Search Results (922)

Halarachne halichoeri mites are respiratory parasites of pinnipeds that have been recorded from different locations around the world, but not from the coast of Argentina. In this study, the presence of H. halichoeri on the southern elephant seal, Mirounga leonina, is documented for the first time in the Argentinean mainland, specifically in the Paraná River on the Buenos Aires coast. A total of 4130 adult and immature mites (90.4% larvae, 0% nymphs, 9.2% females and 0.4% males) were collected from the nose and nasopharyngeal cavity of a stranded juvenile male during a necropsy. The species was identified using scanning electron microscopy (SEM) and stereomicroscope photography, and the morphological characteristics of the females and males are shown. Also, images of the male are shown for the first time, with observable details of traits. We also propose a method for simple sex recognition. Finally, we provide a revision of global records of geographic distribution of H. halichoeri in wild marine mammals. The present record of occurrence of the species H. halichoeri in Argentina expands our knowledge about the distribution area known to date for this species of marine parasite. Full article

This paper presents a case study on an ultra-deep excavation in a reclaimed area supported by servo steel struts, addressing the limited case-specific data on deformation behavior under such complex geological conditions. Comprehensive monitoring of the pit structure and surrounding environment was performed throughout construction. Results highlight significant time-dependent deformation due to the rheological behavior of artificial fill and soft soil, with metro tunnel displacement during suspension phases contributing up to 29% of the total. Servo steel struts, via active axial force compensation, reduced maximum diaphragm wall displacement by 24%, ground settlement by 29%, and pipeline settlement by 46% compared to conventional supports. Integrated measures, including bottom-sealed diaphragm walls, isolation piles, and grouting curtains, successfully confined tunnel deformation within 5.4 mm, complying with strict safety criteria. A strong linear correlation between tunnel and wall displacements was observed, enabling a predictive envelope model for deformation. This study underscores the efficacy of servo steel struts in controlling excavation-induced deformation in reclaimed areas and offers practical insights for designing and managing ultra-deep excavations in similar challenging settings. Full article

This article focuses on developing and characterizing one-part rock-based geopolymer slurries using Brazilian rock precursors for well construction and plugging and abandonment (P&A) applications. The study presents the fluid-state and solid-state properties of these geopolymers, as well as X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM), to understand the microstructure of the precursors and the reaction level. The effect of temperature and pressure on the development of compressive strength was investigated. By altering these parameters, the study aimed to examine the impact of various conditions on the strength development of the geopolymer material. Technological tests were conducted following API RP 10B-2. Compressive strength tests were conducted to determine early strength development and thickening time. Post-curing Rietveld refinement by XRD was performed to examine the microstructure and reactivity. Finally, fluid-state properties were also assessed, including thickening time and viscosity. The strength development of geopolymers is observed to be time- and temperature-dependent, as shown by UCS results. The final product has a dense structure, and its long-term performance will require evaluation to determine its sealing capability and volume change as a barrier material. The results highlight the novelty of employing locally available Brazilian rock precursors in one-part geopolymer formulations and provide a scientific basis for their potential application as sustainable alternatives to conventional cements in well construction and abandonment. Full article

The global agricultural sector faces escalating labor shortages and post-harvest losses, particularly in delicate crop handling. This study introduces an integrated soft robotic harvesting system addressing these challenges through four key innovations. First, a low-cost, high-yield fabrication method for silicone-based soft grippers is proposed, reducing production costs by 60% via compressive-sealing molds. Second, a decentralized IoT architecture with edge computing achieves real-time performance (42 fps to 73 fps) on affordable hardware (around $180 per node). Third, a lightweight vision pipeline combines handcrafted geometric features and contrast analysis for crop maturity assessment and gripper tracking under occlusion. Fourth, a Neo-Hookean-based statics model incorporating circumferential stress and variable cross-sections reduces tip position errors to 5.138 mm. Experimental validation demonstrates 100% gripper fabrication yield and hybrid feedforward–feedback control efficacy. These advancements bridge the gap between laboratory prototypes and field-deployable solutions, offering scalable automation for perishable crop harvesting. Full article

