemic began and school buildings had to close, Jennifer Altavilla feared that the research-practice partnership (RPP) she was managing would have to end. However, after a pause in the spring, the partnership resumed in the fall and has continued to thrive. Altavilla reflects on her experience and how it dovetails with the experiences described in the April 2021 Kappan articles on RPPs.

Asian soybean rust (ASR), caused by Phakopsora pachyrhizi, is one of the most serious soybean (Glycine max) diseases in tropical and subtropical regions. To facilitate the development of resistant varieties using gene pyramiding, DNA markers closely linked to seven resistance genes, namely, Rpp1, Rpp1-b, Rpp2, Rpp3, Rpp4, Rpp5, and Rpp6, were identified. Linkage analysis of resistance-related traits and marker genotypes using 13 segregating populations of ASR resistance, including eight previously published by our group and five newly developed populations, identified the resistance loci with markers at intervals of less than 2.0 cM for all seven resistance genes. Inoculation was conducted of the same population with two P. pachyrhizi isolates of different virulence, and two resistant varieties, ‘Kinoshita’ and ‘Shiranui,’ previously thought to only harbor Rpp5, was found to also harbor Rpp3. Markers closely linked to the resistance loci identified in this study will be used for ASR-resistance breeding and the identification of the genes responsible for resistance.

Asian soybean rust (ASR) causes large reductions in soybean yield, affecting the entire grain market. With low fungicide efficiency, the use of resistant cultivars can be an economical, safe, efficient, and sustainable control alternative. However, the great variability and aggressiveness of ASR and the use of Rpp genes are limited. Thus, gene pyramiding is a promising strategy for the development of cultivars with high resistance to a greater number of isolates. Thus, the objective of this study was to evaluate sister lines, previously evaluated by Meira et al. (2022). https://doi.org/10.1007/s10681-020-02667-x), presenting different Rpp-pyramided genes for resistance to Phakopsora pachyrhizi to clarify the pyramiding effect of two originally developed Rpp-pyramided lines compared to two existing lines or lines possessing only a single Rpp of resistance under field conditions. Rpp-pyramided lines 52117-1 (Rpp2 + Rpp1-b), 52117-57 (Rpp2 + Rpp1-b), 52117-59 (Rpp2 + Rpp1-b) + 52117-60 (Rpp2 + Rpp4) showed high resistance levels compared to resistant sources and resistance control, carrying a single Rpp gene PI 200487 (Rpp5), PI 200492 (Rpp1), PI 230970 (Rpp2), PI 459025A (R pp4), and PI 506764 (Rpp3 + Rpp5) with significant reductions in sporulation levels (SL), number of uredinia per lesion (NoU), and frequency of lesions with uredinia (%LU). Only, the line 52117-54 (Rpp2 + Rpp1-b), and 52117-63 (Rpp2 + Rpp4) showed resistance level smaller than PI 594723 (Rpp1-b) and similar resistance levels than PI 230970 (Rpp2), respectively. Rpp-pyramided lines carrying Rpp2 + Rpp1-b (52116-54, 52116-74, 52117-21, 52117-59 and 52117-60), and Rpp2 + Rpp4 (52117-60), and single gene Rpp1-b were classified as “highly resistant” and “resistant”. Furthermore, one sister line, 52117-57 (Rpp2 + Rpp1-b), showed immunity under field conditions. The Rpp-pyramided genes are an alternative for achieving high resistance levels against ASR.

As an asphalt modifier, waste polypropylene (RPP) can not only optimize the performance of asphalt but also greatly alleviate the problem of waste plastic treatment, effectively reducing environmental pollution and resource waste. In order to evaluate the influence of RPP and styrene butadiene styrene (SBS) on asphalt performance, the application of RPP in modified asphalt pavement has been expanded. In this study, a dynamic shear rheometer (DSR), bending beam rheometer (BBR) and other instruments were used to evaluate the rheological properties of composite-modified asphalt. Fourier infrared spectroscopy (FTIR) and fluorescence microscopy (FM) was employed to conduct a microscopic analysis of the modified asphalt, and the layer analysis method was adopted to determine the optimal RPP content. The test results show that the rheological properties of asphalt are significantly improved by the composite modification of RPP and SBS. In addition, the cross-linking between polymer and asphalt is further enhanced by the composite addition of RPP and SBS. The comprehensive performance of modified asphalt is optimized at the RPP content of 2%, which is suitable for applications in the cold temperate zone. The RPP/SBS composite-modified asphalt is able to improve the utilization rate of RPP and has good environmental and economic benefits, thus exhibiting excellent comprehensive performance. However, the optimal asphalt content in the mixture was not investigated, and the economic benefits brought by the utilization of RPP were not evaluated and require further study.

Prompted by the sudden shift to remote instruction in March 2020 brought on by the COVID-19 pandemic, teachers explored online resources to support their students learning from home. We report on how twelve teachers identified and creatively leveraged open educational resources (OERs) and practices to facilitate self-directed science learning. Based on interviews and logged data, we illustrate how teachers’ use of OER starkly differed from the typical uses of technology for transmitting information or increasing productivity. These experiences provide insights into ways teachers and professional developers can take advantage of OER to promote self-directed learning when in-person instruction resumes.

Asian soybean rust (ASR), caused by the fungus Phakopsora pachyrhizi , is the main disease affecting soybean in Brazil. This study aimed at investigating and mapping the resistance of the PI 594756 to P. pachyrhizi , by using Bulked Segregant Analysis (BSA). The PI 594756 and the susceptible PI 594891 were crossed and the resulting F 2 and F 2:3 populations (208 and 1770 plants, respectively) were tested against ASR. Also, these PIs and differential varieties were tested against a panel of monosporic isolates. Plants presenting tan lesions were classified as susceptible ( S ) while plants presenting reddish-brown (RB) lesions were classified as resistant. DNA bulks were genotyped with Infinium BeadChips and the genomic region identified was further analyzed in the F 2 individuals with target GBS (tGBS). PI 594,56 presented a unique resistance profile compared to the differential varieties. The resistance was monogenic dominant; however, it was classified as incompletely dominant when quantitatively studied. Genetic and QTL mapping placed the PI 594756 gene between the genomic region located at 55,863,741 and 56,123,516 bp of chromosome 18. This position is slightly upstream mapping positions of Rpp1 (PI 200492) and Rpp1-b (PI 594538A). Finally, we performed a haplotype analysis in a whole genomic sequencing-SNP database composed of Brazilian historical germplasm and sources of Rpp genes. We found SNPs that successfully differentiated the new PI 594756 allele from Rpp1 and Rpp1-b sources. The haplotype identified can be used as a tool for marker-assisted selection (MAS).

Research-practice partnerships (RPPs) are long-term collaborations between researchers and practitioners aimed at educational improvement and transformation through engagement with research. Yet RPPs can be challenging to implement, and even long running RPPs experience bumps in their work together. Caitlin Farrell, Laura Wentworth, and Michelle Nayfack discuss what conditions helped school district leaders and researchers from the partnership between Stanford University and San Francisco Unified School District be more or less successful in influencing school district policies and practices, and they share recommendations on how to develop or support conditions for successful partnerships.