Sharp Tool Research Articles

Effects of cutting tool geometry on material removal of a gradient nanograined CoCrNi medium entropy alloy.

CoCrNi medium-entropy alloys (MEAs) have attracted extensive attention and research because of their superior mechanical properties, such as higher ductility, strength, and toughness. This study uses molecular dynamics (MD) simulations to investigate the cutting behavior of a gradient nanograined (GNG) CoCrNi MEA. Moreover, it explores the influence of relative tool sharpness and rake angle on the cutting process. The results show that an increase in the average grain size of the GNG samples leads to a decrease in the average resultant cutting force, as predicted by the Hall-Petch relationship. The deformation behavior shows that grain boundaries are crucial in inhibiting the propagation of strain and stress. As the average grain size of the GNG sample increases, the range of shear strain distribution and average von Mises stress decreases. Moreover, the cutting chips become thinner and longer. The subsurface damage is limited to a shallow layer at the surface. Since thermal energy is generated in the high grain boundary density, the temperature of the contact zone between the substrate and the cutting tool increases as the GNG size decreases. The cutting chips removed from the GNG CoCrNi MEA substrates will transform into a mixed structure of face-centered cubic and hexagonally close-packed phases. The sliding and twisting of grain boundaries and the merging of grains are essential mechanisms for polycrystalline deformation. Regarding the cutting parameters, the average resultant force, the material accumulation, and the chip volume increase significantly with the increase in cutting depth. In contrast to sharp tools, which mainly use shear deformation, blunt tools remove material by plowing, and the cutting force increases with the increase in cutting-edge radius and negative rake angle.

Infrared Spectroscopy Can Differentiate Between Cartilage Injury Models: Implication for Assessment of Cartilage Integrity

In order to improve the ability of clinical diagnosis to differentiate articular cartilage (AC) injury of different origins, this study explores the sensitivity of mid-infrared (MIR) spectroscopy for detecting structural, compositional, and functional changes in AC resulting from two injury types. Three grooves (two in parallel in the palmar-dorsal direction and one in the mediolateral direction) were made via arthrotomy in the AC of the radial facet of the third carpal bone (middle carpal joint) and of the intermediate carpal bone (the radiocarpal joint) of nine healthy adult female Shetland ponies (age = 6.8 ± 2.6 years; range 4–13 years) using blunt and sharp tools. The defects were randomly assigned to each of the two joints. Ponies underwent a 3-week box rest followed by 8 weeks of treadmill training and 26 weeks of free pasture exercise before being euthanized for osteochondral sample collection. The osteochondral samples underwent biomechanical indentation testing, followed by MIR spectroscopic assessment. Digital densitometry was conducted afterward to estimate the tissue's proteoglycan (PG) content. Subsequently, machine learning models were developed to classify the samples to estimate their biomechanical properties and PG content based on the MIR spectra according to injury type. Results show that MIR is able to discriminate healthy from injured AC (91%) and between injury types (88%). The method can also estimate AC properties with relatively low error (thickness = 12.7% mm, equilibrium modulus = 10.7% MPa, instantaneous modulus = 11.8% MPa). These findings demonstrate the potential of MIR spectroscopy as a tool for assessment of AC integrity changes that result from injury.

Impact of coating and microstructure on wear resistance of tool steels for wood cutting: a novel approach to quantification and analysis of wear-related damages

Squaring, a wood transformation process, is an operation which consists of introducing the logs into a squaring machine which then uses sharp tools to cut the wood into pieces with high surface quality. Tool steels used in this process experience significant wear, damaging the wood surface and hence leading to substantial scrape rate. This study investigates the wear resistance of three tool steels specifically designed for wood cutting applications: modified AISI A8, modified steels with 0% and 1% tungsten, and powder metallurgy prepared W360 steel. Furthermore, the influence of a PVD coating on the wear resistance of the three alloys was investigated. ASTM G65 abrasive wear tests were conducted using the dry sand/rubber wheel abrasion test. A methodology using a non-contact 3D measurement system and specialized software was developed, allowing for a thorough quantitative assessment of the wear of these steels. The results revealed that the coated A8mod + 1%W steel exhibits the best resistance among the coated steels. Despite the excellent intrinsic resistance of W360 steel, the coating did not provide a significant improvement for this steel, showing only a 10% reduction in wear. Microstructural analysis revealed that the predominant wear mechanisms were abrasion and impact. The relative performance of each steel was quantified and is reported. Field trials conducted under actual cutting conditions, indicate the superiority of W360 steel in terms of resilience to wear and impacts compared to other tested alloys, while confirming the effectiveness of surface treatments in mitigating material wear. However, A8 steel modified with 1% tungsten exhibits increased wear under coating.

