Search Results (993)

To enable accurate evaluation of satellite laser communication terminals under solar outage interference, this paper presents the design and implementation of a solar radiation simulation system targeting the 1540–1560 nm communication band. The system reconstructs co-propagating interference conditions through standardized and continuously tunable output, based on high irradiance and spectral uniformity. A compound beam homogenization structure—combining a multimode fiber and an apodizator—achieves 85.8% far-field uniformity over a 200 mm aperture. A power–spectrum co-optimization strategy is introduced for filter design, achieving a spectral matching degree of 78%. The system supports a tunable output from 2.5 to 130 mW with a 50× dynamic range and maintains power control accuracy within ±0.9%. To suppress internal background interference, a BRDF-based optical scattering model is established to trace primary and secondary stray light paths. Simulation results show that by maintaining the surface roughness of key mirrors below 2 nm and incorporating a U-shaped reflective light trap, stray light levels can be reduced to 5.13 × 10⁻¹² W, ensuring stable detection of a 10⁻¹⁰ W signal at a 10:1 signal-to-background ratio. Experimental validation confirms that the system can faithfully reproduce solar outage conditions within a ±3° field of view, achieving consistent performance in spectrum shaping, irradiance uniformity, and background suppression. The proposed platform provides a standardized and practical testbed for ground-based anti-interference assessment of optical communication terminals. Full article

Background: Pancreas and pancreas–kidney transplantation are well-established therapeutic options for patients with type 1 diabetes mellitus (T1DM) and end-stage kidney disease (ESKD), offering the potential to restore endogenous insulin production and kidney function. It improves metabolic control, quality of life, and long-term survival. While surgical techniques and immunosuppressive strategies have advanced considerably, graft rejection and limited long-term graft survival remain significant clinical challenges. Method: To better understand these risks, the genetic and immunological factors that influence transplant outcomes are examined. Beyond traditional human leukocyte antigen (HLA) matching, non-HLA genetic variants such as gene deletions and single-nucleotide polymorphisms (SNPs) have emerged as contributors to alloimmune activation and graft failure. Result: Polymorphisms in cytokine genes, minor histocompatibility antigens, and immune-regulatory pathways have been implicated in transplant outcomes. However, the integration of such genomic data into clinical practice remains limited due to underexplored gene targets, variability in study results, and the lack of large, diverse, and well-characterized patient cohorts. Initiatives like the International Genetics & Translational Research in Transplantation Network (iGeneTRAiN) are addressing these limitations by aggregating genome-wide data from thousands of transplant donors and recipients across multiple centers. These large-scale collaborative efforts aim to identify clinically actionable genetic markers and support the development of personalized immunosuppressive strategies. Conclusions: Overall, genetic testing and genomics hold great promise in advancing precision medicine in pancreas and pancreas–kidney transplantation. Full article

Ultra-high-temperature and pressure downhole environments pose challenges for conventional electronic instruments to adapt to high-temperature formations, thereby restricting the application of downhole electronic tool technology in deep and ultra-deep wells. Given the aforementioned limitation of electronic inclination measurement systems, specifically their poor temperature resistance, this study proposes a novel shunt flow control method. This method employs a mechanical structure to overcome temperature constraints: gravitational torque generated by the mechanical structure is utilized to control valve opening and regulate flow rate. By converting sensed well inclination information into changes in flow rate, this approach enables the transformation of well inclination sensing and its associated signals. In this study, a kinetic analysis model of the shunt-regulating valve spool was established. Using computational fluid dynamics (CFD) simulations, the flow characteristics of the regulating spool were analyzed under varying valve openings. The structure of the flow control valve was optimized with the goal of maximizing internal flow. Finally, the reliability of the designed structure for well deviation sensing and flow control was verified using simulation experimental studies and theoretical analyses. Full article

