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Step counting devices were previously shown to be efficient in a variety of applications such as athletic training or patient's care programs. Various sensor placements and algorithms were previously experimented, with a best mean absolute percentage error (MAPE) close to 1% in simple mono-activity walking conditions. In this study, an existing running shoe was first instrumented with an inertial measurement unit (IMU) and used in the context of multi-activity trials, at various speeds, and including several transition phases. A total of 21 participants with diverse profiles (gender, age, BMI, activity style) completed the trial. The data recorded was used to develop a step counting algorithm based on a deep learning approach, and further validated against a k-fold cross validation process. The results revealed that the step counts were highly correlated to gyroscopes and accelerometers norms, and secondarily to vertical acceleration. Reducing input data to only those three vectors showed a very small decrease in the prediction performance. After the fine-tuning of the algorithm, a MAPE of 0.75% was obtained. Our results show that such very high performances can be expected even in multi-activity conditions and with low computational resource needs making this approach suitable for embedded devices. [ABSTRACT FROM AUTHOR]

Slipping due to insufficient friction with flooring can cause fatal injuries in workplaces and homes. Oak wood flooring is commonly used in construction to build these environments. In the manufacturing process, wood finishing is conducted at the end of the process to strengthen the properties and longevity of the wood, although it could impact the coefficient of friction (COF) causing slip falls. Vegetable oils, such as macadamia nut and walnut oils, used as wood finishes have gained prominence due to their beneficial aspects to the environment. However, little is known about their effectiveness as a safe coating for wood floors. It was hypothesized that if oak wood was coated with macadamia nut oil, it would be the most effective at increasing the COF as it is the most viscous of the finishes. Both vegetable oil finishes were compared to a control group with no finish, as well as a common polyurethane finish. After being coated, the COF of the wood materials was measured by sliding a rubber shoe sole along the wood, attached to a Vernier Force Sensor. A one-way ANOVA with an alpha value of 0.05 suggested the results were significant (p < .001). The post-hoc Tukey test found significant differences in all experimental groups, with polyurethane finish having the highest mean COF of 0.77, while macadamia nut had a COF of 0.40. Both vegetable oils were considered unsafe by OSHA guidelines of a COF of 0.5, emphasizing the effectiveness of chemical finishes such as polyurethane. [ABSTRACT FROM AUTHOR]

This research developed shoe soles using a biodegradable and renewable composite made of King Oyster mushroom mycelium. An exploratory approach was used to develop biodegradable shoe prototypes using the mushroom mycelium composite as the midsoles. An online survey was conducted to evaluate the consumer acceptance of the shoe prototypes and a wear test with undergraduate college students was conducted to evaluate the consumer acceptance, wearability, and comfort of the shoe prototype. The survey results indicated that consumers liked the new sustainable footwear and were likely to purchase it. Indian consumers liked the new shoes more and would be more willing to purchase the new shoes than the U.S. consumers. The young age group would be more willing to buy this sustainable shoe prototype than the old age group. The consumers who were frequent consumers of sustainable products, willing to pay more for an environmentally friendly product, and cared about the environment were more likely to purchase this sustainable shoe prototype. The wear test with a small sample of four college students had split opinions on the comfort and wearability of the shoes. Still, all of them liked the concept of shoe materials and biodegradable shoes made from renewable materials. [ABSTRACT FROM AUTHOR]

The Migazzi palace in Cogolo (Val di Pejo, Trentino, Italy), an important alpine noble residence of medieval origin, was analysed through dendrochronology. The floor and ceiling beams, cladding boards, door lintels, loose timber, and anything that could be dendrochronologically dated were examined. For each room, at least one sample containing the "waney edge" (the last ring before the bark) was found, allowing for precise dating of the different building phases. The results completely changed our knowledge of the palace's history. Initially thought to date back to the 15th century, the tower around which the successive structures were built was dated to the first half of the 14th century (1332). In the space between the floor and the ceiling below, materials used as filler were found, including wooden elements and parts of footwear. The sole of one shoe was dated to 1501, which frames the cultural context of Lombard influence in which the palace flourished. This work has accurately reconstructed the history of the building, demonstrating the potential offered by intensive and widespread dendrochronological sampling. [ABSTRACT FROM AUTHOR]