Experimental investigation on extrinsic size effect in micro-orthogonal cutting of commercial aluminium alloy

The achievable precision in micro-machining is constrained by a phenomenon known as the size effect. The edge radius of the tool significantly influences the size effect leading to non-proportional scaling of process performance. The process becomes unscalable below a certain ratio of uncut chip thickness to edge radius termed as critical relative tool sharpness (RTS). Despite extensive studies on the size effect associated with non-linear process performance, very limited studies have focused on the critical RTS range. In the present study, orthogonal cutting experiments were conducted on a commercial aluminium alloy (Al6060) with different cutting-edge radiuses in the RTS range of 0.5 to 0.01. Extensive analysis of the morphology of the chips and tool-work material adherence has been carried out and correlated with the observed size effect on surface integrity. One of the key findings in this study was the size effect in the chips with respect to the chip curl radius and pitch. Between RTS 0.5 and 0.09, an increase in chip curl and pitch is observed, followed by a sharp fall up to RTS 0.07. In addition, another notable phenomenon was the formation of dual-layered chips with deformed layer on the rake side and lamellae like features on the free side. Furthermore, size effect was observed in surface roughness, surface hardness and flank adherence. In summary, the present investigation offers a comprehensive understanding of the size effect within the critical RTS range elucidating its multifaceted impact on micro-cutting.

Factors Influencing Occupational Health and Safety among Nursing Students in Their Clinical Placements: A Cross-Sectional Study.

Occupational health and safety aims to promote and maintain optimal physical, mental, and social health for workers in their occupations. Within Saudi Arabia, adequate information must be gathered to address the various factors influencing occupational health and safety among nursing students to minimize occupational health hazards and ensure a safe clinical environment. This cross-sectional study was conducted in Riyadh, Saudi Arabia, between April and September 2023, involving 150 nursing students. Data collection included questions to gather sociodemographic information, and contained an instrument assessing the participants' knowledge of occupational health and safety and evaluation of risk control in clinical environments. Blood and other bodily fluids, workplace violence, needle-stick injuries, and injuries caused by sharp instrument tools were identified as the most prevalent occupational risks among the participants. Most nursing students were aware of occupational health and safety, with a high level of compliance with occupational health and safety measures and personal protective equipment use. We also identified a statistically significant correlation between occupational health and safety knowledge and risk control evaluation among nursing students. To ensure a safe and beneficial clinical training area, student nurses must complete extensive occupational health and safety courses before moving to clinical areas to reduce potential hazards that may affect their lives.

Modelling cutting force for turning AISI 304 stainless steel with PVD-AlTiN coated, PVD-AlTiN coated-microblasted, and MTCVD-TiCN/Al2O3 coated tools

ABSTRACT Stainless steel is challenging to machine, and to avoid any negative consequences, it is essential to comprehend the cutting forces. With this view, this study has developed a cutting force model for turning AISI 304 stainless steel with the most preferred PVD-AlTiN coated (C-type), PVD-AlTiN coated-microblasted (CMB), and MTCVD-TiCN/Al2O3 coated carbide tools (MTCVD). Empirical models are developed to predict the chip thickness ratio, the normal shear angle, and sharp tool cutting forces. Studies showed the reduction in forces with the cutting speed for C-type, CMB, and MTCVD tools was 12–20%, 11–32%, and 6–29%, respectively. However, the corresponding increases with the feed and depth of cut were 60–134%, 125–146%, and 97–178%; 76–186%, 55–384%, and 14–274%, respectively. Additionally, a cutting force model considering the tool wear effect is developed for MTCVD tools, which exhibited lower tool wear compared to other tools. The study accurately predicted sharp tool and worn tool cutting forces, showing good quantitative agreement with experimental results with an average error of less than 10%. However, some discrepancies were observed beyond the flank wear length of 0.2 mm. It was due to the chipping of the coating layers and the pitting of the substrate from the nose area.

