Combined uranium-series and electron spin resonance dating from the Pliocene fossil sites of Aves and Milo's palaeocaves, Bolt's Farm, Cradle of Humankind, South Africa.

Bolt's Farm is the name given to a series of non-hominin bearing fossil sites that have often been suggested to be some of the oldest Pliocene sites in the Cradle of Humankind, South Africa. This article reports the results of the first combined Uranium-Series and Electron Spin Resonance (US-ESR) dating of bovid teeth at Milo's Cave and Aves Cave at Bolt's Farm. Both tooth enamel fragments and tooth enamel powder ages were presented for comparison. US-ESR, EU and LU models are calculated. Overall, the powder ages are consistent with previous uranium-lead and palaeomagnetic age estimates for the Aves Cave deposit, which suggest an age between ~3.15 and 2.61 Ma and provide the first ages for Milo's Cave dates to between ~3.1 and 2.7 Ma. The final ages were not overly dependent on the models used (US-ESR, LU or EU), which all overlap within error. These ages are all consistent with the biochronological age estimate (<3.4->2.6 Ma) based on the occurrence of Stage I Metridiochoerus andrewsi. Preliminary palaeomagnetic analysis from Milo's Cave indicates a reversal takes place at the site with predominantly intermediate directions, suggesting the deposit may date to the period between ~3.03 and 3.11 Ma within error of the ESR ages. This further suggests that there are no definitive examples of palaeocave deposits at Bolt's Farm older than 3.2 Ma. This research indicates that US-ESR dating has the potential to date fossil sites in the Cradle of Humankind to over 3 Ma. However, bulk sample analysis for US-ESR dating is recommended for sites over 3 Ma.

Valuation of multi-dimensional health states with a "bolt-on": is there a shortcut?

OBJECTIVES: In order to use the EQ-5D questionnaire with bolt-on dimensions in economic evaluation studies, new value sets are needed. In this study, we explored the feasibility of a new approach called scaling factor model, which estimates bolt-on value sets using estimated EQ-5D dimensional weights. METHODS: We designed a two-arm study, inviting university students to value health states with and without bolt-on items using the composite time trade-off (cTTO) method. We selected 25 health states from an orthogonal array and added 5 mildest EQ-5D states in the design. In arm 1, EQ-5D without self-care and standard EQ-5D states were valued, and in arm 2, standard EQ-5D states and EQ-5D with vision were valued. By arm, we compared the mean observed values of health states with and without bolt-on item. Next, by arm, we estimated value sets for the EQ-5D with bolt-on item states using both standard model and scaling factor model. Model performances were compared in terms of prediction accuracy and correlation with likelihood-based mean values. RESULTS: Adding a fifth-level bolt-on to EQ-5D resulted in statistically lower values. This effect is consistent across two arms and bolt-on items. The scaling factor models outperformed the standard models in all statistics. CONCLUSIONS: The scaling factor model offers a methodologically viable and low-cost option for producing value sets for EQ-5D, supplemented with bolt-on items. Future studies should further test this method using other bolt-on items and relevant study populations.

Image-Based Bolt-Loosening Detection Using a Checkerboard Perspective Correction Method.

In this paper, a new image-correction method for flange joint bolts is proposed. A checkerboard is arranged on the side of a flange node bolt, and the homography matrix can be estimated using more than four feature points, which include the checkerboard corner points. Then, the perspective distortion of the captured image and the deviation of the camera position angle are corrected using the estimated homography matrix. Due to the use of more feature points, the stability of homography matrix identification is effectively improved. Simultaneously, the influence of the number of feature points, camera lens distance, and light intensities are analyzed. Finally, based on a bolt image taken using an iPhone 12, the prototype structure of the flange joint in the laboratory is verified. The results show that the proposed method can effectively correct image distortion and camera position angle deviation. The use of more than four correction points not only effectively improves the stability of bolt image correction but also improves the stability and accuracy of bolt-loosening detection. The analysis of influencing factors shows that the proposed method is still effective when the number of checkerboard correction points is reduced to nine, and the average error of the bolt-loosening detection result is less than 1.5 degrees. Moreover, the recommended camera shooting distance range is 20 cm to 60 cm, and the method exhibits low sensitivity to light intensity.

