Search Results (363)

Ion beam figuring (IBF) is an ultra-high-precision surface finishing technology characterized by a distinct trade-off between the spot size of the removal function and its corresponding figuring capabilities. A larger spot size for the removal function leads to higher processing efficiency but lower figuring ability. Conversely, a smaller spot size results in higher figuring ability but lower efficiency. Adjusting the spot size of the removal function using tools with an aperture is a possible approach. However, existing variable-aperture tools have certain limitations in IBF processing. To leverage the advantages of both large and small spot sizes for the removal function during IBF processing, an in situ dynamic beam variable-aperture device has been designed. This device optimizes the parameters of diaphragm sheets and employs FOC for dynamic aperture adjustment. Simulations show that 12 numbers of 0.1 mm-thick sheets minimize removal function distortion, with the thermal strain-induced area variation being <5%. FOC enables rapid (≤0.45 s full range) and precise aperture control. Experiments confirm adjustable spot sizes (FWHM 0.7–17.2 mm) with Gaussian distribution (correlation >96.7%), operational parameter stability (relative change rate ≤5%), and high repeatable positioning precision (relative change rate ≤3.2% in repeated adjustments). The design enhances IBF efficiency, flexibility, and accuracy by enabling in situ spot size optimization, overcoming conventional limitations. Full article

Introduction: Efficient communication and collaboration among local health departments (LHDs), healthcare organizations, governmental entities, and other community stakeholders are critical for public health preparedness and response. This study evaluates (1) the impact of informatics on LHDs’ frequency and collaboration in creating consistent COVID-19 messaging; (2) the influence of informatics on targeted messaging for vulnerable populations; and (3) LHD characteristics linked to their consistent and/or targeted messaging engagement. Methods: This study analyzed the 2020 National Association of County and City Health Officials (NACCHO) Forces of Change (FOC) survey, the COVID-19 Edition. Of the 2390 LHDs invited to complete the core questionnaire, 905 were asked to fill out the module questionnaire as well. The response rate for the core was 24% with 587 responses, while the module received 237 responses, achieving a 26% response rate. Descriptive analyses and six logistic regression models were utilized. Results: Over 80% (183) of LHDs collaborated regularly with public health partners, and 95% (222) used information management applications for COVID-19. Most interacted with local and state agencies, but only half with federal ones. LHDs that exchanged data with local non-health agencies, engaged with local non-health agencies, and communicated weekly to daily with the public about long-term/assisted care had higher odds of creating consistent messages for the public, and about the use and reuse of masks had lower odds of collaborating with public health partners to develop consistent messages for the public. Conclusion: Our findings underscore the centrality of informatics infrastructure and collaboration in ensuring equitable public health messaging. Strengthening public health agencies and investing in targeted training are crucial for effective communication across the communities served by these agencies. Full article

Background/Objectives: Hallucinogenic substances such as psilocybin, psilocin, ergometrine, ergotamine, and lysergic acid diethylamide (LSD) have been demonstrated to enhance the force of contraction (FOC), in part due to the phosphorylation of phospholamban in human atrial preparations via 5-HT₄ serotonin receptors and/or H₂ histamine receptors. However, whether psilocybin or psilocin acts at isolated mammalian ventricular preparations and whether they increase protein phosphorylation in the mammalian ventricle remains to be elucidated. Methods: To this end, the FOC and phospholamban phosphorylation in isolated perfused hearts from transgenic mice with cardiomyocyte-specific overexpression of either human 5-HT₄ receptors (5-HT₄-TG) or human H₂ receptors (H₂-TG) and their wild-type littermates (WT) were examined. Furthermore, the ergot alkaloids ergometrine, ergotamine, and LSD were used as references. Results: Psilocybin and psilocin enhanced the FOC to 137% and to 152%, respectively, and elevated the phospholamban phosphorylation in isolated perfused hearts from 5-HT₄-TG. In H₂-TG hearts, psilocybin and psilocin increased the FOC to a much lesser extent but had no effect on the phospholamban phosphorylation. In contrast, LSD increased the FOC and phosphorylation state of phospholamban in isolated hearts of both 5-HT₄-TG and H₂-TG. On the other hand, ergometrine and ergotamine increased the FOC only in H₂-TG. Ergometrine increased the phosphorylation state of phospholamban in perfused hearts from H₂-TG, but not from 5-HT₄-TG. Ergotamine failed to increase the phospholamban phosphorylation in both H₂-TG and 5-HT₄-TG. Psilocybin, psilocin, ergotamine, ergometrine, and LSD were unable to increase FOC and phospholamban phosphorylation in perfused hearts from WT. Conclusions: The increase in the phosphorylation state of phospholamban could provide a partial explanation for the positive inotropic effects and the relaxant effects of not only psilocybin and psilocin but also ergometrine and LSD in the isolated hearts of the animals used in this study. Full article