Intrabulbar, Intraorbital and Intracranial Perforating Eye Injury with Foreign Body: A Case Report

Ocular trauma is a significant cause of preventable blindness and visual impairment worldwide. Eye globe perforation can happen due to work with sharp tools or different particles that are spread during work with metals, wood, and other solid substances.We present the case of a 14-year-old male patient admitted as an urgent case at the Ophthalmology Department in 2014 due to a perforating eye injury with a foreign body – a 7 cm rusty metallic nail in the right eye. The X-ray of the orbit revealed that the foreign body had penetrated the eyelid, the eye eyeball, and through the orbit and its posterior wall, penetrated the skull and 2 cm in the brain. Under general anesthesia, we performed the anterior chamber lavage, excision of the prolapsed iris, and pupilloplasty. The anterior chamber was reconstructed using a saline solution (0.9% NaCl) and air. The patient was treated conservatively with antibiotics and steroids for 10 days; there were no signs of wound filtration, hypotonia, or endophthalmitis. Due to the limited resources for the posterior segment surgery, the patient was referred to another center for pars plana vitrectomy (PPV) after 10 days of hospitalization in the Department of Ophthalmology at the University Clinical Center of Kosovo. After PPV with silicon oil and cataract surgery, the patient could see the light and its projections (BCVA = L+P+). We followed up on the patient until September 2022, there were no signs of bulbus atrophy, and the visual acuity remained the same, BCVA = L+P+. The correct diagnosis and treatment at the right time play a leading role in achieving one of the main goals of surgical treatment of perforating eye injuries, which is the preservation of the anatomical structure and the physiology of the eye.

Personalized decision-making for aneurysm treatment of aneurysmal subarachnoid hemorrhage: development and validation of a clinical prediction tool

BackgroundIn patients with aneurysmal subarachnoid hemorrhage suitable for endovascular coiling and neurosurgical clip-reconstruction, the aneurysm treatment decision-making process could be improved by considering heterogeneity of treatment effect and durability of treatment. We aimed to develop and validate a tool to predict individualized treatment benefit of endovascular coiling compared to neurosurgical clip-reconstruction.MethodsWe used randomized data (International Subarachnoid Aneurysm Trial, n = 2143) to develop models to predict 2-month functional outcome and to predict time-to-rebleed-or-retreatment. We modeled for heterogeneity of treatment effect by adding interaction terms of treatment with prespecified predictors and with baseline risk of the outcome. We predicted outcome with both treatments and calculated absolute treatment benefit. We described the patient characteristics of patients with ≥ 5% point difference in the predicted probability of favorable functional outcome (modified Rankin Score 0–2) and of no rebleed or retreatment within 10 years. Model performance was expressed with the c-statistic and calibration plots. We performed bootstrapping and leave-one-cluster-out cross-validation and pooled cluster-specific c-statistics with random effects meta-analysis.ResultsThe pooled c-statistics were 0.72 (95% CI: 0.69–0.75) for the prediction of 2-month favorable functional outcome and 0.67 (95% CI: 0.63–0.71) for prediction of no rebleed or retreatment within 10 years. We found no significant interaction between predictors and treatment. The average predicted benefit in favorable functional outcome was 6% (95% CI: 3–10%) in favor of coiling, but 11% (95% CI: 9–13%) for no rebleed or retreatment in favor of clip-reconstruction. 134 patients (6%), young and in favorable clinical condition, had negligible functional outcome benefit of coiling but had a ≥ 5% point benefit of clip-reconstruction in terms of durability of treatment.ConclusionsWe show that young patients in favorable clinical condition and without extensive vasospasm have a negligible benefit in functional outcome of endovascular coiling – compared to neurosurgical clip-reconstruction – while at the same time having a substantially lower probability of retreatment or rebleeding from neurosurgical clip-reconstruction – compared to endovascular coiling. The SHARP prediction tool (https://sharpmodels.shinyapps.io/sharpmodels/) could support and incentivize a multidisciplinary discussion about aneurysm treatment decision-making by providing individualized treatment benefit estimates.

