Search Results (293)

Whole-body vibration (WBV) exposure presents occupational health risks across multiple industries, particularly in tasks involving heavy machinery and prolonged seating. This study examines WBV risk factors, intervention strategies, and the potential for digital monitoring solutions to strengthen workplace safety. A sector-wide analysis assessed vibration exposure levels, worker-reported discomfort, and the effectiveness of the existing control measures. The study introduces a conceptual framework for a mobile application designed to integrate real-time exposure tracking, structured worker feedback, and predictive risk assessment. The findings confirm that WBV exposure varies across industries, with the energy and maritime logistics sectors showing the highest levels of noncompliance. A tiered intervention strategy, classified by impact and effort, provides a structured method for prioritizing risk reduction measures. Immediate actions, such as real-time monitoring and preventive maintenance, require minimal effort but provide high-impact benefits, while long-term strategies, including ergonomic workstation redesign, demand greater investment but contribute to sustained exposure reduction. The proposed framework offers a scalable, data-driven approach to WBV risk management, transitioning workplace safety from compliance-based monitoring to proactive prevention. Future research should explore implementation feasibility, worker adoption, and the integration of AI-driven safety recommendations to support continuous improvements in workplace safety strategies. Full article

Probabilistic random vibration can speed up wear and tear on several components of the tracked vehicle, including the track system, drivetrain, and suspension. Extended exposure to high levels of vibration can cause structural damage to the vehicle frame and other critical components. Assessing random vibration in track vehicles requires a comprehensive approach that considers both the root causes and potential consequences of the vibrations. This random vibration significantly influences the structural performance of suspension arm which is key component of tracked vehicle. Damage due to fatigue is conventionally computed using time domain loaded signals with stress or strain data. This approach generally holds good when loading is periodic in nature but not be a good choice when dynamic resonance is in process. In this case an alternative frequency domain fatigue life analysis is used where the random loads and responses are characterized using a concept called Power spectral density (PSD). The current research article investigates the fatigue damage characteristics of a tracked vehicle suspension arm considering the dynamic loads induced by traversing on smooth and rough terrain. The analysis focusses on assessing the damage and stress response Power spectral density (PSD) ground-based excitation which is termed PSD-G acceleration. Quasi Static Finite Element Method based approach is used to simulate the operational conditions experienced by the suspension arm. Through comprehensive numerical simulations, the fatigue damage accumulation patterns are examined, providing insights into the structure integrity and performance durability of the suspension arm under varying operational scenarios. The obtained stress response PSD data and fatigue damage showed that the rough terrain response exhibits higher stresses in suspension arm. The accumulated stresses in case of rough terrain may prompt to brittle failure at specific critical locations. This research contributes to the advancement to the design and optimization strategies for tracked vehicle components enhancing their reliability and longevity in demanding operational environments. Full article

Aiming at the inherent nature and complexity of the influence of in-orbit micro-vibration in the imaging quality of segmented telescopes, a dynamic full-link opto-mechanical integration analysis method is proposed. The method is based on the measured micro-vibration signals of the infrared refrigerator, using the finite element method to perform the transient response analysis of the opto-mechanical system in Patran/Nastran software. The interface tool is written by Matlab to achieve the calculation of rigid body displacement and real-time data interaction with Zemax. The results show that when the working wavelength is 1 μm, the optical system has a wavefront error Root-Mean-Square value of less than 0.071λ in 4 s. Evaluating the effect of micro-vibration on the imaging quality of the system in terms of the peak ratio of the point spread function. When the exposure time was 2 s, the ratio maximum values of 0.4628 and 0.6207 were reached for the X-axis and Y-axis, respectively. The method provides an important reference basis for the evaluation of imaging quality of an optical system under micro-vibration environment with a long exposure time. Full article