Background: Perioperative care is an integral part of the procedure of a surgical operation, with strictly defined rules. The need to upgrade and improve some individual long-term processes aims at optimal patient care and the provision of high-level health services. Therefore, preoperative care is drawn up with new data resulting from the evolution of technology to upgrade the procedures that need improvement. According to the international literature, a factor considered to be of major importance is high preoperative anxiety and its effects on the patient’s postoperative course. High preoperative anxiety is postoperatively responsible for prolonged hospital stays, increased postoperative pain, decreased effect of anesthetic agents, increased amounts of analgesics, delayed healing of surgical wounds, and increased risk of infections. The use of Virtual Reality technology appears as a new method of managing preoperative anxiety. Objective: This study investigates the effect and effectiveness of Virtual Reality (VR) technology in managing preoperative anxiety in adult patients. Methods: A literature review was performed on 193 articles, published between 2017 and 2024, sourced from the scientific databases PubMed and Cochrane, as well as the trial registry ClinicalTrials, with a screening and exclusion process to meet the criterion of investigating VR technology’s effectiveness in managing preoperative anxiety in adult patients. This systematic review was conducted under the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA 2020) guidelines. Results: Out of the 193 articles, 29 were selected. All articles examined the efficacy of VR in adult patients (≥18) undergoing various types of surgery. The studies represent a total of 2.354 participants from 15 countries. There are two types of VR applications: distraction therapy and patient education. From the studies, 14 (48%) used the distraction VR intervention, 14 (48%) used the training VR intervention, and 1 (4%) used both VR interventions, using a range of validated anxiety scales such as the STAI, VAS-A, APAIS, and HADS. Among the 29 studies reviewed, 25 (86%) demonstrated statistically significant reductions in preoperative anxiety levels following the implementation of VR interventions. VR technology appears to manage preoperative anxiety effectively. It is a non-invasive and non-pharmacological intervention with minimal side effects. Conclusions: Based on the review, the management of preoperative anxiety with VR technology shows good levels of effectiveness. Further investigation of the efficacy by more studies and randomized controlled trials, with a larger patient population, is recommended to establish and universally apply VR technology in the preoperative care process as an effective method of managing preoperative anxiety. Full article

The Maowusu Desert is still suffering from serious ecological and environmental security issues such as wind erosion and desertification, influenced by both natural and human factors. The amendment of aeolian sandy soil with soft rock material presents an effective erosion control strategy, leveraging the complementary structural and compositional properties of both materials to enhance soil stability and rehabilitate degraded environments. However, there are few studies that investigate the effect of soil surface electrochemical properties and particle interaction forces on the structural stability of compound soils with soft rock and sandy soil. This decade-long field study quantified the electrochemical properties and interparticle forces and their synergistic effects on structural stability across five soft rock-to-aeolian sandy soil blend volume ratios (0:1, 1:5, 1:2, 1:1, 1:0) within the 0–30 cm soil profile. The results showed that the soil organic matter (SOM), specific surface area (SSA), and cation exchange capacity (CEC) significantly increased with the incorporation of soft rock material. For five different proportions, with the addition of soft rock and the extension of planting years, the content of SOM increased from 5.65 g·kg⁻¹ to 11.36 g·kg⁻¹, the CEC varied from 4.68 cmol kg⁻¹ to 17.91 cmol kg⁻¹, while the σ₀ importantly decreased from 1.8 to 0.47 c m⁻² (p < 0.05). For the interaction force at 2.4 nm between soil particles, the absolute value of van der Waals attractive force increased from 0.10 atm to 0.38 atm, and the net force decreased from 0.09 atm to −0.30 atm after the incorporation ratios of soft rock from 0:1 to 1:1. There was a significant negative correlation between the resultant net force between the particles of compound soil and the SSA and CEC. These results indicate that the addition of soft rock material positively improves the surface electrochemical properties and internal forces between aeolian sandy soil particles, further enhancing its structural stability. This study establishes a foundational theoretical framework for advancing our mechanistic understanding of aeolian sand stabilization and ecosystem rehabilitation in the Mu Us Desert. Full article

Introduction: Overactive bladder (OAB) and urinary incontinence (UI) are prevalent, particularly in older adults, and affect quality of life. OAB involves urgency, frequency, nocturia, and urgency incontinence, often linked to involuntary detrusor contractions. Treatment guidelines recommend a stepwise approach, starting with pelvic floor muscle training (PFMT), followed by pharmacological or minimally invasive therapies, such as neuromodulation. However, the combined effects of PFMT and neuromodulation have not been well established. This study aimed to evaluate the impact of combining pelvic floor exercises with neuromodulation versus PFMT with sham neuromodulation or standard physiotherapy after a 12-week intervention in individuals with OAB and UI. Methods/Materials: A double-blind, randomized controlled trial was designed with three groups: PFMT + neuromodulation, PFMT + sham, and conventional physiotherapy (control) in a 1:1:1 ratio. This study followed the CONSORT guidelines and was registered at ClinicalTrials.gov (NCT06783374). The sample size was calculated using GPower^® software, assuming a Cohen’s effect size of 1.04, a power of 0.80, an alpha of 0.05, and a 15% dropout rate, totaling 63 participants (21 per group). Participants attended 24 sessions over 12 weeks (2 sessions per week). The interventions were based on previously validated protocols. Outcomes: The primary outcomes included health-related quality of life, pelvic floor muscle function, pain, adherence, and general health. The secondary outcomes included Incontinence Quality of Life questionnaire, 3-day bladder diary, International Consultation on Incontinence Questionnaire–Urinary Incontinence Short Form, kinesiophobia, and electromyographic data. Full article