Chickpea is a legume that grows in most parts of the world. It is negatively affected by abiotic and biotic factors like drought and fungal diseases, respectively. One of the most important soil-borne pathogens affecting chickpeas is Fusarium oxysporum f.sp. ciceris (Foc). Its population dynamics in the soil are affected by fluctuations in soil water content and host characteristics. For the last three decades, drought has been common in most areas of the world due to global warming. Drought stress decreases the quality and quantity of the chickpeas, particularly where soil-borne pathogens are the main stress factor for plants. The use of both drought-tolerant and disease-resistant cultivars may be the only option for cost-effective yield production. In this study, we screened the seeds of twelve chickpea genotypes WR-315, JG-62, C-104, JG-74, CPS-1, BG-212, ANNIGERI, CHAFFA, BG-215, UC-27, ILC-82, and K-850 for drought tolerance at increasing polyethylene glycol (PEG) concentrations (0-, 5-, 7.5-, 10-, 15-, 20-, 25-, 30- and 50%) to create drought stress conditions at different severities. The performances of genotypes that were previously tested in Foc resistance/susceptibility studies were assessed in terms of percentage of germination, radicle and hypocotyl length, germination energy, germination rate index, mean germination time, and vigor index in drought conditions. We determined the genotypes of C-104, CPS-1, and WR-315 as drought-susceptible, moderately drought-tolerant, and drought-tolerant, respectively. We then elucidated the stress levels of selected genotypes (20-day-old seedlings) at 0–15% PEG conditions via measuring proline and malondialdehyde (MDA) contents. Our findings showed that genotypes that were resistant to Foc also exhibited drought tolerance. The responses of chickpea genotypes infected with Foc under drought conditions are the next step to assess the combined stress on chickpea genotypes. Full article

Background: Fear of childbirth (FOC) or tokophobia has a detrimental impact on women during and after pregnancy. Childbirth fear is multidimensional and may differ across nations and cultures. We aimed to determine the psychosocial determinants of tokophobia among Asians. Methods: We conducted a systematic literature search using the PubMed, Scopus, and Web of Science databases in September 2023. Included were original English-language articles that focused on Asian cohorts. We identified independent variables associated with maternal childbirth fear based on multivariable logistic and linear regression analysis. Results: Twenty-three studies are discussed in this review. We categorized the factors into (1) psychiatry, (2) psychology, (3) perception and experience, (4) relationships and support, (5) spirituality, and (6) COVID-19. The studies involved 10,538 women with overall FOC prevalence ranging between 56.6% to 82.1%. Maternal history of psychiatric disorder, depression, and anxiety were positive predictors of childbirth fear. Childbirth self-efficacy protects Asian mothers against tokophobia. A reduced level of fear was associated with higher maternal psychological and spiritual well-being, as well as stronger maternal resilience. Spousal and social support alongside good family function were shown to exert a protective effect against childbirth fear. Intimate partner abuse was associated with an increased risk of tokophobia in women. Studies during the pandemic indicated that maternal fear, obsession, and anxiety about COVID-19 were positively correlated to fear of childbirth. Conclusions: Childbirth fear among Asian women is greatly influenced by various psycho-social factors. More culturally driven research is needed to help develop relevant interventions that will enhance maternal psychological and spiritual well-being and reduce the fear of childbirth. Full article

