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Abstract Accurate simulation of lightning‐induced overvoltage for overhead distribution lines is helpful to prevent lightning trip accidents. An electromagnetic return‐stroke model was used to represent lightning and then a 3D finite‐difference time‐domain (FDTD) method was adopted to simulate the lightning‐induced overvoltage on a distribution line without a field‐line coupling model. How lightning‐induced overvoltage behave for different ground conductivity and varying distance between the distribution line and the lightning channel was analysed. The results showed that the overvoltage waveforms at the centre point of the line corresponding to lightning strikes on the lossy ground and an ideal ground (σ = ∞) were similar; however, the peak amplitudes of the waveform were affected by soil conductivity at a close distance. The relationship between magnitude of the overvoltage and distance can be described by a second‐order exponential decay equation. Finally, the overvoltage calculated using the proposed model was compared with those obtained based on Agrawal's model and measurements made using the newly developed intelligent insulator on site. From these comparisons, it could be concluded that the FDTD method with the electromagnetic return‐stroke model produces reasonably accurate results of the attenuated oscillation waveform, which can better reproduce the overvoltage on operational distribution lines.

The biomedical application of biodegradable polymers for addressing bone-related diseases has garnered considerable attention in recent years. Advances in material technology have expanded the repertoire of materials suitable for orthopedic implants, with nanomaterials playing a pivotal role in replicating crucial surface properties akin to natural tissues. This comprehensive review explores the evaluation of bioactive glass ceramics, shedding light on their properties and applications. The synthesis of composites through composite manufacturing has emerged as a strategy to enhance biocompatibility and biomechanical characteristics. They are addressing challenges associated with conventional implants and nanomaterials, whether in the form of functional nano coatings or nanostructured surfaces, present opportunities to refine implant techniques. Novel developments in orthopedic biomaterials, such as smart biomaterials, porous structures, and 3D implants, offer stimuli-responsive behavior to achieve desired implant shapes and characteristics. Bioactive and biodegradable porous polymer/inorganic composite materials are explored for bone tissue engineering scaffolds, aiming to promote bone formation and regeneration. As a prospective direction, the integration of stem cells into scaffolds hints at the creation of next-generation synthetic/living hybrid biomaterials, displaying high adaptability in biological settings. This review establishes a foundation for nanotechnology-driven biomaterials by elucidating fundamental design factors crucial for orthopedic implant performance and their response to cell differentiation, proliferation, and adhesion.

Abstract Tropical cyclone (TC) intensification is influenced by environmental conditions, inner‐core dynamics, and interactions with upper‐ocean layers. Rapid intensification (RI) is a significant threat that is difficult to predict, prompting multiple institutions to collaborate. However, the accuracy still needs further improvements. It is well‐known that a warm upper ocean is conducive to RI, but the role of salinity stratification in this process is not well understood, particularly under different TC translation speeds. This study reveals that rapidly intensifying TCs are related to large salinity stratification, especially when TC moves slowly. To develop a predictive model, several machine learning (ML) algorithms are used, with the most appropriate parameters and weights for each algorithm being determined. Our final ML model, which incorporates salinity stratification as a predictor and TC translation speed as a weight parameter, demonstrates superior performance across various predictive metrics, including the probability of detection (POD), false alarm ratio (FAR), and Peirce Skill Score (PSS) over the Western North Pacific during 2004–2022 compared to the model without these two factors. The most significant enhancement is observed for intense RI episodes. The improvements are up to 14% for both in POD; 7% and 13% in FAR; and 19% and 16% in PSS for 12.75 and 15.3 m s−1 RI thresholds, respectively. These results highlight the importance of including salinity stratification as a new predictor and TC translation speed as a weighted parameter using ML techniques in RI prediction models.