Influence of cutting edge microgeometry on the cutting forces when machining difficult-to-cut materials

The paper presents research investigating the influence of cutting tools microgeometry on the cutting forces when milling difficult-to-cut materials. Austenitic stainless steel AISI 316L and nickel alloy Inconel 718 were machined with cemented carbide tools with various cutting edge rounding size while measuring the cutting forces during the process. From the standpoint of milling difficult-to-cut materials lowering the cutting forces load on the tool can be difficult to achieve without significant reduction of cutting parameters. Previous research into the cutting edge microgeometry suggests that modification of the cutting edge of milling tools can substantially extend the effective tool life, reduce cutting forces in the process and ensure higher quality of the machined surface. Results of long term wear tests of tools with cutting edge rounding sizes of 15, 30 and 45 µm are compared to the results of a sharp unprepared cutting tool, and the results of each machined material are also compared. Possible influence of cutting edge radius on the process for both materials was tested for cutting conditions constituting finishing operation. The most effective cutting edge radius size differed between the materials, with 15 µm rounding performing the best for AISI 316L and the sharp unprepared tool performing the best for the Inconel 718 alloy.

Work Safety and Safety Devices in Brazilian Wood Sawmills for the Improvement of Working Conditions

Workplace safety is essential to ensure the health and integrity of the worker. Sawmills are known for high risk and severe accidents, especially involving circular saws, tenoners and jointers, which can, however, be prevented through the use of personal protective equipment (PPE), employee training, and safety measures on machines and equipment. The aim of this study was to present a compilation of the data presented in the literature about the main risks in sawmills, regulatory standards, the construction of a safety system, and the safety devices to be used. To choose the best safety methods, it is crucial to evaluate the types of risks present. Among the most common risks in sawmill machinery are mechanical, electrical, thermal, noise-induced, vibration-induced, caused by materials and substances, and disregarding of ergonomic principles. To reduce these risks, sawmills should have action plans that comply with regulatory standards, such as the use of PPE, machinery and equipment protection, demarcation of danger zones, workplace cleanliness, and operator training. Safety devices used in sawmills help reduce accidents and should be chosen based on machine’s use, the nature and frequency of access, types of risks, and the probability and severity of injury. For circular saws, risks can be minimized through the use of basic protections such as a splitter and guards, in addition to a push device for wood pieces. Tenoners and jointers present higher risks with sharp tools in contact with body parts, protective guarding in hazardous areas is recommended. In all cases, the use of personal protective equipment is essential.

Hukum Najis Mughallazah dan Kaedah Sertu Menurut Pandangan Empat Mazhab

Samak and sertu are terms related to the purification process in Islam. In the Islamic society in Malaysia, there is a misconception about the terms samak and sertu and the use of both terms in the purification of impurity. This misconception arises from a lack of understanding of the terms samak and sertu. Therefore, this article aims to explain the difference between the terms samak and sertu and the use of both terms. To achieve the aforementioned objectives, this study is based on an analysis of the content of fiqh books, scholarly articles, and fatwa on international and national rankings. For the analysis of Arabic books, the search of the terms al-dhabghu and ghasala is used. Meanwhile, the terms samak and sertu in the Malaysian Islamic Progress Office (JAKIM) guide. This data is then analyzed based on the views of the four madhhabs that are muktabar in fiqh. The results show that samak is the process of cleaning an animal's skin of impurities for a specific purpose with a sharp tool. While sertu is the process of cleaning the affected part of mughallazah faeces (dogs, pigs and their offspring) with the help of water and soil. The cleaning method of samak and sertu is different from the other two. The meaning of samak and sertu should be understood, as they were agreed upon for cleaning and hygiene.