This paper proposes a super-twisting sliding-mode control (STSMC) strategy to enhance the efficiency and stability of a heaving point absorber wave energy converter (PAWEC) system equipped with a permanent magnet synchronous generator (PMSG). In particular, the STSMC is designed to address both generator-side and grid-side control challenges by ensuring precise regulation under varying wave conditions. A dynamical model of the PAWEC is developed to describe system responses, while the power take-off (PTO) mechanism is tailored to maintain consistent generator speed and efficient energy conversion. Lyapunov stability theory is employed to verify the stability of the proposed controller. Simulation studies and tests on a small-scale experimental setup with a 500 W PAWEC model under regular and irregular waves demonstrate that STSMC improves generator speed regulation and power output by more than 30% compared to field-oriented control (FOC), nonlinear adaptive backstepping (NAB), and first-order sliding-mode control (FOSMC). The proposed approach also manages grid-side total harmonic distortion (THD) effectively, keeping it below 5%. These results indicate that STSMC can substantially improve the dynamic performance and energy efficiency of wave energy systems. Full article

In reactive power compensators applied in drives with asynchronous motors, a control strategy focusing on the compensation of higher-order current harmonics is implemented. Control schemes of such compensators typically employ low-pass Butterworth filters with fixed cut-off frequencies to isolate the reactive power component. However, the impact of alternative filter types on compensator performance remains insufficiently explored. Furthermore, in the control systems under consideration, stator phase current signals of the asynchronous motor are used as reference inputs. This approach proves effective under the steady-state operating conditions of the drive. Under non-steady-state operating conditions—typical for traction drive systems—this approach becomes ineffective due to the increased complexity in obtaining accurate reference current signals. As a result, the performance of the filters also deteriorates. It is therefore proposed to investigate the impact of alternative filter types on the efficiency of compensator operation. To address this challenge, the following strategies are suggested: implement higher-order harmonic compensation in the system of stator phase supply voltages of the asynchronous motor; use the control signals from the Field-Oriented Control (FOC) algorithm as reference inputs; and adapt the cut-off frequencies of the filters dynamically to match the frequency of the supply voltage. The simulation results indicate that the use of an elliptic filter in compensator control systems yielded the highest effectiveness. Moreover, the results confirmed the efficiency of the proposed solutions under both steady-state and non-steady-state operating conditions of the traction drive. These approaches support the development of reactive power compensators integrated into traction drive systems for railway rolling stock. Full article

This paper introduces a novel field-oriented control (FOC) strategy for an open-end stator three-phase winding induction motor (OEW-TP-IM) using dual space vector modulation-pulse width modulation (SVM-PWM) inverters. This configuration reduces common mode voltage at the motor’s terminals, enhancing efficiency and reliability. The study presents a backstepping control approach combined with a mean value theorem (MVT)-based observer to improve control accuracy and stability. Stability analysis of the backstepping controller for key control loops, including flux, speed, and currents, is conducted, achieving asymptotic stability as confirmed through Lyapunov’s methods. An advanced observer using sector nonlinearity (SNL) and time-varying parameters from convex theory is developed to manage state observer error dynamics effectively. Stability conditions, defined as linear matrix inequalities (LMIs), are solved using MATLAB R2016b to optimize the observer’s estimator gains. This approach simplifies system complexity by measuring only two line currents, enhancing responsiveness. Comprehensive simulations validate the system’s performance under various conditions, confirming its robustness and effectiveness. This strategy improves the operational dynamics of OEW-TP-IM machine and offers potential for broad industrial applications requiring precise and reliable motor control. Full article