Objective: To evaluate the clinical efficacy of internal limiting membrane (ILM) peeling combined with perimacular hole massage versus ILM flap insertion in the management of patients with idiopathic macular holes was conducted. Methods: 35 patients (total of 35 eyes) with idiopathic macular holes (with hole diameters ranging from 366 to 1430 μm) were divided into two groups—Group A consisted of 20 eyes that underwent pars plana vitrectomy (PPV) combined with ILM peeling and perimacular hole massage, while Group B comprised 15 eyes that underwent PPV combined with ILM flap insertion. Subsequent follow-up examinations were performed at 1 week, 1 month, and 3 months post-surgery. The study also involved a comparison of best corrected visual acuity (BCVA) and optical coherence tomography (OCT) classifications between both the patient groups. Results: The macular hole closure rates in Group A were 60 %, while in Group B, the closure rate was 93 %. There was significant difference in hiatus healing rate between the two groups (t = 4.843, p = 0.048). The difference in BCVA at 3 months post-operation between the two groups was statistically significant (t = 3.221, p = 0.003). Three months post-operatively, the BCVA in Group B demonstrated improvement compared to the pre-operative BCVA, with a statistically significant difference (p > 0.05). Three months post-operatively, the BCVA in Group A demonstrated improvement compared to the pre-operative BCVA, but this difference was not statistically significant (p > 0.05). Conclusion: The combination of PPV with ILM flap insertion demonstrates favorable therapeutic efficacy in the treatment of idiopathic macular holes, leading to improved visual acuity.

Recent advancements in orthopedic surgery have greatly improved the management of musculoskeletal disorders and injuries. This review discusses the latest therapeutic approaches that have emerged in orthopedics. We examine the use of regenerative medicine, including stem cell therapy and platelet-rich plasma (PRP) injections, to accelerate healing and promote tissue regeneration. Additionally, we explore the application of robotic-assisted surgery, which provides greater precision and accuracy during surgical procedures. We also delve into the emergence of personalized medicine, which tailors treatments to individual patients based on their unique genetic and environmental factors. Furthermore, we discuss telemedicine and remote patient monitoring as methods for improving patient outcomes and reducing healthcare costs. Finally, we examine the growing interest in using artificial intelligence and machine learning in orthopedics, particularly in diagnosis and treatment planning. Overall, these advancements in therapeutic approaches have significantly improved patient outcomes, reduced recovery times, and enhanced the overall quality of care in orthopedic surgery.

Abstract The use of biodegradable polymers for treating bone-related diseases has become a focal point in the field of biomedicine. Recent advancements in material technology have expanded the range of materials suitable for orthopaedic implants. Three-dimensional (3D) printing technology has become prevalent in healthcare, and while organ printing is still in its early stages and faces ethical and technical hurdles, 3D printing is capable of creating 3D structures that are supportive and controllable. The technique has shown promise in fields such as tissue engineering and regenerative medicine, and new innovations in cell and bio-printing and printing materials have expanded its possibilities. In clinical settings, 3D printing of biodegradable metals is mainly used in orthopedics and stomatology. 3D-printed patient-specific osteotomy instruments, orthopedic implants, and dental implants have been approved by the US FDA for clinical use. Metals are often used to provide support for hard tissue and prevent complications. Currently, 70–80% of clinically used implants are made from niobium, tantalum, nitinol, titanium alloys, cobalt-chromium alloys, and stainless steels. However, there has been increasing interest in biodegradable metals such as magnesium, calcium, zinc, and iron, with numerous recent findings. The advantages of 3D printing, such as low manufacturing costs, complex geometry capabilities, and short fabrication periods, have led to widespread adoption in academia and industry. 3D printing of metals with controllable structures represents a cutting-edge technology for developing metallic implants for biomedical applications. This review explores existing biomaterials used in 3D printing-based orthopedics as well as biodegradable metals and their applications in developing metallic medical implants and devices. The challenges and future directions of this technology are also discussed.

AbstractNanotechnology has made significant progress in various fields, including medicine, in recent times. The application of nanotechnology in drug delivery has sparked a lot of research interest, especially due to its potential to revolutionize the field. Researchers have been working on developing nanomaterials with distinctive characteristics that can be utilized in the improvement of drug delivery systems (DDS) for the local, targeted, and sustained release of drugs. This approach has shown great potential in managing diseases more effectively with reduced toxicity. In the medical field of orthopedics, the use of nanotechnology is also being explored, and there is extensive research being conducted to determine its potential benefits in treatment, diagnostics, and research. Specifically, nanophase drug delivery is a promising technique that has demonstrated the capability of delivering medications on a nanoscale for various orthopedic applications. In this article, we will explore current advancements in the area of nanostructured DDS for orthopedic use.