Background/Objectives: Magnetic hyperthermia (MH) has emerged as a promising alternative to conventional cancer treatments, offering targeted tumor destruction with minimal damage to healthy tissues. In this study, we synthesized manganese-doped magnetic nanoflowers (Mn-NFs) using a polyol-mediated approach to enhance heating efficiency and biocompatibility for MH applications. Our objective was to evaluate their structural, magnetic, and in vitro hyperthermic properties to determine their potential for lung cancer therapy. Methods: Mn-NFs, with the general formula MnxFe₃-xO₄ (x = 0, 0.3, 0.5, 0.7), were synthesized via a one-step polyol method and characterized using transmission electron microscopy (TEM), X-ray diffraction (XRD), and vibrating sample magnetometry (VSM). Their heating efficiency was assessed through specific absorption rate (SAR) measurements in aqueous and solid environments under an alternating magnetic field (AMF). Cytocompatibility was evaluated using the Alamar Blue assay on A549 lung carcinoma cells. Cellular uptake was quantified via a colorimetric iron determination method, while in vitro MH efficacy was tested by subjecting Mn-NF-loaded A549 cells to AMF exposure at different field strengths and nanoparticle concentrations. Results: Mn-NFs exhibited a flower-like morphology with enhanced magnetic properties, achieving high SAR values, particularly in immobilized conditions. Cytotoxicity assays confirmed high biocompatibility at relevant doses, with Mn-NFs of x = 0.3 showing optimal cellular uptake. MH studies demonstrated significant cancer cell death at AMF intensities of around 30 kA/m, with increased effectiveness following static magnetic field pre-alignment. Conclusions: The results highlight Mn-NFs, particularly those with a Mn content of x = 0.3, as promising candidates for MH-based lung cancer therapy, combining high heating efficiency, biocompatibility, and effective intracellular uptake. Further studies are needed to validate their therapeutic potential in vivo. Full article

Background/Objectives: Work-related musculoskeletal disorders (WMSDs) have been found to be the leading factor in disabilities and absenteeism among workers. Despite their growing numbers, WMSD prevalence and risk factors among food delivery riders remain underexplored. Given the high WMSD prevalence among motorcyclists and the rising road traffic accidents (RTAs) among delivery riders in Malaysia, a cross-sectional study was conducted to identify the determinants of WMSDs among this neglected group. Methods: A self-reported questionnaire consisting of sociodemographic factors, work-related factors, and a validated Malay-translated Standardised Nordic Musculoskeletal Questionnaire (M-SNMQ) was used to evaluate the WMSD symptoms and related factors among 191 food delivery riders in Eastern Peninsular Malaysia. An ergonomic risk assessment using the Rapid Entire Body Assessment (REBA) method and whole-body vibration (WBV) measurement was also conducted to elicit the WMSD risk and vibration exposure among the riders. The determinants of WMSDs were analysed using multiple logistic regression using SPSS 20.4. Results: This study revealed a high prevalence of WMSDs (74.9%) among food delivery riders in Eastern Peninsular Malaysia. Furthermore, three factors were found to be significantly associated with WMSDs among riders, namely the increasing average working days (aOR = 2.00; 95% CI = 1.34, 2.98; p = 0.001), whole-body vibration (WBV) above the exposure action value (EAV) limit (aOR = 2.71; 95% CI = 1.13, 6.53; p = 0.026), and not exercising before work (aOR = 21.63; 95% CI = 7.45, 62.79; p < 0.001). Conclusions: Targeted interventions are essential to mitigate ergonomic risks and enhance rider safety. Occupational health policies should prioritise pre-work exercise and WBV exposure reduction to minimise musculoskeletal strain. Future longitudinal studies are needed to evaluate the long-term impact of these risks on riders’ health. Full article

This paper presents whole-body vibration prediction in an agricultural tractor based on selected operational parameters using machine learning. Experiments were performed using a Landini Powerfarm 100 model tractor on farmlands and service roads located at the Osijek School of Agriculture and Veterinary Medicine. The methodology adhered to the HRN ISO 5008 protocols for establishing test surfaces, including a smooth 100 m track and a rugged 35 m track. Whole-body vibrational exposure assessments were carried out in alignment with the HRN ISO 2631-1 and HRN ISO 2631-4 guidelines, which outline procedures for evaluating mechanical oscillations in occupational settings. The obtained whole-body vibration data were divided into three datasets (one for each axis) and processed using linear regression as a baseline and compared against three machine learning models (gradient boosting regressor; support vector machine regressor; multi-layer perception). The most accurate machine learning model according to the R² metric was the gradient boosting regressor for the x-axis (R²: 0.98) and the y-axis (R²: 0.98), and for the z-axis (R²: 0.95), the most accurate machine learning model was the SVM regressor. The application of machine learning methods indicates that machine learning models can be used to predict whole-body vibrations more accurately than linear regression. Full article