Background: Computed Tomography (CT) imaging is widely recognised for its high capability in assessing multiple organs. However, concerns about patient radiation exposure, particularly in children, pose significant challenges. Objective: This study aimed to establish diagnostic reference levels (DRLs) for paediatric patients in the most common CT examinations to monitor and better control radiation doses. Methods: Dosimetry records from 5956 patients’ scans for the four most common CT imaging examinations—Head, Chest, Abdomen Pelvis (AP), and Chest Abdomen Pelvis (CAP)—were considered. The CT dosimetric quantities (CT dose-index volume (CTDI_vol) and dose-length product (DLP)), along with patient demographics (age and weight), were collected from radiology data storage systems. DRLs for CTDI_vol and DLP were determined for each imaging examination, stratified by patient age and weight groups, in accordance with ICRP recommendations. Results: The derived DRLs are presented as [median CTDI_vol (mGy): median DLP (mGy·cm)]. For (<1 yr): Head: 13:187, Chest: 0.4:7, AP: 0.9:19, CAP: 0.4:10. For (1–5 yrs): Head: 16:276, Chest: 1:22, AP: 1.5:58, CAP: 1.6:63. For (6–10 yrs): Head: 19:332, Chest: 1.4:35, AP: 1.9:74, CAP: 2:121. For (11–15 yrs): Head: 21:391, Chest: 3:86, AP: 4.1:191, CAP: 3:165. We observed that both the CTDI_vol and DLP DRL values increase with patient age. Weight-based DRLs follow similar trends for CTDI_vol, while DLP values show noticeable variations in Chest and AP examinations. Conclusions: The study findings highlight the need for review and optimisation of certain scanning protocols, particularly for chest and AP examinations. The derived DRLs are consistent with findings from other studies. The study recommends establishing national paediatric DRLs to enhance radiology practice across the country and ensure adherence to international safety standards. Full article

The cognitive cycle has been studied via cognitive architectures and by analyzing cognitive experiments. An emerging theoretical approach suggests that several automatic cognitive processes retrieve information, making it available to an internal agent, which in turn decides which information to access. Derived from this view, four phases of the cognitive cycle can be formulated and reproduced within a cognitive monitoring system. This exploratory work presents a new theory, Attention as Internal Action, and proposes a hypothesis about the relationship between an iteration of the cognitive cycle and a conscious motor action. The design of a continuous reaction time task is presented as a tool for quick cognitive evaluation. Via continuously provided user responses, the computational system behind the task adapts triggering stimuli based on the suggested hypothesis. Its software implementation was employed to assess whether a previously conducted simulation of the cognitive cycle’s time range aligned with empirical data. A control group was assigned to perform a separate simple reaction time task in a sequence of five days. The analysis showed that the experimental cognitive monitoring system produced results more closely aligned with the established understanding of the timing of the cognitive cycle than the control task did. Full article

The Engine Electronic Controller (EEC), as the core component of an aircraft engine control system, is vulnerable to rapid failure when exposed to thermal shock during engine fire incidents, potentially leading to catastrophic aviation accidents. To address this issue, this study conducts both numerical simulations and experimental investigations to evaluate the thermal performance of the EEC under thermal shock conditions, exploring the weaknesses of the EEC chassis under high-temperature thermal shock and the damage to important internal electronic components. A three-dimensional finite element model of the EEC was established to simulate its behavior under a thermal shock of 1100 °C. Simulation results reveal that the aluminum alloy chassis wall cannot withstand the extreme thermal load, resulting in failure of the internal electronic components within the first 5 min of exposure, thereby rendering the EEC inoperative. In contrast, when the chassis wall is made of stainless steel, all components and internal electronics remain functional throughout the initial 5 min thermal shock period. Experimental results show that the temperature evolution and component failure patterns under both scenarios align well with the simulation outcomes, thus validating the model’s accuracy. Full article