This essay examines two shoe soles cut from a Torah scroll which British historian and collector of Judaica Cecil Roth collected in Greece in 1946. As Holocaust relics, the Torah scroll shoe soles are, in turn, sacred and sacrilegious, texts and objects, Greek Jewish and non-Jewish Greek artifacts. Roth's recovery of the shoe soles is compromised by occurring under the auspices of the British Army during the Greek Civil War and in the controversial climate of collecting Judaica displaced by the Holocaust. I discuss the ongoing story of the shoe soles: their separation, their use, and their best location. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Textiles & Engineers / Tekstil ve Mühendis is the property of Union of Chambers of Turkish Engineers & Architects, Chamber of Textile Engineers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The goal of this study was to use the finite element (FE) method to compare and study the differences between bionic shoes (BS) and normal shoes (NS) forefoot strike patterns when running. In addition, we separated the forefoot area when forefoot running as a way to create a small and independent area of instability. An adult male of Chinese descent was recruited for this investigation (age: 26 years old; body height: 185 cm; body mass: 82 kg) (forefoot strike patterns). We analyzed forefoot running under two different conditions through FE analysis, and used bone stress distribution feature classification and recognition for further analysis. The metatarsal stress values in forefoot strike patterns with BS were less than with NS. Additionally, the bone stress classification of features and the recognition accuracy rate of metatarsal (MT) 2, MT3 and MT5 were higher than other foot bones in the first 5%, 10%, 20% and 50% of nodes. BS forefoot running helped reduce the probability of occurrence of metatarsal stress fractures. In addition, the findings further revealed that BS may have important implications for the prevention of hallux valgus, which may be more effective in adolescent children. Finally, this study presents a post-processing method for FE results, which is of great significance for further understanding and exploration of FE results. [ABSTRACT FROM AUTHOR]

Using a curved carbon-fiber plate (CFP) in running shoes may offer notable performance benefit over flat plates, yet there is a lack of research exploring the influence of CFP geometry on internal foot loading during running. The objective of this study was to investigate the effects of CFP mechanical characteristics on forefoot biomechanics in terms of plantar pressure, bone stress distribution, and contact force transmission during a simulated impact peak moment in forefoot strike running. We employed a finite element model of the foot-shoe system, wherein various CFP configurations, including three stiffnesses (stiff, stiffer, and stiffest) and two shapes (flat plate (FCFP) and curved plate (CCFP)), were integrated into the shoe sole. Comparing the shoes with no CFP (NCFP) to those with CFP, we consistently observed a reduction in peak forefoot plantar pressure with increasing CFP stiffness. This decrease in pressure was even more notable in a CCFP demonstrating a further reduction in peak pressure ranging from 5.51 to 12.62%, compared to FCFP models. Both FCFP and CCFP designs had a negligible impact on reducing the maximum stress experienced by the 2nd and 3rd metatarsals. However, they greatly influenced the stress distribution in other metatarsal bones. These CFP designs seem to optimize the load transfer pathway, enabling a more uniform force transmission by mainly reducing contact force on the medial columns (the first three rays, measuring 0.333 times body weight for FCFP and 0.335 for CCFP in stiffest condition, compared to 0.373 in NCFP). We concluded that employing a curved CFP in running shoes could be more beneficial from an injury prevention perspective by inducing less peak pressure under the metatarsal heads while not worsening their stress state compared to flat plates. [ABSTRACT FROM AUTHOR]