This review examines the application of the geophysical methods for Transportation Infrastructure Slope Monitoring (TISM). In contrast to existing works, which address geophysical methods for natural landslide monitoring, this study focuses on their application to infrastructure assets. It addresses the key aspects regarding the geophysical methods most employed, the subsurface properties revealed, and the design of monitoring systems, including sensor deployment. It evaluates the benefits and challenges associated with each geophysical approach, explores the potential for integrating geophysical techniques with other methods, and identifies the emerging technologies. Geophysical techniques such as Electrical Resistivity Tomography (ERT), Multichannel Analysis of Surface Waves (MASW), and Fiber Optic Cable (FOC) have proven effective in monitoring slope stability and detecting subsurface features, including soil moisture dynamics, slip surfaces, and material heterogeneity. Both temporary and permanent monitoring setups have been used, with increasing interest in real-time monitoring solutions. The integration of advanced technologies like Distributed Acoustic Sensing (DAS), UAV-mounted sensors, and artificial intelligence (AI) promises to enhance the resolution, accessibility, and predictive capabilities of slope monitoring systems. The review concludes with recommendations for future research, emphasizing the need for integrated monitoring frameworks that combine geophysical data with real-time analysis to improve the safety and efficiency of transportation infrastructure management. Full article

Fusarium oxysporum f. sp. cubense (Foc) causes Fusarium wilt, a devastating epidemic disease that has caused widespread damage to banana crops worldwide. We report the draft genomes of Foc race 1 (16117) and Foc tropical race 4 (Fusarium odoratissimum) (CNSD1) isolates from China, assembled using PacBio HiFi sequencing reads, with functional annotation performed. The strains group in distinct lineages within the Fusarium oxysporum species complex. This genetic resource will contribute towards understanding the pathogenicity and evolutionary dynamics of Foc populations in banana-growing regions around the world. Full article

Various sectors focus on transitioning to clean and renewable energy sources, particularly airport microgrids (AMGs), which offer the potential for highly reliable and resilient operations. As airports increasingly integrate renewable energy sources, ensuring stable and efficient power becomes a critical challenge. In this context, maintaining proper frequency is essential for the reliable operation of AMGs, which helps maintain grid stability and reliable operation. This paper proposes a new hybrid disturbance observer-based controller with a fractional-order controller (DOBC/FOC) for operating AMGs with high levels of renewable energy integration and advanced frequency regulation (FR) capabilities. The proposed controller utilizes DOBC coupled with a non-integer FOC for load frequency control (LFC), optimized for peak performance under varying operational conditions. In addition, a decentralized control strategy is introduced to manage the participation of electric vehicles and lithium-ion battery systems within the airport’s energy ecosystem, enabling effective demand response and energy storage utilization. Furthermore, the parameters of these controllers are optimized simultaneously to ensure optimal performance in both transient and steady-state conditions. The proposed DOBC/FOC controller demonstrates strong performance and reliability according to simulation outcomes, showcasing its superior performance in maintaining frequency stability, reducing fluctuations, and ensuring continuous power supply in diverse operating scenarios, such as 55.5% and 76.5% in step load perturbations when compared to the utilization of electric vehicles (EVs) and electric aircraft (EAC), respectively. These results underline the potential of this approach in enhancing the resilience and sustainability of AMG and contributing to more intelligent and eco-friendly airport infrastructure. Full article

This paper proposes a sensorless field-oriented control (FOC) strategy for permanent magnet synchronous motors (PMSMs), focusing on rotor flux position estimation based on back-electromotive force (back-EMF) signals. The limitations of conventional phase-locked loop (PLL) techniques for rotor flux position estimation along the motor shaft are analyzed, and an enhanced PLL structure is developed to address these deficiencies.In electric vehicle traction applications, precise flux position estimation alone is insufficient; accurate generation of d–q-axis current commands is equally critical. To address this need, a zero-pole-free PI regulator is designed within the PLL module, enabling more accurate flux estimation. Additionally, a gradient-based self-tuning algorithm is employed to identify system parameters, particularly the stator inductance, enabling the controller to optimize current command generation.Comprehensive system-level simulations have been conducted to validate the effectiveness of the proposed sensorless control scheme. Comparative studies demonstrate that the proposed method significantly improves feasibility and robustness for practical PMSM drive applications. Full article

