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Pyrotechnology is a key element of hominin evolution. The identification of fire in early hominin sites relies primarily on an initial visual assessment of artifacts' physical alterations, resulting in potential underestimation of the prevalence of fire in the archaeological record. Here, we used a suite of spectroscopic techniques to counter the absence of visual signatures for fire and demonstrate the presence of burnt fauna and lithics at the Lower Paleolithic (LP) open-air site of Evron Quarry (Israel), dated between 1.0 and 0.8 Mya and roughly contemporaneous to Gesher Benot Ya'aqov where early pyrotechnology has been documented. We propose reexamining finds from other LP sites lacking visual clues of pyrotechnology to yield a renewed perspective on the origin, evolution, and spatiotemporal dispersal of the relationship between early hominin behavior and fire use.

This article focuses the assessment of the recreational potential of selected water-filled quarries in Slovakia, specifically the Škrabské, Beňatina, and Kraľovany quarries. Water-filled quarries represent a significant untapped resource that can contribute to the development of various leisure activities while simultaneously supporting local communities and environmental conservation. The main challenge of the study is finding a balance between the recreational use of these sites and the need to maintain ecological sustainability, which requires a detailed evaluation of the natural conditions, infrastructure, and accessibility of the individual quarries. The study focuses on a comprehensive assessment of the recreational potential of selected water-filled quarries in Slovakia, specifically the Škrabské, Beňatina, and Kraľovany quarries, using a methodology based on point evaluation according to criteria such as natural beauty, accessibility, existing infrastructure, and ecological status. The results of this study provide an important foundation for further research and decision-making processes in the transformation of water-filled quarries, aiming to maximize their recreational potential while ensuring long-term environmental sustainability.

Concrete mechanical properties could be improved through adding different materials at the mixing stage. Quarry dust (QD) is the waste produced by manufactured sand machines and comprise approximately 30–40% of the total quantity of QD generated. When it dries, it transforms into a fine dust that poses a tremendous hazard to the environment by contaminating the soil and water and seriously endangering human health. QD utilization in concrete is one of the best options. Though a lot of scholars focus on imitation of QD in concrete, knowledge is scattered, and a detailed review is required. This review collects the information regarding QD-based concrete, including fresh properties, strength, durability, and microstructure analysis. The results indicate that QD is suitable for concrete to a certain extent, but higher percentages adversely affect properties of concrete due to absence of fluidity. The review also indicates that up to 40–50% substitution of QD as a fine aggregate can be utilized in concrete with no harmful effects on strength and durability. Furthermore, although QD possesses cementitious properties and can be used as cement substitute to some extent, less research has explored this area.

The article examines the increase in the slope angle of the working side of the quarry depending on the width of the strip of additional reserves to be opened after the end of the sliding rear sight separation above the roof of the ore body and the annual rate of deepening along the contact of the ore body from the horizontal displacement velocity of the rear sight. The graphs are constructed for the case of use on board a single rear sight, the deposit is located in a zone of disagreement in the area of peak volumes of \"overhanging\" overburden. The charting shows that the nature of the change in the rate of advance of the mining front in both types of phased mining is the same (parabolic dependence), and the intensity of mining operations in cascade mining is higher. The two studied mining procedures are compared (against the background of the traditional non-staged one) according to the calendar distribution of ore volumes and overburden.

The article considers the systems of opening the contiguous reserves of upland deposits and develops their classification. Proposed classification takes into account the development of both portside and sub-quarry reserves in an open-underground way using the quarry space. Opening workings of sub-quarry reserves are carried out outside the boundaries of the quarry.

Quarry waste is a fine rock aggregate produced as a by‐product of the rock‐crushing process in quarries which is environmentally hazardous when poorly disposed. This paper presents the results of a study carried out to explore the feasibility of recycling basaltic quarry waste (BQW) with waste high‐density polyethylene (HDPE) into sustainable construction materials. Recycled HDPE/BQW formulations were melt‐mixed in a single‐screw extruder and then transfer‐moulded into experimental samples. No significant chemical transformations were detected by Fourier transform infrared spectroscopy. Thermogravimetric analyses showed an improvement in the thermal stability of HDPE with the addition of BQW. Scanning electron microscopy imaging revealed generally poor adhesion between the two phases. Both tensile and impact strength initially increased but decreased at higher filler loading. However, stiffness, compressive strength, compressive modulus, density, and hardness improved with filler content for all particle sizes. The increase in water absorption with increasing filler content was not significant. This study demonstrates that BQW is a suitable filler for HDPE and the resulting material may be used to make roofing tiles and paving blocks.