A position identification system for wandering elderly people uses BLE to transmit ID information. The objective of this study is to make the BLE module batteryless using a piezoelectric element. The piezoelectric element is mounted on the sole of a shoe, and when pressure is applied to the piezoelectric element by walking, a voltage is generated between both electrodes of the piezoelectric element. This voltage is used to store the necessary power as a battery to operate the BLE module. In this paper, we provide a step-by-step design approach using piezoelectric elements attached to a shoe to power an actual BLE module. We derive an equivalent circuit for the piezoelectric element under walking conditions and, through circuit simulation and actual measurements, clarify the amount of time required to charge the voltage to drive the BLE, demonstrating the possibility of a batteryless BLE module for use in locating a wanderer while they are walking. [ABSTRACT FROM AUTHOR]

To prevent frostbite in cold environments, proper dimensions and materials for different parts of shoes along with the optimal design of shoe geometry were investigated. Furthermore, the optimal geometry of shoes was computed using an optimization algorithm to provide maximum thermal protection for the foot while having the lowest weight. The results showed that the length of the shoe sole and the thickness of the sock are the most effective parameters in foot protection against frostbite. Using thicker socks, which only increased the weight by roughly 11%, enhanced the minimum foot temperature by more than 2.3 times. Optimal design of shoe geometry is used to prevent frostbite in cold environments. A model of a biothermal nonlinear model is developed for the barefoot. Length of the shoe sole and the thickness of the sock are the most effective parameters in protecting the foot against frostbite. For the selected weather conditions, the toes are most likely to have frostbite. The best shoe for the selected weather conditions is the shoe that has the highest amount of thermal insulation in the toe area. [ABSTRACT FROM AUTHOR]

Copyright of Industria Textila is the property of Institutul National de Cercetare-Dezvoltare pentru Textile si Pielarie and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: It is generally accepted that shoes and floors are contaminated with pathogens including methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci (VRE), and Clostridium difficile, yet correlation to clinical infection is not well established. Because floors and shoes are low-touch surfaces, these are considered non-critical surfaces for cleaning and disinfection. The purpose of this review is to assess peer-reviewed literature inclusive of floors and shoe soles as contributors to the dissemination of infectious pathogens within healthcare settings. Methods: Using the Preferred Reporting Items for Systematic Reviews (PRISMA) methodology, PubMed and Medline were searched for articles assessing the presence of pathogens on or the transmission of pathogens between or from floors or shoe soles/shoe covers. Inclusion criteria are the human population within healthcare or controlled experimental settings after 1999 and available in English. Results: Four hundred eighteen articles were screened, and 18 articles documented recovery of bacterial and viral pathogens from both floors and shoes. Seventy-two percent (13/18) of these were published after 2015, showing increased consideration of the transfer of pathogens to high-touch surfaces from shoe soles or floors during patient care. Conclusions: There is evidence that floors and shoes in healthcare settings are contaminated with several different species of health-care–associated pathogens including MRSA, VRE, and Clostridium difficile. [ABSTRACT FROM AUTHOR]

The study aimed to define the load on hands using various commonly used types of crutches while walking with a full load on both legs (FL), with 20 kg partial load (PL), or with the left leg wholly unloaded (UL). Twenty‐six healthy subjects used crutches with ergonomic handles, with anatomic handles (wider and softer bearing surface), and arthritis crutches (horizontal supporting area for the forearm). Sensor mats between hand and handles continuously measured the load transmitted, while sensor soles in the shoes recorded the ground reaction forces simultaneously. The load on the palm and separately the radial and ulnar halves of the palm were analyzed. With arthritis crutches, significantly lower load was transferred to the hands compared to forearm crutches (FL 3% vs. 25% of body weight, PL 8% vs. 87%, UL 12% vs. 103%). The load on hands increased significantly from FL to PL and UL for both types of crutches. The ipsilateral left hand had to bear significantly more load than the right hand. However, the feet's time‐ground reaction curves showed more irregularities, and PL on the left leg was significantly higher with arthritis crutches. Anatomic handles reduced the load on the ulnar half of the palm (FL 3% vs. 5%, PL 13% vs. 18%, UL 17% vs. 23%); the radial half of the palm had a similar load to bear with both types of handles (11/11%, 31/32%, 34/35%). Arthritis crutches allow unburdening hands at the expense of gait stability. Anatomic handles reduce the load on the Guyon's canal. [ABSTRACT FROM AUTHOR]