Prediction of Pre-Loading Relaxation of Bolt Structure of Complex Equipment under Tangential Cyclic Load.

Bolts have the advantages of simple installation and easy removal. They are widely applied in aerospace and high-speed railway traffic. However, the loosening of bolts under mixed loads can lead to nonlinear decreases in pre-loading. This affects the safety performance of the structure and may lead to catastrophic consequences. Existing techniques cannot be used to monitor the bolt performance status in time. This has caused significant problems with the safety and reliability of equipment. In order to study the relaxation law of bolt pre-loading, this paper carries out an experimental analysis for 8.8-grade hexagonal bolts and calibrates the torque coefficient. We also studied different loading waveforms, nickel steel plate surface roughnesses, tangential displacement frequencies, four different strengths and bolt head contact areas of the bolt, the initial pre-loading, and the effects of tangential cyclic displacement on pre-loading relaxation. This was done in order to accurately predict the degree of bolt pre-loading loosening under external loads. The laws are described using the allometric model function and the nine-stage polynomial function. The least squares method is used to identify the parameters in the function. The results show that bolts with a smooth surface of the connected structure nickel steel flat plate, high-frequency working conditions, half-sine wave, and a high-strength have better anti-loosening properties. Taking 5-10 cycles of cyclic loading as a boundary, the pre-loading relaxation is divided into two stages. The first stage is a stage of rapid decrease in bolt pre-loading, and the second stage is the slow decrease process. The performance prediction study shows that the allometric model function is the worst fitted, at 71.7% for the small displacement condition. Other than that, the allometric model function and the nine-stage polynomial function can predict more than 85.5% and 90.4%, which require the use of least squares to identify two and ten unknown parameters, respectively. The complexity of the two is different, but both can by better indicators than the pre-loading relaxation law under specific conditions. It helps to improve the monitoring of bolt loosening and the system use cycle, and it can provide theoretical support for complex equipment working for a long time.

Experimental Study on Durability and Bond Properties of GFRP Resin Bolts.

Glass fiber-reinforced polymer (GFRP) anchor bolts are a new type of high-performance nonmetallic anchor with significantly higher tensile strength, a lighter weight, better corrosion resistance, and a lower cost than steel bars. Therefore, exploring the durability and bonding performance of GFRP anchor systems is of great importance for the structural design of protective engineering, especially in coastal environments. However, insufficient research has been conducted on the durability of GFRP resin bolts in seawater conditions, with no universal standard on the pullout testing of GFRP bolts. To study the durability and bonding performance of GFRP resin bolts, durability experiments were conducted in this work using artificial seawater, and the pullout tests were conducted using a large-scale concrete platform with different compressive strengths (21.2, 40.8, and 61.3 MPa). The results of the durability experiments indicated that the strength variations of the GFRP rods and epoxy resin materials in artificial seawater environments were less than 5%. Subsequently, indoor pullout tests using steel tubes filled with epoxy resin were conducted, and the test results indicated a critical anchor length value. Pullout tests of the GFRP resin bolts embedded in large-scale concrete blocks were also conducted with different strengths. According to the test results, all GFRP resin bolts embedded in the three concrete blocks with different compressive strengths exhibited rod fracture failure. The failure mode was not controlled via the compressive strength of the concrete blocks due to the high bonding strength between the resin and the rod, as well as between the resin and the concrete. Therefore, this GFRP resin anchor system could fully utilize the tensile strength of GFRP rods. This research offers significant practical value in verifying the safety and reliability of GFRP resin bolts in corrosive marine service environments, and it contributes to the application and development of GFRP materials in the engineering field, serving as a valuable reference for the structural design and further study of GFRP bolts.

Signal Processing Using a Circular Sensor Array to Measure the Torsional Angle of a Bolted Joint.

This study presents a new approach to determining the preload force of bolted joints. The concept involves measuring the torsional angle without contact. For this purpose, we present a circular magnetic sensor array integrated into the torque wrench. The torsional angle in bolted joints depends on the dimensions of the screw and the materials used and is typically less than four degrees. For this reason, one requirement is a high angular resolution so that a continuous recording of the torsion angle is feasible during the assembly process. This can be achieved using the circular sensor array and adapted signal processing methods. Two signal processing approaches are utilized. First, the direct method uses the discrete Fourier transformation to calculate the rotation angle from the signal phase. This approach is robust to signal distortion and does not depend on signal amplitude. Second, the method with a learning phase employs Gaussian process regression to minimize the angle error. In an experiment, both approaches were applied within a test bench and showed promising results. The direct method demonstrated a very good angular resolution without training and calibration. For mobile and less-complex applications where a reference system is unavailable, the direct method is preferable. However, in complex measurement systems where reference systems can be utilized initially, significant enhancements to an excellent resolution can be achieved through prior training.