Dewatering involves reducing level of flooding of field by various technical measure. This paper studies the methods of dewatering involving reducing the level of flooding of field by various technical measure water from surface quarries with the help of horizontal drilling. Horizontal drilling does not cause discomfort at the level of exploitation works, transport and storage of deposits being a very efficient method. This has a great advantage both in terms of efficiency and the level of the environment because it eliminates land cover.

Background Musculoskeletal disorders (MSDs) are common work-related conditions that affect the musculoskeletal system owing to poor ergonomic practices, overexertion, and repetitive motions. Globally, MSDs account for a significant proportion of disabilities due to the physical tasks and demanding nature of jobs. Despite global efforts to reduce occupational hazards, little information is available on MSDs among quarry workers in Gambia. Therefore, this study aimed to explore the prevalence of MSDs and their associated factors in quarry workers in Gambia. Methods This study adopted an analytical cross-sectional design that was conducted in 2023. A total of 258 quarry workers were selected from 4 quarries in the West Coast Region. Participants were randomly selected and the Standardised Nordic Questionnaire (SNQ) was modified and used with additional structured questionnaires. Data were collected using the Kobo Collect App and analyzed using IBM SPSS version 27.0. Bivariate analysis was conducted using binary logistic regression, Pearson’s chi-square test, point-biserial correlation, and Fisher’s exact test to identify the association between predictors and outcome variables. Statistical significance was considered at a p -value < 0.05, and the significance was also reported using an adjusted odds ratio (aOR) with a 95% Confidence Interval (CI). Results The study revealed a high MSD prevalence of 93% among quarry workers, with the most affected body parts being the lower back (90.3%), shoulders (68.1%), and upper back (61.3%). Significant associations were observed between MSDs and factors such as nationality ( p  = 0.048), job description ( p  = 0.047), BMI score ( p  < 0.001), periodic health examination ( p  = 0.031), years of experience ( p  = 0.029), health and safety training ( p  = 0.044), and lifting or carrying weights ( p  = 0.044). Quarry workers whose nationality was Gambian had 82.8% (aOR = 0.172; 95% CI = 0.048–0.619) reduced odds of sustaining MSDs when compared to respondents whose nationality was non-Gambian. Increasing years of experience had 15.0% (aOR = 0.850; 95% CI = 0.725–0.997), increase in hours of daily work had 40.3% (aOR = 0.597; 95% CI = 0.386–0.925), and increasing BMI score had 29.9% (aOR = 0.701; 95% CI = 0.584–0.841) reduction in the odds of sustaining MSDs. However, increasing household size among quarry workers had 1.26 (aOR = 1.261; 95% CI = 1.015–1.566) higher odds of sustaining MSDs. Conclusion This study underscores a critical public health concern with the high prevalence of MSDs among quarry workers in The Gambia, which is associated with poor ergonomic training and inadequate safety training. Reducing the burden of MSDs in this population requires interventions that focus on better working conditions, ergonomic training, and regular health evaluations.

Rock slope failures pose significant challenges in geotechnical engineering due to the intricate nature of rock masses, discontinuities, and various destabilizing factors during and after excavation. In mining industries, such as national cement factories, multi-benched excavation systems are commonly used for quarrying. However, cut slopes are often designed with steep angles to maximize economic benefits, inadvertently neglecting critical slope stability issues. This oversight can lead to slope instability, endangering human lives and property. This study focuses on analyzing the stability of existing quarry cut slopes, estimating their final depth, and conducting a parametric study of geometric profiles including bench height, width, face angle, and rump width. Kinematic analysis helps identify potential failure modes. The results reveal that the existing quarry cut slope is prone to toppling, wedge failure, and planar failure with probabilities of 42.68%, 19.53%, and 14.23%, respectively. Numerical modeling using the finite element method (Phase2 8.0 software) was performed under both static and dynamic loading conditions. The shear reduction factor (SRF) of the existing quarry cut slope was 1.01 under static loading and 0.86 under dynamic loading. Similarly, for the estimated depth, the SRF was 0.82 under static loading and 0.7 under dynamic loading. These values indicate that the slope stability falls significantly below the minimum acceptable SRF, rendering it unstable. The parametric study highlights the face angle of the bench as the most influential parameter in slope stability. By adjusting the bench face angle from 90° to 75°, 70°, and 65°, the SRF increased by 31.6%, 35.4%, and 37.9%, respectively. Among these, a 70° bench face angle is recommended for optimal stability with a SRF of 1.27 under static loading and 1.18 under dynamic loading.