BackgroundNeck pain (NP) is a common musculoskeletal disorder among fighter pilots and has become a rising concern due to its detrimental impact on military combat effectiveness. The occurrence of NP is influenced by a variety of factors, but less attention has been paid to the association of NP with demographic, occupational, and cervical sagittal characteristics in this group. This study aimed to investigate the prevalence and risk factors of NP in Chinese male fighter pilots using a questionnaire and cervical sagittal measurements.MethodsDemographic and flight-related data, as well as musculoskeletal pain information, were gathered from Chinese male fighter pilots via a self-report questionnaire. Cervical sagittal parameters were measured and subtypes were classified using standardized lateral cervical radiographs. Differences in various factors between the case and control groups were analyzed using t-tests or chi-square tests. Binary logistic regressions were conducted to explore potential risk factors contributing to NP. Predictors were presented as crude odds ratios (CORs) and adjusted odds ratios (AORs), along with their respective 95% confidence intervals (CIs).ResultsA total of 185 male fighter pilots were included in this cross-sectional study. Among them, 96 (51.9%) reported experiencing NP within the previous 12 months. The multivariate regression analysis revealed that continuous flight training (AOR: 4.695, 95% CI: 2.226–9.901, p

BackgroundSurgically treated anterior cruciate ligament (ACL) injuries may be a waivable condition and allow return to full flight status, but waivers are based on expert opinion rather than recent published data. The purpose of this study was to evaluate return to flight after anterior cruciate ligament reconstruction (ACLR) in male military aircrews with ACL injuries and to identify factors that affect flight clearance.MethodA single-center retrospective review was conducted by the authors for all active-duty aircrew who underwent ACLR at an authorized military medical center from January 2010 to December 2019. Demographic characteristics, occupational information, surgical data, and flight readiness evaluation outcomes were collected. Based on the final medical evaluation, subjects were divided into a qualified group (N = 64) and a disqualified group (N = 9), and the difference in data collected between the two groups was then analyzed to identify factors affecting flight clearance.ResultsA total of 73 patients underwent successful ACLR with a mean age of 31.6 ± 5.6 years. Non-contact injury was the main type of ACL injury, accounting for 84.9% of the total injuries. 55 cases (75.3%) occurred during daily sports activities and 18 (24.7%) during military training. 64 of the 73 crewmembers (87.7%) were able to return to flight at their last follow-up evaluation. The preoperative interval time (PIT) was significantly less in the qualified group than in the disqualified group (P = 0.002). Patients who underwent ACLR within three months were more likely to return to flying than those who underwent the procedure three months later (97.4% vs. 76.5%, P = 0.010). The incidence of failure to return to flight duty was significantly higher in aircrews with ACL injuries combined with meniscal injuries than in aircrews with isolated ACL injuries (21.4% vs. 0.0%, P = 0.017).ConclusionACLR appears to be safe for military aircrew suffering ACL injuries with or without meniscal injury, and return to flight status is the most likely outcome for the majority of postoperative pilots. Prolonged PIT, PIT > 3 months, and ACL injury combined with meniscus injury had a negative impact on postoperative flight readiness.