Captive Bolt Gun-Related Vascular Injury: A Single Center Experience.

This article investigates the clinical and radiological characteristics of captive bolt gun head injuries, a rare form of low-velocity penetrating brain injury. Eleven consecutive patients were included in the study. Vascular injuries and the rate of infection were systematically analyzed. Radiological findings reveal common bolt trajectories in the anterior cranial fossa, with identified risk factors for a poor outcome including trajectory crossing midline, hematocephalus, and paranasal sinus involvement. Only one patient had a good outcome. Despite meticulous microsurgical techniques, this study highlights often unfavorable clinical outcomes in captive bolt gun injuries, with vascular injury identified as a potential contributing risk factor for a poor outcome. Knowledge of variant vascular tree anatomy and corresponding vascular territory is important. To avoid potential vascular injuries, a complete removal of bone fragments was not always performed and it did not increase the rate of infection, challenging the conventional wisdom advocating for the complete removal of bone fragments. These findings contribute novel insights into captive bolt gun-related injuries, paving the way for further research.

Evolution characteristics and performance evaluation of extended end-plate joints with single and double side connections under cyclic loading.

Experimental studies were conducted on four extended end-plate joints subjected to cyclic loading at the column top, investigating the evolving patterns of the joints' mechanical performance. The paper provides a detailed analysis and discussion of the test joints' failure modes, ductility, stiffness degradation, and energy dissipation capacity. The Mann-Kendall (M - K) trend analysis tool was applied to the mechanical response curves, identifying key performance evolution points (evolution initiation point P and overall yield point Q). The trends in bolt forces, deformations, and strains at critical joints were effectively validated, revealing the transition of the energy system from quantitative to qualitative changes and the component's failure process from stability to instability. Additionally, based on the experimental joints' hysteresis curves and energy dissipation capacity, a theoretical hysteresis model was established to predict the joint's hysteresis curve and cumulative dissipated energy accurately. According to EC3 requirements, joints were classified as partially rigid connections. The experimental results of the initial rotational stiffness and plastic moment were further used to evaluate the calculated values in existing standards EN 1993-1-8, ANSI/AISC 358-16, and GB 51017-2017. The results indicate that extended end-plate connections possess sufficient strength, joint rotational stiffness, ductility, and energy dissipation capacity, making them suitable for seismic moment frames.

A novel anti-loosening bolt looseness diagnosis of bolt connections using a vision-based technique.

Bolt looseness detection is a common problem in engineering. Most vision-based detection techniques focus on diagnosing ordinary bolt looseness, i.e., the methods used for diagnosis are based only on the sidelines of nuts. These methods cannot be used for anti-loosening bolt looseness diagnosis because of the simultaneous rotation of screws and nuts. Therefore, a novel anti-loosening bolt looseness diagnosis method based on a vision-based technique is proposed in this paper. First, a regular hexagonal cap was installed on the screw, which can be used as a reference for the nut. Then, to automatically distinguish the hexagonal borders of the screw cap and nut, a new hexagonal border reconstruction algorithm is proposed. Furthermore, the relative rotation angles of the screw cap and nut hexagons can be determined using the sidelines of the reconstructed hexagonal borders of the screw cap and nut. Finally, a novel anti-loosening bolt looseness diagnosis method is established by using the relative rotation angle of the regular hexagonal borders of the screw cap and nut under initial status and loose status. A prototype flange node of the transmission tower was used for experimental verification. The results show that the proposed method can effectively detect the loosening angle of anti-loosening bolts.

The use of a penetrative captive bolt device during the killing of farmed saltwater crocodiles (Crocodylus porosus).