Bumblebees (Bombus spp.) are pivotal to sustaining biodiversity and enhancing agricultural productivity, thanks to their unique pollination mechanisms, including “buzz pollination”. Their ability to operate under adverse conditions—low temperatures and dim light—makes them essential for crops like tomatoes, peppers, and blueberries. This study synthesizes the ecological and behavioral traits of bumblebees, such as floral fidelity and vibration pollination, and explores their indispensable role in agricultural systems, particularly in greenhouse and open-field farming. By employing a bibliometric analysis, this review identifies critical research trends and emerging frontiers in bumblebee pollination, including their integration with precision agriculture technologies like remote sensing and artificial intelligence. Notably, there is increasing research on the impacts of climate change on bumblebee behavior and distribution, with studies focusing on how environmental stressors influence pollination efficiency. Additionally, the potential of using bumblebees in agroecological approaches and their role in enhancing crop resilience in changing climates are gaining traction. Moreover, it highlights the challenges posed by habitat loss, pesticide exposure, and climate change, emphasizing the urgency of conservation efforts. This study proposes interdisciplinary strategies for optimizing bumblebee pollination services, aiming to support sustainable agriculture and strengthen ecosystem resilience. The findings provide theoretical and practical insights for leveraging bumblebee pollination to achieve global food security and ecosystem stability. Full article

This paper presents research on the impact of vibrations on the hand–arm and body system of agricultural tractor operators as ergonomic indicators in relation to certain operational parameters. The measurements were conducted on a LANDINI POWERFARM 100 tractor on agricultural production areas and access roads of the Agricultural and Veterinary School in Osijek. The measurements followed the ISO 5008:2015 standard, which describes the creation of test tracks: a smooth track of 100 m in length and a rough track of 35 m in length. Body vibration measurements were conducted according to the prescribed standards HRN ISO 2631-1: 1999/A1:2019 and HRN ISO 2631-4:2010. Hand–arm system vibration measurements were performed according to the prescribed standards HRN ISO 5349-1:2008 and HRN ISO 5349-2:2008/A1:2015. After the measured data were processed, a three-factor analysis of variance was performed, where some operational parameters were designated as A—agrotechnical surfaces (6 types), B—tractor speed (6 speeds), and C—tire air pressure (3 pressures), along with multiple regression analysis and the AHP (analytical hierarchical process). This research determined that none of the measured hand–arm system vibrations exceeded the warning (2.5 ms⁻²) or limit (5 ms⁻²) values of daily exposure. Furthermore, vibrations affecting the operator’s body in the x-axis at higher speeds and pressures C2 and C3, in the y-axis at higher speeds and pressures C1 and C2, and in the z-axis at the highest speed and pressures C1 and C2 were found to exceed the daily exposure warning value of 0.5 ms⁻². It was concluded that the operator’s health is at risk, and it is recommended that the seat’s air suspension system be inspected to prevent further complications in a timely manner. Full article

To quantify the effect of frequency-range-specific hand–arm vibration (FRS-HAV) exposure on the risk of musculoskeletal disorders of the upper limb (UMSDs), we performed an analysis among the study sample of the German Hand–Arm Vibration Study. In total, 206 cases and 609 controls were included in this analysis. Cases were new patients with UMSDs. Controls were a random sample of people with compensable occupational injuries. Standardized personal interviews were performed among cases and controls. In addition to leisure activities and comorbidities, detailed work histories were obtained from all participants. To quantify FRS-HAV exposures, a database of vibration measurements of over 700 power tools was used. This database allows detailed quantification of vibration exposure over long periods of time. A dose–response relationship between FRS-HAV exposure and UMSDs was quantified using conditional logistic regression analyses. After adjustment for relevant confounders, consistent and statistically significant exposure–response relationships were observed between cumulative vibration exposure and UMSDs. The effect of vibration exposure on the risk of UMSDs is mainly concentrated in the frequency range ≤ 50 Hz. This suggests that the current ISO frequency-weighting curve for quantifying hand–arm vibration exposure is reasonable and can be used for vibration-related risk assessment, especially for musculoskeletal disorders. Full article