With the IMO’s 2050 decarbonization target, hydrogen is a key zero-carbon fuel for shipping, but the lack of systematic risk assessment methods for hydrogen-powered marine propulsion systems (under harsh marine conditions) hinders its large-scale application. To address this gap, this study proposes an integrated risk evaluation framework by fusing Failure Mode, Effects, and Criticality Analysis (FMECA) with the Fuzzy Analytic Hierarchy Process (FAHP)—resolving the limitation of traditional single evaluation tools and adapting to the dynamic complexity of marine environments. Scientific findings from this framework confirm that hydrogen leakage, high-pressure storage tank valve leakage, and inverter overload are the three most critical failure modes, with hydrogen leakage being the primary risk source due to its high severity and detection difficulty. Further hazard matrix analysis reveals two key risk mechanisms: one type of failure (e.g., insufficient hydrogen concentration) features “high severity but low detectability,” requiring real-time monitoring; the other (e.g., distribution board tripping) shows “high frequency but controllable impact,” calling for optimized operations. This classification provides a theoretical basis for precise risk prevention. Targeted improvement measures (e.g., dual-sealed valves, redundant cooling circuits, AI-based regulation) are proposed and quantitatively validated, reducing the system’s overall risk value from 4.8 (moderate risk) to 1.8 (low risk). This study’s core contribution lies in developing a universally applicable scientific framework for marine hydrogen propulsion system risk assessment. It not only fills the methodological gap in traditional evaluations but also provides a theoretical basis for the safe promotion of hydrogen shipping, supporting the scientific realization of the IMO’s decarbonization goal. Full article

The school-age period is a crucial time for the integrated development of cognitive and motor functions. Literature highlights that physical activity enhances executive functions, including visuospatial working memory (VSWM). In light of this evidence, this study investigated the effects of a school-based coordinative motor intervention on VSWM and gross motor skills in primary school children. An experimental research trial was conducted involving 184 children aged 9–10 years (mean age = 9.5 years, SD = 0.50 years), with 51.1% girls, divided into an experimental group (EG; n = 110), and a control group (CG; n = 74). Randomisation was performed at the class level via sealed envelope extraction by an independent researcher, ensuring allocation concealment. Outcome assessors were blinded to group assignment. VMWM was assessed using BVS-Corsi-2, and gross motor skills were evaluated via the TGMD-3. The EG showed significant improvements in VSWM (Corsi Forward: p < 0.001, d = 1.12; Corsi Backward: p < 0.001, d = 1.40) and gross motor skills, including Total Gross Motor: p < 0.001, d = 1.58, as well as in locomotion (p < 0.001, d = 2.11) and ball skills score (p < 0.001, d = 1.34). These findings strongly endorse incorporating cognitively demanding physical activities into standard school programmes to support children’s overall development and demonstrate the practicality of implementing such programmes within existing educational settings. Full article

Maintaining an effective facial seal is critical for the performance of tight-fitting industrial respirators used in high-risk sectors such as mining, manufacturing, and construction. Traditional fit verification methods—Qualitative Fit Testing (QLFT) and Quantitative Fit Testing (QNFT)—are limited to periodic assessments and cannot detect fit degradation during active use. This study presents a real-time fit detection system based on embedded breath sensors and machine learning algorithms. A compact sensor module inside the respirator continuously measures pressure, temperature, and humidity, transmitting data via Bluetooth Low Energy (BLE) to a smartphone for on-device inference. This system functions as a multimodal biosensor: intra-mask pressure tracks flow-driven mechanical dynamics, while temperature and humidity capture the thermal–hygrometric signature of exhaled breath. Their cycle-synchronous patterns provide an indirect yet reliable readout of respirator–face sealing in real time. Data were collected from 20 healthy volunteers under fit and misfit conditions using OSHA-standardized procedures, generating over 10,000 labeled breathing cycles. Statistical features extracted from segmented signals were used to train Random Forest, Support Vector Machine (SVM), and XGBoost classifiers. Model development and validation were conducted using variable-size sliding windows depending on the person’s breathing cycles, k-fold cross-validation, and leave-one-subject-out (LOSO) evaluation. The best-performing models achieved F1 scores approaching or exceeding 95%. This approach enables continuous, non-invasive fit monitoring and real-time alerts during work shifts. Unlike conventional techniques, the system relies on internal physiological signals rather than external particle measurements, providing a scalable, cost-effective, and field-deployable solution to enhance occupational safety and regulatory compliance. Full article

Successful endodontic treatment relies on effective shaping, disinfection and obturation. Calcium silicate sealers such as BioRoot™ RCS show promise due to their bioactivity and sealing properties, but more clinical evidence using standardized protocols is needed. This observational clinical study aimed to assess periapical healing at 6 and 12 months following single-visit root canal treatment using BioRoot™ RCS with hydraulic condensation in teeth with irreversible pulpitis or apical periodontitis. Sixty-six teeth were treated using a standardized protocol: ProTaper Gold instrumentation, sonic-activated irrigation, and hydraulic condensation with gutta-percha cone and BioRoot™ RCS. Periapical healing was evaluated using the periapical index (PAI) at baseline, 6 months, and 12 months. Clinical success was defined as functional, asymptomatic teeth and a PAI ≤ 2. Statistical analysis included repeated measures of ANOVA and McNemar’s test. All 66 teeth remained asymptomatic and functional of 12 months, yielding a 100% survival rate. Clinical success was confirmed in 97% of cases. PAI scores decreased significantly over time (p < 0.001) in apical periodontitis cases. Single-visit endodontic treatment with BioRoot™ RCS and hydraulic condensation demonstrated excellent clinical and radiographic outcomes. This approach promotes resolution of apical periodontitis in non-vital cases and supports the preservation of periapical health in teeth initially diagnosed with irreversible pulpitis. Full article