Killing of farmed saltwater crocodiles involve stunning with a penetrative captive bolt device, followed by a cut across the nape of the neck and physical destruction of the brain to ensure death. This study was a welfare-based assessment of the use of a penetrative captive bolt device in saltwater crocodiles, to determine whether it satisfies the criteria of a humane stunning method and can be regarded as a direct killing method without the need for the application of an adjunct method. Methods used were electroencephalogram (EEG), observation of post-stun behavior, and postmortem examination of gross pathology of the cranium and brain. 30 of 30 animals, demonstrated immediate and irreversible loss of consciousness. There was extensive damage to the brain in all animals, deemed to be inconsistent with cortical function and possible recovery. The CASH Special 0.22 penetrative captive bolt pistol (1.25 grain cartridge), applied to the top of the cranial plate, produced immediate and irreversible unconsciousness in all the animals studied. This method satisfies animal welfare expectations, providing crocodile processors with a technique that contributes to a humane killing process.

Exploring potential EQ-5D bolt-on dimensions with a qualitative approach: an interview study in Hong Kong SAR, China.

PURPOSE: The introduction of bolt-on dimensions in EQ-5D instruments is growing common, but most bolt-on studies have targeted the diseased population and obtained bolt-on from other existing Health-related Quality of Life (HRQoL) instruments. As the qualitative approach offers important evidence to support the consistency and design of the potential bolt-on items, this paper studies the Hong Kong SAR community's perception of the current EQ-5D-5 L instrument and identifies potential bolt-on via a qualitative approach. METHODS: A representative sample mix was recruited based on the age group, gender, and education level composition of the Hong Kong SAR community by quota sampling. Semi-structured interviews were conducted and the interviews were transcribed and coded to identify emergent and recurrent themes. RESULTS: Thirty interviews were conducted and the majority of the interviewees considered the EQ-5D-5 L insufficiently comprehensive to illustrate their HRQoL. While some key HRQoL aspects included in the EQ-5D matched with the community's HRQoL perception, respondents showed concern about the potential overlap of the existing HRQoL dimension, the optimal number or attributes, and the appropriateness of the EQ-VAS. Among the potential bolt-on dimensions that emerged, 'Sleep', 'Interpersonal Relationship', and 'Satisfaction' were the key potential bolt-on dimensions identified and emphasized in the interviews. CONCLUSIONS: The qualitative findings of the study illustrate the possible gap between EQ-5D-5 L measurements and community HRQoL perception, while the findings support the development of EQ-5D bolt-on dimensions in the target community with content and face validity.

Quantification of cooling effects on basic tissue measurements and exposed cross-sectional brain area of cadaver heads from Holstein cows > 30 mo of age.

Penetrating captive bolt (PCB) is the primary method of preslaughter stunning for cattle and is also used for on-farm euthanasia. The objective of this study was to quantify the impact of cooling on the soft tissue thickness, cranial thickness, total tissue thickness, and cross-sectional brain area of cadaver heads collected from mature (> 30 mo of age) dairy cows following the application of a PCB stun in a frontal placement. Hide-on cadaver heads were obtained from culled dairy cows (N = 37) stunned in a frontal location using a handheld PCB device (Jarvis Model PAS-Type C 0.25R Caliber Captive Bolt, Long Bolt) at a commercial slaughter establishment. Following transport to the University of Wisconsin-River Falls, heads were split at midline along the bolt path by a bandsaw and then underwent FRESH, CHILL24, CHILL48, and CHILL72 refrigeration treatments. The FRESH treatment involved images collected immediately after splitting each head, the CHILL24 treatment involved images collected after 24 h of refrigeration, the CHIL48 treatment involved images collected after 48 h of refrigeration, and the CHILL72 treatment involved images collected after 72 h of refrigeration. Measurements of soft tissue thickness, cranial thickness, total tissue thickness, and cross-sectional brain area were recorded for each refrigeration treatment. Soft tissue thickness did not differ caudal to (P = 0.3751) or rostral to (P = 0.2555) the bolt path. Cranial thickness did not differ caudal to (P = 0.9281) or rostral to (P = 0.9051) the bolt path. Total tissue thickness did not differ caudal to (P = 0.9225; FRESH: 24.77 mm, CHILL24: 23.93 mm, CHILL48: 24.27 mm, CHILL72: 42.30, SE: 0.86) or rostral to (P = 0.8931; FRESH: 24.09 mm, CHILL24: 23.99, CHILL48: 24.26, CHILL72: 24.43 mm, SE: 0.79 mm) the bolt path. Cross-sectional brain area was not different (P = 0.0971) between refrigeration treatments (FRESH: 9,829.65 ±â€…163.87 mm2, CHILL24: 10,012.00 ±â€…163.87 mm2, CHILL48: 9,672.43 ±â€…163.87 mm2, CHILL72: 10,235.00 ±â€…166.34 mm2). This study demonstrated that FRESH tissue parameters can be determined from cattle cadaver heads refrigerated for 24, 48, or 72 h.