Konsep Samak dan Sertu: Satu Perbandingan Menurut Perspektif Islam

Samak and sertu are terms related to the purification process in Islam. In the Islamic society in Malaysia, there is a misconception about the terms samak and sertu and the use of both terms in the purification of impurity. This misconception arises from a lack of understanding of the terms samak and sertu. Therefore, this article aims to explain the difference between the terms samak and sertu and the use of both terms. To achieve the aforementioned objectives, this study is based on an analysis of the content of fiqh books, scholarly articles, and fatwa on international and national rankings. For the analysis of Arabic books, the search of the terms al-dhabghu and ghasala is used. Meanwhile, the terms samak and sertu in the Malaysian Islamic Progress Office (JAKIM) guide. This data is then analyzed based on the views of the four madhhabs that are muktabar in fiqh. The results show that samak is the process of cleaning an animal's skin of impurities for a specific purpose with a sharp tool. While sertu is the process of cleaning the affected part of mughallazah faeces (dogs, pigs and their offspring) with the help of water and soil. The cleaning method of samak and sertu is different from the other two. The meaning of samak and sertu should be understood, as they were agreed upon for cleaning and hygiene.

Naïve, adult, captive chimpanzees do not socially learn how to make and use sharp stone tools

Although once regarded as a unique human feature, tool-use is widespread in the animal kingdom. Some of the most proficient tool-users are our closest living relatives, chimpanzees. These repertoires however consist primarily of tool use, rather than tool manufacture (for later use). Furthermore, most populations of chimpanzees use organic materials, such as sticks and leaves, rather than stones as tools. This distinction may be partly ecological, but it is also important as chimpanzees are often used as models for the evolution of human material culture, the oldest traces of which consist of manufactured sharp stone tools (so-called “flakes”). Thus, examining the conditions (if any) under which chimpanzees may develop flake manufacture and use can provide insight into the drivers of these behaviours in our own lineage. Previous studies on non-human apes’ ability to make and use flakes focused on enculturated apes, giving them full demonstrations of the behaviour immediately, without providing social information on the task in a stepwise manner. Here we tested naïve, captive chimpanzees (N = 4; three potentially enculturated and one unenculturated subject) in a social learning experimental paradigm to investigate whether enculturated and/or unenculturated chimpanzees would develop flake making and use after social information of various degrees (including a human demonstration) was provided in a scaffolded manner. Even though social learning opportunities were provided, neither the unenculturated subject nor any of the potentially enculturated subjects made or used flakes, in stark contrast to previous studies with enculturated apes. These data suggest that flake manufacture and use is outside of our tested group of captive chimpanzees’ individual and social learning repertoires. It also suggests that high levels of enculturation alongside human demonstrations (and/or training) may be required before captive chimpanzees can develop this behaviour.

Determination of the Tool Wear using Cutting Force in Face Milling of Ti-6Al-4V under High Pressurized Cooling Conditions

In this study, plain and profile cutting operations were carried out in Ti-6Al-4V material with sharp and worn tools. In the experiments, the cutting speed was 90 [m/min], the feed rate was 0.1 [mm/tooth], and the pressure of the applied coolant was changed to 6, 100, 200, 300 bar, respectively. Haar wavelet was applied to the Fx force signals recorded during the experiments and decomposition was made at Level 5. As a result of the analysis of the obtained CA5 wavelet coefficients with the receiver operating characteristic (ROC) curve analysis, the limit values were determined to separate the worn tool from the unworn tool. In this way, it will be possible to stop the machine at the desired wear value.

Extended TODIM method based on VIKOR for quality evaluation of higher education scientific research management under interval-valued Pythagorean fuzzy sets

Scientific research management is an important component of university management and an important guarantee for the sustainable operation of universities. A mature scientific research management system is a sharp tool to promote the discipline construction and comprehensive strength improvement of universities. Therefore, colleges and universities should actively explore new concepts, models, and mechanisms for scientific research management while continuously improving their own educational quality. Based on the analysis of the current situation of university scientific research management in China, it is of great significance to explore effective ways to improve the quality of university scientific research management in the new era. The quality evaluation of higher education scientific research management in entrepreneurship undergraduate colleges is a classical MAGDM problems. Recently, the TODIM and VIKOR method has been used to cope with MAGDM issues. The interval-valued Pythagorean fuzzy sets (IVPFSs) are used as a tool for characterizing uncertain information during the quality evaluation of higher education scientific research management in entrepreneurship undergraduate colleges. In this manuscript, the interval-valued Pythagorean fuzzy TODIM-VIKOR (IVPF-TODIM-VIKOR) method is built to solve the MAGDM under IVPFSs. In the end, a numerical case study for quality evaluation of higher education scientific research management in entrepreneurship undergraduate colleges is given to validate the proposed method.