The spotted seal (Phoca largha), the only pinniped species capable of natural breeding in Chinese waters, serves as a flagship species for the Bohai Sea and the Yellow Sea marine ecosystems. Changes in its population numbers are an important indicator of the status of the marine ecological environment. However, when using traditional monitoring methods, such as telescope inspections and routine unmanned aerial vehicle (UAV) photography, it is difficult to accurately grasp the changes in spotted seal populations. Here, we document the use of infrared imaging with a UAV to facilitate round-the-clock monitoring of spotted seal numbers in a protected area. This approach revealed that late night and early morning (22:00–05:00) were peak times for their haul-out activity, with a maximum count of 166. This provides a new idea for the investigation and monitoring of marine mammals and the protection of marine ecosystems. Full article

This study addresses the challenge of low working gas ratios in China’s underground gas storage (UGS) facilities by optimizing geomechanical evaluations to enable safe pressure increases and capacity expansion. Through mini-fracturing tests conducted at the Liaohe Gas Storage Group, a cross-validated analytical framework was established, integrating the square-root-of-time, Geomechanical (G) function, and flow-back pressure–volume methods. This framework enables precise determination of the dynamic maximum safe pressure, effectively balancing storage efficiency against the risks of fracture and fault activation. The results indicate that the minimum horizontal stress is 37% higher in the caprock than in the reservoir, confirming the integrity of the natural stress barrier. A mere 0.39% discrepancy in interpretation results validates the consistency of the methodology. The derived three-dimensional (D) in situ stress model reveals that the upper sandstone section exhibits 15–20% higher horizontal stress than deeper intervals, acting as a secondary barrier against fracture propagation. Theoretically, we propose a ‘stress differential gradient sealing’ mechanism to explain the buffering effects observed in the sandstone–mudstone transition zone. Practically, we developed a standardized testing protocol for complex geological conditions, which achieved a 15% increase in the maximum safe operating pressure at the Liaohe facility. This study provides critical insights for optimizing gas storage operations. Full article

Coatings based on the eutectic alloy Fe–TiB₂–CrB₂ were obtained by detonation spraying and subjected to pulsed plasma treatment. Comprehensive studies of the microstructure, phase composition, and mechanical and electrochemical properties of the coatings were carried out using SEM, TEM, and XRD methods. The initial coatings are characterized by a typical lamellar structure with interlamellar pores and defects. After pulsed plasma treatment, pronounced compaction of the surface layer, grain refinement, and sealing of interlamellar voids and cracks are observed. The thickness of the modified zone is about 15–30 μm, and the structure becomes fine-grained and more uniform. According to XRD and TEM data, the main boride phases (TiB₂, CrB₂) remain stable, while the intensity of γ-Fe decreases and weak Cr₂₃C₆ peaks appear, indicating phase stabilization and diffusion hardening. After treatment, the microhardness of the near-surface zone increases from ~14 GPa to 17–18 GPa, confirming the strengthening effect. Electrochemical tests showed an increase in corrosion resistance: the corrosion potential shifts to the positive side by approximately 0.15 V, and the corrosion current density decreases by almost two times. Thus, the use of pulsed plasma treatment significantly improves the density, phase stability, hardness, and corrosion resistance of Fe–TiB₂–CrB₂ detonation coatings, making this duplex approach promising for use in conditions of intense wear and exposure to aggressive environments. Full article

Efficient and secure inter-task communication (ITC) is critical in real-time embedded systems, particularly in security-sensitive architectures. Traditional ITC mechanisms in Real-Time Operating Systems (RTOSs) often incur high latency from kernel trapping, context-switch overhead, and multiple data copies during message passing. This paper introduces a zero-copy, capability-protected ITC framework for CHERI-enabled RTOS environments that achieves both high performance and strong compartmental isolation. The approach integrates mutexes and semaphores encapsulated as sealed capabilities, a shared memory ring buffer for messaging, and compartment-local stubs to eliminate redundant data copies and reduce cross-compartment transitions. Temporal safety is ensured through hardware-backed capability expiration, mitigating use-after-free vulnerabilities. Implemented as a reference application on the CHERIoT RTOS, the framework delivers up to 3× lower mutex lock latency and over 70% faster message transfers compared to baseline FreeRTOS, while preserving deterministic real-time behavior. Security evaluation confirms resilience against unauthorized access, capability leakage, and TOCTTO vulnerabilities. These results demonstrate that capability-based zero-copy ITC can be a practical and performance-optimal solution for constrained embedded systems that demand high throughput, low latency, and verifiable isolation guarantees. Full article