Movements after Captive Bolt Stunning in Cattle and Possible Animal- and Process-Related Impact Factors-A Field Study.

Movements in cattle after captive bolt stunning cause problems in the slaughter process and lead to uncertainties in assessing stunning effectiveness. The objective of this study was to categorize and quantify these movements and determine animal- and process-related impact factors, as well as connections to stunning effectiveness and shooting position. In total 2911 cows, heifers, and bulls (dairy, beef, and crossbreeds) were examined (mean age 3.02 years). Movements from landing until at least four minutes after sticking were recorded by action cams (Apeman® A100). Nine movement categories were defined ("kicking hind limb", "twitching", "bending and stretching hind limb", "lifting and bending forelimb", "body arching laterally", "body arching ventrally", and "arching backwards"). According to the movement severity, a score was assigned to each category. The scores were summed, either for certain process intervals, e.g., LANDING (ejection from the stunning box), HOISTING, or STICKING, or for the total time between LANDING and end of the FOURTH MINUTE OF BLEEDING (sum score). Statistical analysis (ANOVA) was performed on the scores. Only 6.6% of cattle showed no movement. Most movements occurred during STICKING and FIRST MINUTE OF BLEEDING, occurring rarely up to 8 min after sticking. While cows moved most at LANDING, bulls and heifers moved more if all process intervals were considered. The sum score was highest in German Angus, Charolais, and Limousin and lowest in Brown Swiss and Simmental. The score at LANDING was highest in German Angus and Black Holstein. The use of pneumatic stunners and an increase in bolt-exit length significantly reduced movements. No impact of stunning effectiveness on movements was found, but only 19 cattle showed reduced effectiveness.

Optimization of anti-loosening bolt based on double thread mechanism: Development of ground rolling die and effect of thread accuracy on loosening resistance.

We have devised innovative anti-loosening bolts with a double thread-mechanism (denoted DTB-IIC) composed of coaxial single and multiple coarse threads. In this study, we first developed a high-speed and high-precision grinding system for dedicated thread rolling dies of the DTB-IIC. Compared to conventional electro-discharge machining dies, ground dies significantly reduced processing time and costs, and achieved more than 10 times higher durability in thread rolling tests. Comparative Junker vibration loosening tests based on an ISO standard were conducted on several types of DTB-IICs. The amount of backlash δ between the inner multiple-thread nut and DTB-IIC bolt has a great effect on the initial drop of the bolt axial preload, and the rolled DTB-IIC with a relatively small δ secured a residual axial load rate of ≥85%, which satisfies the rating-1 of good self-locking behavior. A 3D FEM model was employed to simulate the initial loosening process in the Junker test, and the analytical results agreed well with the experimental ones by adjusting δ appropriately. Both experimental and analytical results indicate that the high loosening resistance of DTB-IIC is due to the synergistic effect of the interference mechanism of two types of nuts and the jammed locking state.

Thermal and Mechanical Stress Analysis in Aircraft Hybrid Panels with Multi-Bolt Joints.

This study investigates the thermal stress and bolt load distribution in a hybrid panel structure of an aircraft mechanical joint under extreme temperatures. The hybrid panel structure comprises two aluminum alloy splices, six T-shaped composite stringers, and two composite skins, secured together with 96 bolts. This study analyzed the strain induced by thermal stress on composite materials and metals within the structure across temperatures, employing temperature environment tests ranging from room temperature to -54 °C, alongside a carrying capacity test at -54 °C. Furthermore, a three-dimensional simulation model of the panel structure was developed, incorporating considerations for contact, metal elastoplasticity, and the progressive damage failure of composite materials. This model facilitated the determination of thermal stress and bolt load distribution patterns. The results indicate a strong consistency between the finite element analysis outcomes and the experimental data. Temperature variations exacerbate the uneven distribution of bolt loads, concentrating the load near the edges of the hybrid structure while diminishing it in the center. The bolt load distribution parallel to the mechanical load direction forms an "M" shape, with a maximum load magnitude of approximately 31 kN. Perpendicular to the mechanical load, the bolt load undergoes significant changes, especially at the edges, reaching a maximum of about 20 kN, which warrants attention. The bolt-load distribution of the structure with the increase in mechanical load at -54 °C tends to be consistent with that at room temperature.