In forensic practice, evaluating shoeprint evidence is challenging because the differences between images of two different outsoles can be subtle. In this paper, we propose a deep transfer learning‐based matching algorithm called the Shoe‐MS algorithm that quantifies the similarity between two outsole images. The Shoe‐MS algorithm consists of a Siamese neural network for two input images followed by a transfer learning component to extract features from outsole impression images. The added layers are finely tuned using images of shoe soles. To test the performance of the method we propose, we use a study dataset that is both realistic and challenging. The pairs of images for which we know ground truth include (1) close non‐matches and (2) mock‐crime scene pairs. The Shoe‐MS algorithm performed well in terms of prediction accuracy and was able to determine the source of pairs of outsole images, even when comparisons were challenging. When using a score‐based likelihood ratio, the algorithm made the correct decision with high probability in a test of the hypothesis that images had a common source. An important advantage of the proposed approach is that pairs of images can be compared without alignment. In initial tests, Shoe‐MS exhibited better‐discriminating power than existing methods. [ABSTRACT FROM AUTHOR]

We developed a shoe sole sensor system with four high-capacity, compact triaxial force sensors using a nitrogen added chromium strain-sensitive thin film mounted on the sole of a shoe. Walking experiments were performed, including straight walking and turning (side-step and cross-step turning), in six healthy young male participants and two healthy young female participants wearing the sole sensor system. A regression model to predict three-directional ground reaction forces (GRFs) from force sensor outputs was created using multiple linear regression and Gaussian process regression (GPR). The predicted GRF values were compared with the GRF values measured with a force plate. In the model trained on data from the straight walking and turning trials, the percent root-mean-square error (%RMSE) for predicting the GRFs in the anteroposterior and vertical directions was less than 15%, except for the GRF in the mediolateral direction. The model trained separately for straight walking, side-step turning, and cross-step turning showed a %RMSE of less than 15% in all directions in the GPR model, which is considered accurate for practical use. [ABSTRACT FROM AUTHOR]

Nowadays, biocomposites represent a new generation of materials that are environmentally friendly, cost-effective, low-density, and not derived from petroleum. They have been widely used to protect the environment and generate new alternatives in the polymer industry. In this study, we incorporated untreated jute fibers (UJFs) and alkaline-treated jute fibers (TJFs) at 1–5 and 10 phr into TSR 10 natural rubber as reinforcement fillers. These composites were produced to be used in countersole shoes manufacturing. Untreated fibers were compared to those treated with 10% sodium hydroxide. The alkali treatment allowed the incorporation of fibers without compromising their mechanical properties. The TJF samples exhibited 8% less hardness, 70% more tensile strength, and the same flexibility compared to their pure rubber counterparts. Thanks to their properties and ergonomic appearance, the composites obtained here can be useful in many applications: construction materials (sound insulating boards, and flooring materials), the automotive industry (interior moldings), the footwear industry (shoe soles), and anti-static moldings. These new compounds can be employed in innovative processes to reduce their carbon footprint and negative impact on our planet. Using the Lorenz–Park equation, the loaded composites examined in this study exhibited values above 0.7, which means a competitive load–rubber interaction. Scanning electron microscopy (SEM) was used to investigate the morphology of the composites in detail. [ABSTRACT FROM AUTHOR]