The objective of bioimplant engineering is to develop biologically compatible materials for restoring, preserving, or altering damaged tissues and/or organ functions. The variety of substances used for orthopedic implant applications has been substantially influenced by modern material technology. Therefore, nanomaterials can mimic the surface properties of normal tissues, including surface chemistry, topography, energy, and wettability. Moreover, the new characteristics of nanomaterials promote their application in sustaining the progression of many tissues. The current review establishes a basis for nanotechnology-driven biomaterials by demonstrating the fundamental design problems that influence the success or failure of an orthopedic graft, cell adhesion, proliferation, antimicrobial/antibacterial activity, and differentiation. In this context, extensive research has been conducted on the nano-functionalization of biomaterial surfaces to enhance cell adhesion, differentiation, propagation, and implant population with potent antimicrobial activity. The possible nanomaterials applications (in terms of a functional nanocoating or a nanostructured surface) may resolve a variety of issues (such as bacterial adhesion and corrosion) associated with conventional metallic or non-metallic grafts, primarily for optimizing implant procedures. Future developments in orthopedic biomaterials, such as smart biomaterials, porous structures, and 3D implants, show promise for achieving the necessary characteristics and shape of a stimuli-responsive implant. Ultimately, the major barriers to the commercialization of nanotechnology-derived biomaterials are addressed to help overcome the limitations of current orthopedic biomaterials in terms of critical fundamental factors including cost of therapy, quality, pain relief, and implant life. Despite the recent success of nanotechnology, there are significant hurdles that must be overcome before nanomedicine may be applied to orthopedics. The objective of this review was to provide a thorough examination of recent advancements, their commercialization prospects, as well as the challenges and potential perspectives associated with them. This review aims to assist healthcare providers and researchers in extracting relevant data to develop translational research within the field. In addition, it will assist the readers in comprehending the scope and gaps of nanomedicine’s applicability in the orthopedics field.

Nanotechnology has changed science in the last three decades. Recent applications of nanotechnology in the disciplines of medicine and biology have enhanced medical diagnostics, manufacturing, and drug delivery. The latest studies have demonstrated this modern technology’s potential for developing novel methods of disease detection and treatment, particularly in orthopedics. According to recent developments in bone tissue engineering, implantable substances, diagnostics and treatment, and surface adhesives, nanomedicine has revolutionized orthopedics. Numerous nanomaterials with distinctive chemical, physical, and biological properties have been engineered to generate innovative medication delivery methods for the local, sustained, and targeted delivery of drugs with enhanced therapeutic efficacy and minimal or no toxicity, indicating a very promising strategy for effectively controlling illnesses. Extensive study has been carried out on the applications of nanotechnology, particularly in orthopedics. Nanotechnology can revolutionize orthopedics cure, diagnosis, and research. Drug delivery precision employing nanotechnology using gold and liposome nanoparticles has shown especially encouraging results. Moreover, the delivery of drugs and biologics for osteosarcoma is actively investigated. Different kind of biosensors and nanoparticles has been used in the diagnosis of bone disorders, for example, renal osteodystrophy, Paget’s disease, and osteoporosis. The major hurdles to the commercialization of nanotechnology-based composite are eventually examined, thus helping in eliminating the limits in connection to some pre-existing biomaterials for orthopedics, important variables like implant life, quality, cure cost, and pain and relief from pain. The potential for nanotechnology in orthopedics is tremendous, and most of it looks to remain unexplored, but not without challenges. This review aims to highlight the up tp date developments in nanotechnology for boosting the treatment modalities for orthopedic ailments. Moreover, we also highlighted unmet requirements and present barriers to the practical adoption of biomimetic nanotechnology-based orthopedic treatments.

An emerging application of nanotechnology in medicine currently being developed involves employing nanoparticles to deliver drugs, heat, light, or other substances to specific types of cells (such as cancer cells). As most biological molecules exist and function at the nanoscale, engineering and manipulating matter at the molecular level has many advantages in the field of medicine (nanomedicine). Although encouraging, it remains unclear how much of this will ultimately result in improved patient care. In surgical specialties, clinically relevant nanotechnology applications include the creation of surgical instruments, suture materials, imaging, targeted drug therapy, visualization methods, and wound healing techniques. Burn lesion and scar management is an essential nanotechnology application. Prevention, diagnosis, and treatment of numerous orthopedic conditions are crucial technological aspects for patients’ functional recovery. Orthopedic surgery is a specialty that deals with the diagnosis and treatment of musculoskeletal disorders. In recent years, the field of orthopedics has been revolutionized by the advent of nanotechnology. Using biomaterials comprised of nanoparticles and structures, it is possible to substantially enhance the efficacy of such interactions through nanoscale material modifications. This serves as the foundation for the majority of orthopedic nanotechnology applications. In orthopedic surgery, nanotechnology has been applied to improve surgical outcomes, enhance bone healing, and reduce complications associated with orthopedic procedures. This mini-review summarizes the present state of nanotechnology in orthopedic surgery, including its applications as well as possible future directions.