Various metal-based nanomaterials have been the focus of research regarding their use in controlling pests and diseases and in improving crop yield and quality. In this study, we synthesized via a solvothermal procedure pegylated zinc-doped ferrite (ZnFer) NPs and characterized their physicochemical properties by X-ray diffraction (XRD), vibrating sample magnetometry (VSM), thermogravimetric analysis (TGA), FT-IR and UV–Vis spectroscopies, as well as transmission electron microscopy (TEM). Subsequently, their impact on tomato photosynthetic efficiency was evaluated by using chlorophyll a fluorescence imaging analysis to estimate the light energy use efficiency of photosystem II (PSII), 30, 60, and 180 min after foliar spray of tomato plants with distilled water (control plants) or 15 mg L⁻¹ and 30 mg L⁻¹ ZnFer NPs. The PSII responses of tomato leaves to foliar spray with ZnFer NPs showed time- and dose-dependent biphasic hormetic responses, characterized by a short-time inhibitory effect by the low dose and stimulatory effect by the high dose, while at a longer exposure period, the reverse phenomenon was recorded by the low and high doses. An inhibitory effect on PSII function was observed after more than ~120 min exposure to both ZnFer NPs concentrations, implying a negative effect on PSII photochemistry. We may conclude that the synthesized ZnFer NPs, despite their ability to induce hormesis of PSII photochemistry, have a negative impact on photosynthetic function. Full article

The present paper investigates the comparative impact of vibrations on operator safety for two diesel and electric agricultural tractors under real operating conditions. Vibrations were measured using four triaxial accelerometers installed at critical points, including the seat base, backrest, floor, and operator’s head. Tests were conducted on two comparable tractor models, a diesel New Holland TCE 50 and an electric prototype TE-0, across four types of terrains (concrete, grass, uneven agricultural road, and plowed land) and at two working speeds (5 km/h and 10 km/h). The root mean square (RMS) accelerations, seat-to-head transmissibility, and isolation efficiency were calculated in compliance with ISO 2631 standards to evaluate the effects on operator health and comfort. The results showed superior vibration isolation efficiency for the electric tractor, particularly within the critical frequency range of 4–12 Hz, where human health risks are most significant and a better isolation efficiency of 98%, significantly reducing operator exposure to harmful vibrations. These findings highlight the potential of electric tractors to improve operator comfort, safety, and long-term health in agricultural applications. Full article

In this work, we report the properties of molybdenum disulfide (MoS₂) thin films deposited on the p-type silicon substrate using RF magnetron sputtering. The structural, vibrational and morphological properties of MoS₂ thin films were investigated using the Raman spectroscopy, X-ray diffraction technique (XRD), atomic force microscope (AFM) and scanning electron microscope (SEM). Raman spectroscopy result showed the appearance of broad E¹_2g and A_1g Raman peaks even without DC biasing the substrate and becomes sharp and distinct when the substrate is DC biased at 60 V. Post-deposition annealing in sulfur ambient resulted in sharp and distinct Raman E¹_2g and A_1g peaks confirming the formation of MoS₂ thin film and improved Mo-S bonding on the top surface. X-ray diffraction spectra of the samples validates the formation of MoS₂ thin film with the appearance of [002] XRD peak, when the substrates are biased. Improved morphological effects with the reduction in nano-sized defects, advent of continuous film and low surface rms roughness value of 0.872 nm, were observed on samples deposited with substrate biasing and post sulfur annealing. A back-gated thin film transistor was fabricated with Al as source-drain contacts and MoS₂ as the semiconducting channel. The fabricated transistor exhibited p-type transfer characteristics with threshold voltage of −3.8 V. As a result of annealing and ambient exposure, MoO₃ fragments on the top of thinned MoS₂ layer resulted in extraction of hole from MoS₂, resulting in the p-type behavior in the fabricated thin film transistor. The combination of XRD analysis, Raman measurements and EDS data of the film confirmed MoO₃ inclusions in the MoS₂ thin film. Full article