Industrial waste disposal is one of the major environmental concerns faced by all nations today. The present work describes the thermal degradation kinetics of polyurethane rich shoe sole waste (PUW) filled natural rubber (NR) composites and their transport behavior in various solvents. NR composites with PUW were prepared by incorporating it in the range 0–10 phr (parts per hundred rubber). The thermal behavior of the NR-PUW composites was researched by thermogravimetric analysis (TGA) at 30–600 °C. Kinetics of thermal degradation was studied by plotting thermogravimetric curve at four distinct heating rates, viz., 7.5, 10, 15, 20 °C min−1. The energy of activation (Ea) calculated using Flynn–Wall–Oszaka (FWO), Kissinger–Akahira–Sunose (KAS), Tang and Starink models were found to be well correlated. The NR composite with 7.5 phr PUW showed higher Ea proving its better thermal stability compared to other composites. Multi-step degradation kinetics of the composites was evidenced by the variation in energy of activation as conversion increases. The solvent transport behavior of the composites was investigated in toluene, xylene, hexane, and petrol. Swelling was found to be maximum for toluene and solvent uptake decreases with further PUW loading. The diffusion parameters of the composites exhibited a decreasing trend as PUW increases. [ABSTRACT FROM AUTHOR]

In recent years, human activity monitoring and recognition have gained importance in providing valuable information to improve the quality of life. A lack of activity can cause health problems including falling, depression, and decreased mobility. Continuous activity monitoring can be useful to prevent progressive health problems. With this purpose, this study presents a wireless smart insole with four force-sensitive resistors (FSRs) that monitor foot contact states during activities for both indoor and outdoor use. The designed insole is a compact solution and provides walking comfort with a slim and flexible structure. Moreover, the inertial measurement unit (IMU) sensors designed in our previous study were used to collect 3-axis accelerometer and 3-axis gyroscope outputs. Smart insoles were located in the shoe sole for both right and left feet, and two IMU sensors were attached to the thigh area of each leg. The sensor outputs were collected and recorded from forty healthy volunteers for eight different gait-based activities including walking uphill and descending stairs. The obtained datasets were separated into three categories; foot contact states, the combination of acceleration and gyroscope outputs, and a set of all sensor outputs. The dataset for each category was separately fed into deep learning algorithms, namely, convolutional long–short-term memory neural networks. The performance of each neural network for each category type was examined. The results show that the neural network using only foot contact states presents 90.1% accuracy and provides better performance than the combination of acceleration and gyroscope datasets for activity recognition. Moreover, the neural network presents the best results with 93.4% accuracy using a combination of all the data compared with the other two categories. [ABSTRACT FROM AUTHOR]

Aiming at the problem of poor shoe shape applicability in the automatic sole gluing system, a cross-source point cloud registration algorithm based on modified PCA (principal components analysis) and bidirectional ICP (iterative closest point) was proposed. Comparing the influence of the three sampling methods on the final registration accuracy, the farthest point down-sampling was selected as the preprocessing of the point cloud before registration; a modified PCA was proposed to perform coarse registration on the sole point cloud, providing a better initial transformation matrix for accurate registration; the bidirectional ICP with good robustness of cross-source point cloud registration was used for precise registration; according to the accurate registration results, the standard gluing trajectory was migrated to the real-time sole gluing system, so as to obtain the real-time gluing trajectory. The results show that the modified PCA + bidirectional ICP is superior in fast and accurate registration of cross-source shoe sole point clouds, and the error of bidirectional ICP is reduced to 1.31 mm after 20 iterations, which is 1.13 mm less than that of the traditional ICP algorithm; The modified PCA + bidirectional ICP algorithm has better applicability and accuracy when dealing with different shoe types, and the registration time also meets the system requirements. This algorithm can improve the applicability of the traditional sole gluing system to various types of shoes, and has certain engineering practical value. [ABSTRACT FROM AUTHOR]