The cold wake caused by a tropical cyclone (TC) extends for hundreds of kilometers and persists for several weeks, thus influencing the surface response for any subsequent TCs that might pass over it. It is commonly accepted that sea-surface temperature (SST) cooling, as produced by a single TC, occurs primarily through vertical mixing. However, when there are sequential TCs, the earlier TC can dramatically change the thermal structure of the upper ocean, which may influence the subsequent development of a latter-occurring TC (LTC). Therefore, the contribution of horizontal advection and vertical mixing to SST-cooling during the passage of LTCs is of great interest. Using a 19-year-long observational dataset and the heat budget analysis of an idealized numerical simulation, the SST change during the passage of sequential TCs is investigated. The results demonstrate that, on average, the SST cooling caused by the LTC shows an overall decreasing trend with enhanced lingering wakes. Budget analysis of the model simulations suggests that an earlier TC can suppress the vertical mixing induced by an LTC mainly through an alteration of dynamics within the deepened mixed layer and that the contribution of vertical mixing to the SST cooling is weaker due to the intensification of the earlier TC. The weakened vertical mixing dominates the decreased SST cooling induced by an LTC. In contrast, the cold wake generated by an earlier TC can produce more cold water on the right side of the TC’s track, which contributes to stronger horizontal advection upon the arrival of the LTC. In general, the effects of the earlier TC can suppress the sea-surface thermal response to an LTC. If the contribution of the horizontal advection to SST cooling is neglected, the SST cooling induced by an LTC could be reduced by about 40%. As for the response of the sub-surface water to the passage of an LTC, the weakened warm anomaly induced by vertical mixing and the enhanced cooling anomaly caused by the vertical advection explain the reduced tendency for the mixed layer to deepen. As a result, the tendency for the mixed layer depth (MLD) to increase is suppressed during the passage of an LTC. These results highlight the importance of optimally depicting cold wakes in numerical simulations to improve the prediction of the upper ocean’s response to sequential TCs.

Procyanidin (PC) is a polyphenolic compound with antioxidant activity. The purpose of this study was to determine the influence of PC on canine sperm quality after 72 h of storage at 4 °C. The collected ejaculates were separated into four equal aliquots and treated with various concentrations of PC (0, 10, 30, and 50 μg/mL) in Tris-citric-fructose-egg yolk (TCFE) extender and stored at 4 °C for 72 h. The findings revealed that 30 μg/mL PC was the optimum concentration for significantly improving sperm motility (p < 0.05). Sperm samples treated with 30 μg/mL PC had substantially greater plasma membrane integrity, acrosome integrity, and mitochondrial membrane potential than the control group (p < 0.05). Furthermore, T-AOC and the expression levels of superoxide dismutase 1 (SOD1), catalase (CAT), and glutathione peroxidase 1 (GPx1) genes were significantly higher in sperm treated with 30 μg/mL PC than those in control (p < 0.05). In summary, this study discovered that adding PC to the TCFE extender enhanced sperm quality and that 30 μg/mL PC was the optimal concentration for canine sperm when stored at 4 °C.

The control of nonlinear dynamics is gaining increasing attention since many practical systems are with such kind of characteristics. To deal with the system uncertainty, in this paper, the efficient learning control using neural network is proposed for the nonlinear strict-feedback system. The whole scheme is with the back-stepping design, while the novel learning is proposed for the neural network weights update. To deal with the approximation error, the robust item is added. The stability of the closed-loop dynamics is analysed and the effectiveness of the design is verified through flight simulation.