Mechanical shaking enables efficient harvesting of olives, especially in hilly regions where automated farming is not feasible. This study delves into branch and olive detachment modeling to enhance the efficiency of a hand-held branch shaker. Shaking time, forces, accelerations, olive detachment forces and harvesting efficiency were experimentally measured. The fruit maturity index affected the force needed to detach the olive, with the highest value for olives at the C0 stage of maturity (5.93 N). No difference emerged among the tested shaking times (6 s and 12 s), neither in terms of harvest efficiency (mean 81.17%) nor in terms of damage (rate of 5.30). Therefore, the lower time was considered the most appropriate. Multibody and a Finite Element (FE) models were developed to investigate the branch response and the olive detachment condition. The stresses predicted by the FE harmonic analysis (about 8 MPa), based on the excitation force and shaking frequency measured during the tests, was in line with the measured olive detachment forces (3 to 8 MPa). The shaking frequency and the average branch acceleration in proximity to the shaker hook were 15 Hz and 50m/s², respectively. Further studies could focus on the impact of the branch shaker on operator health, particularly risks from prolonged vibration exposure. Full article

Background/Objectives: The movement and vibration of the body’s soft tissues during dynamic exercise are mechanisms that attenuate force from ground impacts. However, repeated exposure to such vibrations over time can contribute to the development of lower-body soreness and/or injuries. The previous literature has established the benefit of compression garments for the minimisation of soft tissue movement during running, though little is known about this mechanism during other forms of dynamic exercise. The current study aimed to investigate the effect of compression tights on lower-body soft tissue movement during jumping, sprinting and change-of-direction tasks typical of those found in team sports. Methods: In a randomised crossover design, twelve recreationally active males (age 26 ± 2 years) completed countermovement jumps, drop jumps from 45 cm, 10 m straight line sprints and change-of-direction tasks wearing either commercially available sports compression tights or regular exercise tights. Marker-based motion capture was used to quantify soft tissue displacement at the thigh and calf and lower-body kinematic variables during the exercise tasks. Results: No significant (p < 0.05) differences were observed between conditions for soft tissue displacement at the thigh and calf and performance variables for all tasks. There were significant (p = 0.003) differences in peak knee flexion and hip flexion during the 10 m sprint and change-of-direction task between conditions; however, effect sizes were unclear. Conclusions: Compression tights do not appear to influence soft tissue movement or performance during sports-specific forms of locomotion but may alter some kinematic aspects of sprinting and change-of-direction tasks compared with regular exercise tights. Full article

Seawater ballast tanks in vessels are subject to severe service conditions caused by repeated filling/emptying, as well as temperature variation. Consequently, relatively thick, barrier-type coatings are used for corrosion protection of their internals. These are generally formulated with solvent-based epoxy binders and contain a range of flake pigments designed to limit environmental entry. Here, we report on a detailed study of damage processes in order to understand the mechanisms of failure after hygro-thermal cyclic corrosion testing. Similar formulations were cured using variant phenalkamine cross-linkers. Visual observation after corrosion testing shows minimal changes and no sign of corrosion damage. However, high-resolution analytical microscopy and nanoscale tomography reveal the onset of microstructural and chemical damage processes inside the coating. Thus, kaolin and talc pigments in the coating remained stable under hygro-thermal cycling; however, dolomite and barium sulphate dissolved slightly, causing voids. Galvanic protection of the substrate by aluminium flake pigments was disproven as no electrical connection was evident. Vibrational spectroscopy revealed a decrease in residual epoxy functionality after exposure for the coating cured with the more stable phenalkamine. This was correlated with an increase in glass transition temperature (Tg) and no observable corrosion of aluminium flakes. In contrast, the less stable phenalkamine cross-linker caused the binder Tg to decrease and aluminium flakes and substrate corrosion to become evident. Full article