Objectives: Transvaginal Natural Orifice Transluminal Endoscopic Surgery (vNOTES) offers significant benefits in hysterectomy, including reduced postoperative pain, minimal scarring, and faster recovery. However, the cost and accessibility of surgical ports can be limiting factors. This study aimed to evaluate the feasibility, outcomes, and cost-effectiveness of using the Lagis LapBase Cap as an alternative port system in 107 vNOTES hysterectomy cases at a single institution. Methods: A retrospective analysis was conducted on 107 patients who underwent vNOTES hysterectomy between January 2017 and April 2022. Patients with benign gynecologic conditions and no suspected malignancy or deep infiltrating endometriosis were included. The Lagis LapBase Cap was used for access via an Alexis wound retractor. Surgical parameters—including operation time, estimated blood loss, and length of hospital stay—were analyzed by uterine weight, BMI, and obstetric history. Results: Of the 107 cases, 104 were completed using vNOTES, with only 3 conversions to laparoscopy. The average operation time was 88 min, and the mean estimated blood loss was higher in patients with larger uteri or BMI ≥ 24. Nulliparous women and those with a history of multiple cesarean sections also had longer operation times. There were no major complications, and most patients were discharged within three days postoperatively. Conclusions: The Lagis LapBase Cap is a practical and cost-efficient tool for vNOTES hysterectomy. It provides reliable sealing and instrument access, while maintaining favorable surgical outcomes. Patient selection based on uterine size, BMI, and delivery history may help optimize procedural efficiency. Full article

Background: The Sandwich technique is a commonly adopted method for reinforcing the dissected aortic wall during acute Type A aortic dissection (ATAAD) repair, using either felt or bovine pericardial strips. However, complications such as anastomotic bleeding, distal anastomotic new entry (DANE) and persistent false lumen (PFL) remain major challenges. This study evaluated and compared the sealing efficacy of felt versus pericardium in a human cadaver model. Methods: ATAAD was simulated in 20 fresh human cadavers. Repairs were performed using the sandwich technique with either felt (n = 10) or pericardium (n = 10), followed by end-to-end prosthetic graft anastomosis. Procedure time was recorded. Following the repair, the aortas were perfused at 160/90 mmHg using a glycerol-water solution to assess fluid leakage (mL), DANE and PFL. Results: Median leakage was significantly lower in the pericardium group (67.5 mL [IQR 40–198.8]) compared to the felt group (315 mL [IQR 285–445], p = 0.002). Procedure times were comparable between groups. DANE occurred in 20% (pericardium) and 30% (felt) of cases, while PFL was observed in 30% of cases in both groups; differences were not statistically significant. Conclusions: The superior sealing properties of pericardium in this study suggest a promising approach for reducing leakage in ATAAD repair. While rates of DANE and PFL were comparable, the advantage of pericardium was confined to leakage reduction. These findings highlight the need for further research to determine whether this experimental benefit translates into improved clinical outcomes. Full article

The process of exploiting hydrocarbon deposits is subject to many complications, some of which can make exploitation very difficult or impossible. These factors include damage to the wellbore zone by drilling fluid, which impedes the flow of reservoir fluid from the production zone to the well. This article presents the results of research conducted to develop drilling fluid compositions with the best possible ability to form a tight sealing sediment on the borehole wall. In addition to traditional carbonate blockers, modern organic agents were used as bridging agents. Research was conducted on the selection of the drilling fluid composition, the rheological parameters of which would ensure the suspension of the solid phase in the form of various types of blockers. After preparing the base drilling fluid, its composition was modified by adding different configurations of blockers. The sets of blockers added to the fluid varied in both chemical structure and particle size. Such modified fluids were then subjected to tests of technological properties, such as rheological parameters, API filtration, and pH. In the next stage, sealing tests of the filter cake formed by the tested fluids were carried out on the surface of the rock core using the PPT—Pore Pressure Transmission Test. Based on the obtained results, it can be concluded that the new type of organic blockers used allows the rapid formation of a tight filter cake on the borehole wall, and thus significantly reduces drilling fluid filtration. During PPT, the sediment formation time (t_pmax) for OB2 was 45 min; for the combination of OB1 and the carbonate inhibitor, it was 8 min; and for the carbonate inhibitor alone, it was 150 min. Full article