This study aims to explore the factors and mechanisms influencing the low-carbon development of Green Port Collection and Distribution Systems (GPCDSs) and to identify effective pathways and policy approaches to promote such development. Given the limited prior research integrating low-carbon policies, energy structure, and transportation systems, this study combines these three dimensions into a unified analytical framework. A scenario-based system dynamics model of GPCDS low-carbon development is established, incorporating factors such as low-carbon policies, energy structure, and transportation structure. The control variable method is employed to examine system behavior under 13 scenarios. The results indicate that freight subsidy policies and the internalization of carbon emission costs make the most substantial contributions to low-carbon development in GPCDS, yielding CO₂ emission reductions of 14.3% and 15.7%, respectively. Additionally, improvements in port railway infrastructure contribute to a 6.4% reduction in CO₂ emissions. In contrast, carbon taxes and energy structure adjustments have relatively limited effects, likely due to the delayed responsiveness of fossil fuel-dependent transportation sectors to pricing signals and the inherent inertia in transitioning energy systems. Full article

ESG serves as a key metric for measuring corporate sustainability, but divergence among rating agencies has led to uncertainty in such an assessment. This investigation identifies ESG rating divergence as a critical catalyst for corporate digital transformation, establishing empirical analysis through a robust positive correlation between the heterogeneity in sustainability assessments and organizational digitalization intensity. Comprehensive robustness examinations and endogeneity controls substantiate the persistent significance of this relationship. Mechanistically, such divergence drives technological adaptation by restructuring the R&D team composition and elevating capital allocation toward innovative initiatives. Contextual heterogeneity manifests through amplified effects in firms with elevated analyst scrutiny and stringent internal governance, whereas pollution-intensive enterprises exhibit significant effect suppression. These findings collectively advance theoretical frameworks concerning ESG evaluation economics and digital transformation drivers, while furnishing actionable implementation blueprints for corporate digitization strategists. Full article

With the increasing penetration of distributed generation and the diversification of electrical equipment, distribution networks face issues like three-phase unbalance and harmonic currents, while the voltage stability and inertia of the grid-connected system also decrease. A certain amount of energy storage is needed in a Distribution Static Synchronous Compensator (DSTATCOM) to manage power quality and actively support voltage and inertia in the network. This paper first addresses the limitations of traditional $dq0$ compensation algorithms in effectively filtering out negative-sequence twice-frequency components. An improved $dq0$ compensation algorithm is proposed to reduce errors in detecting positive-sequence fundamental current under unbalanced three-phase conditions. Second, considering the impedance ratio characteristics of the distribution network, while reactive power voltage regulation is common, active power regulation is more effective in high-resistance distribution networks. A grid-forming model-based active and reactive power coordinated voltage regulation method is proposed. This method uses synchronous control to establish a virtual three-phase voltage internal electromotive force, forming a comprehensive compensation strategy that combines power quality improvement and active voltage support, exploring the potential of energy storage DSTATCOM applications in distribution networks. Finally, simulation and experimental results demonstrate the effectiveness of the proposed control method. Full article

The emerging sesame (Sesamum indicum L.) industry in Australia faces potential threats from multiple pre-harvest diseases and pests, which will necessitate an initiative-taking approach for pest management. Here we assess the diseases and pests most likely to impede the development of a viable Australian sesame industry. Drawing on the international literature, we also consider the management approaches most likely to be viable and identify key research gaps necessary for effective and sustainable crop protection. More than sixty-seven plant pathogens have been identified worldwide that cause diseases in sesame, with some being observed to be major in Australia. Part of this review aims to provide an extensive overview of previous research on sesame and its diseases, shedding light on the evolving knowledge within sesame research, emerging trends, and the current state of understanding on the topic as it applies to Australia. Among the hundreds of pests reported to attack sesame internationally, this review identifies fifty-six pest taxa that are established in, or native to, Australia. We rank those most likely to be serious based on overseas damage levels and observations from recent trial plantings in Northern Australia. Chemical control methods have demonstrated efficacy overseas but are associated with concerns over resistance and environmental impact. Extremely limited numbers of pesticides are currently registered for pest or disease control in sesame by the Australian Pesticides and Veterinary Medicines Authority so non-chemical methods will be important. These include botanical, biological, cultural, and physical control approaches. This review underscores the need for continued research and tailored plant protection strategies to optimize sesame. Full article