Numerical analysis of underground tunnel deformation: a case study of Midroc Lega-Dembi gold mine.

Undertakings in underground mining are often complicated, particularly in situations where geotechnical conditions are not favorable. This study investigates the collapse of tunnels at the Lega-Dembi gold mine in Southern Ethiopia, an area characterized by weak talc formations. The persistent deformation of tunnels poses a threat to the safety of workers and mining operations. In this study, a numerical method that combines continuum and discontinuum approaches is employed to analyze tunnel failures. Additionally, the study evaluates the effect of geotechnical parameters on tunnel deformation, considering various support systems. The results indicate that a combination of rock bolts and shotcrete is effective in mitigating tunnel deformation. Furthermore, the study identifies the geological strength index and unconfined compressive strength as the most influential parameters on tunnel deformation. The findings also suggest appropriate support systems for managing underground instability and enhancing safety measures in weak geological formations.

Testing the Psychometric Properties of 9 Bolt-Ons for the EQ-5D-5L in a General Population Sample.

OBJECTIVES: We aimed to assess the psychometric performance and added value of 9 existing bolt-ons (breathing problems, cognition, hearing, self-confidence, skin irritation, sleep, social relationships, tiredness, and vision) for the EQ-5D-5L in a general population sample. METHODS: The EQ-5D-5L, 9 bolt-ons, SF-6Dv1, Patient-Reported Outcomes Measurement Information System (PROMIS)-29+2, PROMIS Global Health, and Satisfaction with Life Scale were completed in an online cross-sectional survey among a general adult population sample in Hungary (n = 1587). The following psychometric properties were tested for the EQ-5D-5L + bolt-on(s): ceiling, divergent and convergent validity, structural validity, known-group validity, and explanatory power. RESULTS: Adding sleep (30%), tiredness (24%), or vision (21%) substantially reduced the ceiling of the EQ-5D-5L (41%). Cognition, sleep, social relationships, and tiredness correlated with corresponding PROMIS and SF-6D items (rs = ǀ0.32ǀ - ǀ0.73ǀ). All bolt-ons, except cognition and self-confidence, loaded on a different factor from the EQ-5D-5L dimensions. Breathing, hearing, skin irritation, and vision significantly improved known-group validity in relevant health condition groups. The sleep bolt-on improved known-group validity in 9 of 13 chronic health conditions. Tiredness had the largest impact on explaining EQ VAS score variance in 8 of 13 conditions. Hearing and vision improved the ability of the EQ-5D-5L to capture declining health with age, whereas self-confidence and social relationships were valuable for mental health assessment. CONCLUSIONS: This study established the validity of multiple bolt-ons for the EQ-5D-5L and highlights the usefulness of including relevant bolt-ons in population-based and patient surveys. Our findings inform the further development of these bolt-ons and the bolt-on item selection for clinical studies.

Structural health monitoring of jacket-type support structures in offshore wind turbines: A comprehensive dataset for bolt loosening detection through vibrational analysis.