Banana wilt disease is an important disease in banana production, causing significant losses. Herein, we investigated the mechanism by which Bacillus velezensis isolate X5 enhances the resistance of different resistant banana cultivars to Fusarium oxysporum f. sp. cubense race 4 (Foc4). From the perspectives of metabolism, transcriptome, and key genes in important pathways, this study analyzed the composition and content changes of other types of signaling molecules, such as free amino acids and soluble sugars, in resistant/susceptible varieties. The results indicate that under pathogen stress, the contents of root-secreted metabolite components in both resistant and susceptible varieties increase significantly overall, and the increase in susceptible varieties is generally higher. For example, the free amino acid components in susceptible varieties are significantly more than those in resistant varieties. However, the addition of biocontrol bacteria can inhibit this increase. Exogenous addition experiments prove that differential metabolites can either promote or inhibit Foc4 and X5 at certain concentrations. The results of KEGG (Kyoto Encyclopedia of Genes and Genomes) enrichment and GO (Gene Ontology) annotation show that resistant varieties have more defense pathways compared to susceptible varieties. Under X5 treatment, more defense genes in resistant varieties are activated or their expression is enhanced, promoting the plant roots to secrete more substances related to plant resistance, such as phenylpropanoids and lignin. This research revealed the effects of Bacillus velezensis on bananas and pathogens, allowing valuable conclusions to be drawn. The results have good application potential to understand the relationships among the three species, defining the biocontrol effect and mechanism of Bacillus velezensis, and providing a theoretical basis for the biological control of soil-borne diseases such as banana wilt disease. Full article

The integration of renewable energy sources, such as wind power, into the electrical grid is essential for the development of sustainable energy systems. Doubly fed induction generators (DFIGs) have been significantly utilized in wind energy conversion systems (WECSs) because of their efficient power generation and variable speed operation. However, optimizing wind power extraction at variable wind speeds remains a major challenge. To address this, an artificial neural network (ANN) is adopted to predict the optimal shaft speed, ensuring maximum power point tracking (MPPT) for a wind energy-driven DFIG connected to a matrix converter (MC). The DFIG is controlled via field-oriented control (FOC), which allows independent power output regulation and separately controls the stator active and reactive power components. Through its compact design, bidirectional power flow, and enhanced harmonic performance, the MC, which is controlled by the simplified Venturini modulation technique, improves the efficiency and dependability of the system. Simulation outcomes confirm that the ANN-based MPPT enhances the power extraction efficiency and improves the system performance. This study shows how wind energy systems can be optimized for smart grids by integrating advanced control techniques like FOC and simplified Venturini modulation with intelligent algorithms like ANN. Full article

Plant defensin (PDF/DEF), an important pathogenesis-related protein which widely exists in plants, displays broad-spectrum antifungal activities. To date, however, reports on the banana PDFs are very limited. In this study, we identified, cloned, and characterized the five Class I PDFs (MaPDF2.1~MaPDF2.5) in banana (Musa acuminata). Further, their expression in root, corm, leaf, and fruit were studied. MaPDFs exhibited quite different expression patterns in different organs, with MaPDF2.2 as the only member expressing in all the tested organs, and its expression levels in all organs were the highest among all MaPDFs. The MaPDF2.2 expression could be significantly upregulated by both low- and high-temperature stresses but significantly downregulated by the inoculations of plant growth promoting endophytic fungus Serendipita indica and banana Fusarium wilt (FW) pathogen Fusarium oxysporum f. sp. cubense (Foc) Tropical race 4 (FocTR4). Moreover, the S. indica pre-colonization could significantly alleviate the suppression of FocTR4 on MaPDF2.2, suggesting that this MaPDF might contribute greatly to the S. indica-enhanced FW resistance. By using tobacco leaf transient overexpression, the function of MaPDF2.2 was investigated. Its overexpression significantly inhibited the infection of Foc race 1 (Foc1) and FocTR4 in tobacco leaves. Furthermore, in vitro antifungal ability assays revealed that the recombinant His-MaPDF2.2 protein could significantly inhibit the growth of Foc1 and FocTR4, as well as the pigment accumulation of Foc1. Our study revealed the sequence and expression characteristics of banana PDFs and demonstrated the antifungal ability of MaPDF2.2 to FW pathogens. Full article