Abstract To explore the effects of air‐sea interaction on the eyewall replacement cycle (ERC) of tropical cyclones (TCs), an ERC of Typhoon Sinlaku (2008) was reproduced using the high‐resolution coupled ocean‐atmosphere‐wave‐sediment transport (COAWST) model. The numerical simulations were evaluated with a wide range of observational datasets. Moreover, the importance of the ocean to ERC is discussed by comparing six sensitive experiments, that is, three uncoupled experiments with different time‐invariant sea surface temperatures, an ocean‐atmosphere coupled experiment, an ocean‐wave coupled experiment, and an ocean‐atmosphere‐wave fully coupled experiment. The results show that Sinlaku simulated by the fully coupled experiment was highly consistent with the observations, and the evolution of ERC varies from those only simulated by the atmospheric models in previous studies. When the ocean and waves were both considered, the lifetime of the ERC was significantly prolonged, even though the simulated Sinlaku was weakened by the cooling of the sea; the asymmetric distribution of the concentric eyewalls (CEs) which caused by the non‐uniform energy exchanges was also prominent. By contrast, without ocean coupling, the simulated secondary eyewall, composed of axisymmetric convections, exhibited false enhancement and fake inward contraction, and the duration of the ERC was also shorter than that actually observed. In conclusion, the results highlight the significance of ocean coupling for the numerical simulation of the ERC of a TC, including survival time and asymmetric structure.

In this paper, a new prediction approach is proposed for ocean vessel heave compensation based on echo state network (ESN). To improve the prediction accuracy and enhance the robustness against noise and outliers, a generalized similarity measure called correntropy is introduced into ESN training, which is referred as corr-ESN. An iterative method based on half-quadratic minimization is derived to train corr-ESN. The proposed corr-ESN is used for the heave motion prediction. The experimental results verify its effectiveness.

Dust particles in the atmosphere play an important role in air pollution, climate change, and biogeochemical cycles. Some of the dominant sources of dust in mid-latitude regions are in Asia. An intense dust storm engulfed Northern China at the beginning of May 2017, and PM10 mass concentrations of 1500–2000 μg m−3 were measured near the dust source region. We combined numerical simulations, air quality monitoring data, and satellite retrievals to investigate dust emission and transport during this event. We found that the event was closely related to cold front activity, characterized by increased wind speed, which increased dust emission. We improved the dust scheme using a local dust size distribution to better simulate the dust emission flux. We found that accurate parametrization of the dust size distribution was important to effectively simulate both dust emission and ambient particle concentration. We showed that using a local dust size distribution substantially improved the accuracy of the simulation, allowing both the spatial distribution of pollution caused by the dust storm and temporal variability in the pollution to be captured.

This study explored the influence of choosing a nonhydrostatic dynamical core or a hydrostatic dynamical core in the weather research and forecasting (WRF) model on the intensity and structure of simulated tropical cyclones (TCs). A comparison of cloud-resolving simulations using each core revealed significant differences in the TC simulations. In comparison with the nonhydrostatic simulation, the hydrostatic simulation produced a stronger and larger TC, associated with stronger convective activity. A budget analysis of the vertical momentum equation was conducted to investigate the underlying mechanisms. Although the hydrostatic dynamical core was used, the vertical motion was not in strict hydrostatic balance because of the existence of the vertical perturbation pressure gradient force, local buoyancy force, water loading, and sum of the Coriolis and diffusion effects. The contribution of the enhanced vertical perturbation pressure gradient force was found to be more important for stronger upward acceleration in the eyewall in the hydrostatic simulation than in the nonhydrostatic simulation. This is because it leads to intensified convection in the eyewall that releases more latent heat, which induces a larger low-level radial pressure gradient and inflow motion, and eventually leads to a stronger storm.

This paper presents a new combined method for the short-term load forecasting of electric power systems based on the Fuzzy c-means (FCM) clustering, particle swarm optimization (PSO) and support vector regression (SVR) techniques. The training samples used in this method are of the same data type as the learning samples in the forecasting process and selected by a fuzzy clustering technique according to the degree of similarity of the input samples considering the periodic characteristics of the load. PSO is applied to optimize the model parameters. The complicated nonlinear relationships between the factors influencing the load and the load forecasting can be regressed using the SVR. The practical load data from a city in Chongqing was used to illustrate the proposed method, and the results indicate that the proposed method can obtain higher accuracy compared with the traditional method, and is effective for forecasting the short-term load of power systems.