Long-Read Sequencing Identified a Large Novel δ/β-Globin Gene Deletion in a Chinese Family

Objective. Increasingly rare thalassemia has been identified with the advanced use of long-read sequencing based on long-read technology. Here, we aim to present a novel δ/β-globin gene deletion identified by long-read sequencing technology. Methods. Enrolled in this study was a family from the Quanzhou region of Southeast China. Routine blood analysis and hemoglobin (Hb) capillary electrophoresis were used for hematological screening. Genetic testing for common α- and β-thalassemia was carried out using the reverse dot blot hybridization technique. Long-read sequencing was performed to detect rare globin gene variants. Specific gap-polymerase chain reaction (gap-PCR) and/or Sanger sequencing were further used to verify the detected variants. Results. None of the common α- and β-thalassemia mutations or deletions were observed in the family. However, decreased levels of MCV, MCH, and abnormal Hb bands were observed in the family members, who were suspected as rare thalassemia carriers. Further, long-read sequencing demonstrated a large novel 7.414 kb deletion NG_000007.3:g.63511_70924del partially cover HBB and HBD globin genes causing delta-beta fusion gene in the proband. Parental verification indicated that the deletion was inherited from the proband’s father, while none of the globin gene variants were observed in the proband’s mother. In addition, the novel δ/β-globin gene deletion was further verified by gap-PCR and Sanger sequencing. Conclusion. In this study, we first present a large novel δ/β-globin gene deletion in a Chinese family using long-read sequencing, which may cause δβ-thalassemia. This study further enhances that long-read sequencing would be applied as a sharp tool for detecting rare and novel globin gene variants.

Postoperative Radiotherapy to Abdominal and Pelvic Lymphatic Drainage Area for Stage III Epithelial Ovarian Cancer: A Sharp Tool to Prolong Disease-Free Survival Time

For patients with stage III epithelial ovarian cancer, there are limited studies on the effects of postoperative adjuvant radiotherapy (RT) after standard cytoreductive surgery (CRS) and full treatment of first-line adjuvant chemotherapy (CT). The aims of our study were to assess the therapeutic efficacy and toxicity of our special postoperative radiotherapy to abdominal and pelvic lymphatic drainage area for stage III epithelial ovarian cancer patients. We retrospectively collected patients with stage III epithelial ovarian cancer after CRS and full-course adjuvant chemotherapy. The CT+RT group patients were treated with intensity modulated radiotherapy (IMRT) to abdominal and pelvic lymphatic drainage area (which has been shown to be an alternative to whole abdominal radiotherapy (WART) both on the basis of clinical result and dosimetric verification from our prior study). The CT group data was obtained from the PUMCH's electronic medical record analytical database between 2010 and 2020. A propensity score matching analysis was performed 1:2 between CT+RT group and CT group. A total of 132 patients with median follow-up of 73.9 months (9.1-137.7 months) were included (44 and 88 for the CT+RT and CT groups, retrospectively). The baseline characteristics of age, histology, level of CA12-5, surgical staging, residual tumor, courses of adjuvant CT, and courses to reduce CA12-5 to normal were all balanced. The median disease-free survival (DFS) time, 5-year overall survival (OS), and local recurrence free survival (LRFS) of CT+RT group and CT group were 100.0 months versus 25.9 months (p = 0.020), 69.2% versus 49.9% (p = 0.002), 85.9% versus 50.5% (p = 0.020), respectively. Distant metastasis was still the primary reason (57.6%), and local failure rate was 42.3%, the local recurrence rate was significantly lower in CT+RT group, compared with CT group (13.6% versus 45.5%, p = 0.016). In terms of toxicity, CT+RT group mainly presented with acute hematological toxicities, with no statistically significant difference with CT group when compared with grade III intestinal adverse effects (3/44 versus 6/88, p = 0.480). This report demonstrates that long-term disease-free survival could be achieved in stage III epithelial ovarian cancer patients treated with IMRT preventive radiation to abdominal and pelvic lymphatic area. Compared with CT group, DFS and OS were significantly prolonged and adverse effects were acceptable.