This dataset provides a comprehensive collection of vibrational data for the purpose of structural health monitoring, particularly focusing on the detection of bolt loosening in offshore wind turbine jacket foundations. The data set comprises 780 comma-separated values (CSV) files, each corresponding to specific experimental conditions, including various structural states of the wind turbine's support structure. These states are systematically varied considering three main aspects: the amplitude of a white noise (WN) signal, the type of bolt damage, and the level at which damage has occurred. The data were meticulously collected using eight triaxial accelerometers (PCB R Piezotronic model 356A17), strategically placed at different locations on a scaled-down replica of an offshore jacket-type wind turbine. This setup facilitated the acquisition of detailed vibrational data through a National Instruments' data acquisition (DAQ) system, comprising six input modules (NI 9234 model) housed in a chassis (cDAQ model). The white noise signal, simulating wind disturbance at the nacelle, was produced by a modal shaker and varied in three amplitudes (0.5, 1, and 2), directly proportional to the induced vibration in the wind turbine. The dataset uniquely captures the vibrational behaviour under different scenarios of bolt loosening in the turbine's foundation. The conditions include a healthy state (bolts tightened to 12 Nm) and various degrees of loosening (bolts loosened to 9 Nm, 6 Nm, and completely absent), examined at four distinct levels of the turbine's base structure. This granular approach offers a nuanced view of how varying degrees of bolt loosening impact the vibrational characteristics of the structure. The value of this dataset lies in its potential for wide-ranging applications in the field of structural health monitoring. Researchers and engineers can leverage this data for developing and testing new methodologies for early damage detection and progressive damage assessment in offshore wind turbines. The dataset's comprehensive coverage of damage scenarios makes it a valuable resource for the validation and enhancement of existing damage detection algorithms. Furthermore, the dataset can serve as a benchmark for comparing the efficacy of different vibrational analysis techniques in the context of wind turbine maintenance and safety. Its application is not only limited to wind turbines but can extend to other structures where bolt integrity is critical for operational safety. This dataset represents a significant contribution to the field of structural health monitoring, providing a detailed and practical resource for enhancing the reliability and safety of offshore wind turbines and similar structures.

Retained Intracerebral Depth Electrode after Stereotactic Electroencephalography Monitoring: A Case Report.

Stereotactic electroencephalography (SEEG) is an increasingly popular surgical modality for localizing the epileptogenic zone. Robot-guided stereotactic electrode placement has been covered in Japan by National Health Insurance since 2020. However, several surgical devices, such as the anchor bolt (a thin, hollow, metal shaft that serves as a guide screw or fixing for each electrode), have not been approved. A 14-year-old female who underwent SEEG for intractable epilepsy and required additional surgery to remove a retained depth electrode from the skull after the SEEG monitoring was finished. She had uncontrolled focal seizures consisting of nausea and laryngeal constriction at the onset. After a comprehensive presurgical evaluation, robot-guided stereotactic electrode implantation was performed to evaluate her seizures by SEEG. Nine depth electrodes were implanted through the twist drill hole. The electrodes were sutured to her skin for fixation without anchor bolts. When we attempted to remove the electrodes after 8 days of SEEG monitoring, one of the electrodes was retained. The retained electrode was removed through an additional skin incision and a small craniectomy under general anesthesia. We confirmed narrowing of the twist drill hole pathway in the internal table of the skull due to osteogenesis, which locked the electrode. This complication might be avoided if an anchor bolt had been used. This case report prompts the approval of the anchor bolts to avoid difficulty in electrode removal. Moreover, approval of a depth electrode with a thinner diameter and more consistent hardness is needed.

Crossbow Injuries: Predictors of Mortality.

INTRODUCTION: Crossbow injuries are rare but carry significant morbidity and mortality, and there is limited evidence in the medical literature to guide care. This paper reviews the case reports and case series of crossbow injuries and looks for trends regarding morbidity and mortality based on the type of arrow, anatomic location of injury, and intent of injury. METHODS: Multiple databases were searched for cases of crossbow injuries and data were abstracted into a spreadsheet. Statistics were done in SPSS. RESULTS: 358 manuscripts were returned in the search. After deduplication and removal of nonclinical articles, 101 manuscripts remained. Seventy-one articles describing 90 incidents met the inclusion criteria. The mean age was 36.5 years. There were 10 female and 79 male victims. Fatality was 36% for injuries by field tip arrows and 71% for broadhead arrows, p = .024. Assaults were fatal in 84% of cases, suicides in 29%, and accidental injuries in 17%, p < .001. Mortality was similar for wounds to the head and neck (41%), chest (42%), abdomen (33%), extremities (50%), and multiple regions, p = .618. CONCLUSIONS: Crossbows are potentially lethal weapons sold with fewer restrictions than firearms. Injuries caused by broadhead arrows are more likely to be fatal than injuries from field tip arrows. The anatomic location of injury does not correlate with fatality. More than half of crossbow injuries are due to attempted suicide, with a high case-fatality rate.