The footwear industry is moving towards automation and intellectualization. To overcome the drawbacks of the high-cost and low-efficiency traditional manual shoe sole gluing process, automatic methods were utilized for generating spray trajectories. Currently, most of the reported automatic methods for generating spray trajectories mainly rely on the outer contour bias method. However, the glue is only applied to the area near the edge/contour of shoe soles and the fixed offset distance in the outer contour bias method cannot adapt to the immense amount of shoe styles with high precision and achieve applicability for irregular and unique sole designs. An intuitive yet logical approach to fulfill the requirements is to utilize the deconvolutional neural network for generating shoe sole spray trajectories. In this work, we treated the glue trajectory prediction as an image-to-image prediction and established a novel deconvolutional neural network to generate shoe sole spray trajectories. The as-proposed deconvolutional neural network for generating spray trajectory offered significant advantages over the existing bias-based methods, including: (1) based on the novel deconvolutional neural network, the proposed method for generating shoe sole spray trajectories exhibits greater applicability to irregular shoe soles, which improves the spray accuracy without compromising the spray efficiency; (2) we discard all the pooling layers, which only consist of convolutional and deconvolutional layers, to preserve more spatial information and achieve higher spray accuracy through end-to-end mapping from shoe sole images to shoe sole spray trajectories, resulting in an improved spray accuracy without sacrificing spray efficiency. The Dice similarity coefficient and Hausdorff distance were used as the evaluation metrics to assess the performance of our approach. Our proposed method showed an ultra-high accuracy and precision with a Dice similarity coefficient over 99.25% and a Hausdorff distance less than 1.2 mm, which are ~10% higher than the spray accuracy of other reported traditional methods. Our findings would bring significant improvements to the field of automatic shoe sole spray trajectory generation, which has the potential to promote the utilization of intelligent technologies in the footwear industry. [ABSTRACT FROM AUTHOR]

This work deals with the development and characterization of biodegradable polymer composites based on of polyvinyl chloride (PVC) and wood waste (WW) postconsumer waste. Wood waste resulting from wood processing into finished products is cryogenically ground to min. 500 nm, mechanically functionalized at temperature with polydimethylsiloxane (PDMS) (7%) and compounded in varying proportions (10%, 20%, 50%). The new composite is biodegradable due to the compounding with wood fibers, have low density and implicitly the products made from, a lower weight, reduced costs and recover waste. Soles for shoes will be processed by injection using these materials. [ABSTRACT FROM AUTHOR]

Although sources of faecal pathogens abound in urban environments, faecal bacteria on city streets remain largely unquantified. The extent to which faecal pathogens transfer between outdoor and indoor environments is also poorly understood. We use defined substrate analysis to quantify enterococci and coliform faecal indicator bacteria (FIB) on interior floor surfaces in a New York City institutional building, on shoe soles of building occupants and on exterior sidewalks. Enterococci and faecal coliforms are ubiquitous on interior floors, varying with foot traffic and floor surface type. Mean enterococci counts are highest in the heavily trafficked building entryway compared with less trafficked interior locations, and counts are significantly higher on carpets than on adjacent uncarpeted flooring. Enterococci and faecal coliforms appear on shoe soles of building occupants as well. Susceptibility of shoe sole bacteria to antimicrobial agents is commensurate with that of cultivated E. coli, E. faecalis and S. aureus strains. In pooled rainwater on city sidewalks, enterococci average 31,000 per 100 mL. Overall, our evidence indicates ubiquity of FIB on sidewalks, a translocation pathway via shoe soles and accumulation on indoor floor surfaces, particularly carpeted areas. These findings present ample opportunity for human exposure to faecal pathogens in the indoor environment. [ABSTRACT FROM AUTHOR]