Analisis Factor-Faktor Penyebab Kecelakaan Kerja Penggunaan Benda Tajam Atau Mesin pada Pemanen Sawit

Indonesia is a country with vast agricultural areas and the fertility of its soil is undisputed. This makes Indonesia a rich country in terms of agricultural products, especially oil palm plantations. Oil palm plantations have many advantages, especially since oil palm is a raw material that plays a strategic role in the country's economic development. However, this also avoids the risk of occupational injuries that threaten plantation workers, especially in the area of palm oil harvesting. Workplace accidents can be caused by activities involving the use of sharp tools and machinery such as dodos, egereks, ganks, axes and axes. The purpose of this study was to analyze the factors leading to occupational injuries associated with the use of sharp tools and machinery in oil palm harvesters. The results of this study indicate that there are several risk factors for workplace injury when sharps and machinery are used in oil palm harvesters, including worker knowledge level, use of personal protective equipment (PPE), and adherence to standards. indicates that there is Having it suggests that there is merit. Instruction manual (SOP)

Investigation of the rate-mediated form-function relationship in biological puncture

Puncture is a vital mechanism for survival in a wide range of organisms across phyla, serving biological functions such as prey capture, defense, and reproduction. Understanding how the shape of the puncture tool affects its functional performance is crucial to uncovering the mechanics underlying the diversity and evolution of puncture-based systems. However, such form-function relationships are often complicated by the dynamic nature of living systems. Puncture systems in particular operate over a wide range of speeds to penetrate biological tissues. Current studies on puncture biomechanics lack systematic characterization of the complex, rate-mediated, interaction between tool and material across this dynamic range. To fill this knowledge gap, we establish a highly controlled experimental framework for dynamic puncture to investigate the relationship between the puncture performance (characterized by the depth of puncture) and the tool sharpness (characterized by the cusp angle) across a wide range of bio-relevant puncture speeds (from quasi-static to sim 50 m/s). Our results show that the sensitivity of puncture performance to variations in tool sharpness reduces at higher puncture speeds. This trend is likely due to rate-based viscoelastic and inertial effects arising from how materials respond to dynamic loads. The rate-dependent form-function relationship has important biological implications: While passive/low-speed puncture organisms likely rely heavily on sharp puncture tools to successfully penetrate and maintain functionalities, higher-speed puncture systems may allow for greater variability in puncture tool shape due to the relatively geometric-insensitive puncture performance, allowing for higher adaptability during the evolutionary process to other mechanical factors.

Risk Assessment of Operating Room Occupational Hazards Using Failure Modes and Effects Analysis (FMEA)

Background: The operating room is one of the most risky parts of the hospital. All employed personnel are exposed to occupational hazards. This study aimed to assess and control the risk of occupational hazards in urology surgeries using the technique of analysis of error states and its effects in the operating room. Methods: In this cross-sectional study, data were collected through observation of common operating room processes, background checks and documents, and focus group discussion. Data analysis was in accordance with the failure modes and effects analysis (FMEA) method based on risk priority number (RPN). Results: Considering 16 common operating room processes, there were 23 potential error modes of which 5 of them were identified as unacceptable and high risk. These five items included "working with sharp tools with RPN8/311", "working under high pressure and risky conditions with RPN 292", "hand washing with RPN 254.6", "intubation/extubation/suction of secretions with RPN 213.2", and "working with radiation equipment with RPN 206.9". Conclusion: In case of unacceptable errors, corrective actions were presented in three areas of decreasing occurrence and severity and increasing the ability to detect errors. It is suggested that retraining courses be held to prevent errors, ensure the health of operating room personnel, and increase the quality of services.