This paper presents some of the most significant findings in the design of a hydraulic servomechanism for flight controls, which were primarily achieved by the first author during his activity in an aviation institute. These results are grouped into four main topics. The first one outlines a classical theory, from the 1950s–1970s, of the analysis of nonlinear automatic systems and namely the issue of absolute stability. The uninformed public may be misled by the adjective “absolute”. This is not a “maximalist” solution of stability but rather highlights in the system of equations a nonlinear function that describes, for the case of hydraulic servomechanisms, the flow-control dependence in the distributor spool. This function is odd, and it is therefore located in quadrants 1 and 3. The decision regarding stability is made within the so-called Lurie problem and is materialized by a matrix inequality, called the Lefschetz condition, which must be satisfied by the parameters of the electrohydraulic servomechanism and also by the components of the control feedback vector. Another approach starts from a classical theorem of V. M. Popov, extended in a stochastic framework by T. Morozan and I. Ursu, which ends with the description of the local and global spool valve flow-control characteristics that ensure stability in the large with respect to bounded perturbations for the mechano-hydraulic servomechanism. We add that a conjecture regarding the more pronounced flexibility of mathematical models in relation to mathematical instruments (theories) was used. Furthermore, the second topic concerns, the importance of the impedance characteristic of the mechano-hydraulic servomechanism in preventing flutter of the flight controls is emphasized. Impedance, also called dynamic stiffness, is defined as the ratio, in a dynamic regime, between the output exerted force (at the actuator rod of the servomechanism) and the displacement induced by this force under the assumption of a blocked input. It is demonstrated in the paper that there are two forms of the impedance function: one that favors the appearance of flutter and another that allows for flutter damping. It is interesting to note that these theoretical considerations were established in the institute’s reports some time before their introduction in the Aviation Regulation AvP.970. However, it was precisely the absence of the impedance criterion in the regulation at the appropriate time that ultimately led, by chance or not, to a disaster: the crash of a prototype due to tailplane flutter. A third topic shows how an important problem in the theory of automatic systems of the 1970s–1980s, namely the robust synthesis of the servomechanism, is formulated, applied and solved in the case of an electrohydraulic servomechanism. In general, the solution of a robust servomechanism problem consists of two distinct components: a servo-compensator, in fact an internal model of the exogenous dynamics, and a stabilizing compensator. These components are adapted in the case of an electrohydraulic servomechanism. In addition to the classical case mentioned above, a synthesis problem of an anti-windup (anti-saturation) compensator is formulated and solved. The fourth topic, and the last one presented in detail, is the synthesis of a fuzzy supervised neurocontrol (FSNC) for the position tracking of an electrohydraulic servomechanism, with experimental validation, in the laboratory, of this control law. The neurocontrol module is designed using a single-layered perceptron architecture. Neurocontrol is in principle optimal, but it is not free from saturation. To this end, in order to counteract saturation, a Mamdani-type fuzzy logic was developed, which takes control when neurocontrol has saturated. It returns to neurocontrol when it returns to normal, respectively, when saturation is eliminated. What distinguishes this FSNC law is its simplicity and efficiency and especially the fact that against quite a few opponents in the field, it still works very well on quite complicated physical systems. Finally, a brief section reviews some recent works by the authors, in which current approaches to hydraulic servomechanisms are presented: the backstepping control synthesis technique, input delay treated with Lyapunov–Krasovskii functionals, and critical stability treated with Lyapunov–Malkin theory. Full article

This study presents the first quantitative comparison of catastrophic phase inversion behavior of water-in-oil emulsions stabilized by nanocrystalline cellulose (NCC) and molecular surfactants with different headgroup charge types: anionic (sodium dodecyl sulfate referred to as SDS), cationic (octadecyltrimethylammonium chloride referred to as OTAC), nonionic (C12–14 alcohol ethoxylate referred to as Alfonic), and zwitterionic (cetyl betaine referred to as Amphosol). By using conductivity measurements under controlled mixing and pendant drop tensiometry, this study shows that NCC markedly delays catastrophic phase inversion through interfacial jamming, whereas surfactant-stabilized systems exhibit concentration-dependent inversion driven by interfacial saturation. Specifically, NCC-stabilized emulsions exhibited a nonlinear increase in the critical aqueous phase volume fraction required for inversion, ranging from 0.253 (0 wt% NCC) to 0.545 (1.5 wt% NCC), consistent with enhanced resistance to inversion typically associated with the formation of rigid interfacial layers in Pickering emulsions. In contrast, surfactant-stabilized systems exhibited a concentration-dependent inversion trend with opposing effects. At low concentrations, limited interfacial coverage delayed inversion, while at higher concentrations, increased surfactant availability and interfacial saturation promoted earlier inversion and favored the formation of oil-in-water structures. Pendant drop tensiometry confirmed negligible surface activity for NCC, while all surfactants significantly lowered interfacial tension. Despite its weak surface activity, NCC imparted strong coalescence resistance above 0.2 wt%, attributed to steric stabilization. These findings establish distinct mechanisms for governing phase inversion in particle- versus surfactant-stabilized systems. To our knowledge, this is the first study to quantitively characterize the catastrophic phase inversion behavior of water-in-oil emulsions using NCC. This work supports the use of NCC as an effective stabilizer for emulsions with high internal phase volume. Full article