Copyright of China Rubber Industry is the property of Editorial Office of China Rubber Industry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The effect of natural rubber (NR) on the mechanical and performance properties of ground tire rubber (GTR) has been investigated. The mechanical properties of vulcanized GTR/NR blends were determined in a universal testing machine. It was found a decreasing in the mechanical properties of the GTR/NR blends as the number of re-vulcanization processes increases. This behavior was attributed to the decrease in the concentration on GTR in the vulcanized GTR/NR blend with respect to the next one, and to a structural net degradation into the re-vulcanized GTR/NR blend due to the reversion process (over vulcanization). In the loss modulus charts was observed that the peaks of the curves got smaller and wide as the re-vulcanization process increased, due to the mechanical loses and elastic gains of the GTR/NR re-vulcanized blends. On the other hand, in the performance results was found that the cut growth values of Flexion Ross were more affected by the thickness of the plaque of vulcanized rubber than for the number of re-vulcanization processes of the GTR/NR blend. In addition, as the re-vulcanization processes increased, the structural degradation of the tridimensional cross-linked net, increased as well, more severely from the fourth re-vulcanization process. It could be concluded that the GTR/NR blends with high GTR content, could be used in the sole shoe fabrication, taking care that the thickness is ≤ 4.5 mm, and that the GTR/NR blends have not been subjected to more than two re-vulcanization processes. [ABSTRACT FROM AUTHOR]

• Macroscopic assessment via image analysis aimed to explore environmental trace evidence dynamics. • Transfer and persistence of soils to footwear and diatomaceous earth to clothing was tested. • Both environmental traces were retained and visually identifiable during one week of wear. • Soil type, clothing type, & body positioning significantly impacted persistence and distribution. • Recognising the presence of trace evidence is a critical first step in the forensic process. Environmental trace evidence offers useful circumstantial intelligence to link persons and scenes of forensic interest. An increasing empirical research base is dedicated towards understanding the transfer and persistence dynamics of environmental indicators including pollen, soils, and diatoms, within a diverse range of experimental frameworks. This paper presents two discrete studies exploring transfer and persistence of soils and sediments on footwear and diatomaceous earth adhered to clothing in forensically pertinent scenarios. Variables including sediment type, foot position, clothing type, and body positioning were also explored throughout. Both experiments incorporated a field-based methodology during the sampling effort. Photographs were collected of an initial transfer sample and of a retained assemblage following hours, days, and up to one-week of wear, facilitating macroscopic assessment of trace evidence dynamics. All images were processed using accessible, open-source software before spatial analysis of evidence distribution within and temporal assessment (% retention) upon each evidential surface. The results highlighted consistent loss of transferred sediment from footwear with significantly greater retention of loamy clay soil than dune sand which was absent beyond 24 h of wear. Loss was not influenced by wearer gait but was more rapid from those areas of the shoe sole in direct contact with the ground. Diatomaceous earth was retrieved from all three clothing types tested after one week – significant losses of material occurred before 48 h with a consistent assemblage identified beyond this. Denim was significantly more effective than acrylic and fleece for diatomaceous earth retention and significantly more material was lost from clothing worn on the lower body. These findings highlight the value of using visual environmental markers and a macroscopic analytical approach during the investigation of environmental trace dynamics. The methodology offers a novel, non-destructive assessment of soil and diatom transfer and persistence, complementing more extensive laboratory-based examinations to ensure the development of a well-rounded research base within the forensic sciences. [ABSTRACT FROM AUTHOR]

Copyright of Ingeniería (0121-750X) is the property of Ingenieria and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The refrigeration industry produces millions of tons of waste polyurethane (PU) every year, which can cause environmental damage and human health problems. This article analyzes the use of waste PU as filler in composites made of styrene butadiene rubber (SBR) and natural rubber (NR) to produce shoe soles. The interfacial interaction of said filler was evaluated by the Flory–Rehner method (swelling) using the equation developed by Lorenz–Park. The results of this evaluation were later compared with those obtained by the Mooney–Rivlin method using the data from stress–strain tests. According to the results of the tensile strength tests, the composites filled with waste PU present stress–strain curves that are like those of metallic materials that have low elastic strength but high plastic strength. Using the Lorenz–Park equation, the filled composites examined in this study exhibited values above 0.7, which means a strong filler–rubber interaction. Scanning Electron Microscopy and Fourier‐Transform Infrared Spectroscopy were used to investigate the morphology of the composites in detail. [ABSTRACT FROM AUTHOR]