Stable System Research Articles

Omega-3 and unsaturated fatty acid enrichment of shrimp oil: Preparation, characterization, and its application in salad dressings

The effect of various lipase hydrolytic conditions on DHA/EPA and unsaturated fatty acids (USFAs) enrichment of shrimp (Litopenaeus vannamei) oil (SO) extracted from hepatopancreas was investigated. DHA/EPA and USFAs levels increased (40.96/22.61 and 27.83%, respectively) under optimized hydrolytic conditions of 20 U lipase, DMSO as a solvent (0.2:0.5), DMSO to water for the substrate mixture (SM), and water to SM (0.4:1) for 2 h at 50 °C. n3FAs and USFAs enriched shrimp oil (n3SO) were added to salad dressing (SD) at various concentrations (0, 5, 10, and 15%) (CON, SD5, SD10, and SD15, respectively) to offset the concentration of soybean oil. The addition of n3SO imparted an attractive orange color, enhancing the organoleptic properties of the SD, as indicated by higher likeness scores for color and appearance attributes than CON and commercial SD (CM). Samples added with n3SO exhibited a more uniform pattern and distribution of oil droplets, suggesting the formation of a stable emulsion system. The result was also supported by its enhanced viscoelastic and flow properties than the CON and CM. Overall, DHA/EPA enriched SO could be potential supplement or functional ingredient in SDs or other emulsion related products with superior health benefits.

CRISPR-Cas9 Mediated Gene Deletion in Human Pluripotent Stem Cells Cultured Under Feeder-Free Conditions.

The CRISPR-Cas9 system for genome editing has revolutionized gene function studies in mammalian cells, including stem cells. However, the practical application of this technique, particularly in pluripotent stem cells, presents certain challenges, such as being time- and labor-intensive and having low editing efficiency. Here, we describe the generation of a CRISPR-mediated gene knockout in a human embryonic stem cell (hESC) line stably expressing sgRNAs for the L2HGDH gene, using a highly efficient and stable lentiviral-mediated gene delivery system. The sgRNAs targeting exon 1 of the L2HGDH gene were chemically synthesized and cloned into the lentiCRISPR v2-puro vector, which combines the constitutive expression of sgRNAs with Cas9 in a highly efficient single-vector system to achieve higher lentiviral titers for hESC infection and stable selection using puromycin. Puromycin-selected cells were further expanded, and single-cell clones were obtained using the limited dilution method. The single clones were expanded, and several homozygous knockout clones for the L2HGDH gene were obtained, as confirmed by a 100% reduction in L2HGDH expression using Western blot analysis. Furthermore, using MSBSP-PCR, the CRISPR mutation site was mapped upstream of the PAM recognition sequence of Cas9 in the selected homozygous clones. Sanger sequencing was performed to analyze the exact insertions/deletions, and functional characterization of the clones was conducted. This method produced a significantly higher percentage of homozygous deletions compared to previously reported non-viral gene delivery methods. Although this report focuses on the L2HGDH gene, this robust and cost-effective approach can be used to create homozygous knockouts for other genes in pluripotent stem cells for gene function studies.

Backstepping boundary control for the Rayleigh model with a class of boundary conditions

Abstract This paper presents that a boundary feedback controller is proposed to stabilize the Rayleigh model. Firstly, we transform the initial equation into a second-order hyperbolic equation. Secondly, by using a backstepping integral coordinate transformation, we transform the simplified second-order hyperbolic equation into a stable target system. Meanwhile, a gain kernel equation will be generated during the conversion process. By solving the gain kernel equation, our goal is to design the controller based on information from the gain kernel. Finally, simulation results demonstrate the effectiveness of our designed controller.

Thermo sensitive and pH responsive surface modulated transdermal green tea nanogel: Structural, physiochemical and in vitro safety investigations

An altered simplistic biomimetic whole green tea extract-loaded nanogel (GE-C-NGL) was fabricated possessing pH-responsive and temperature-dependent intracellular transdermal nanotherapy. A biocompatible chitosan nanogel subsequently surface modified with oleic acid aiding Pluronic 127 discharging green tea extract on transdermal delivery was evaluated in light of structural, physiochemical, thermal, and in vitro toxicological factors by optical class, index class and spectrophotometrically class, and in vitro cell line toxicological evaluations, which precisely elaborated the nanosize particle size range and significant drug entrapment suggesting a spherical and thermo stable nanogel system. Additionally, sustained drug release configuration is displayed in mildly acidic conditions (pH 6) signifying ultra-pH sensitivity of GE-C-NGL. Moreover, strong mucin binding ability, pH-dependent swelling efficiency, negligible hemolytic ratio, and high antioxidant activity were obtained for enhanced transdermal efficacy. The comprehensive augmented polymeric blend transdermal nanogel, in light of the above preclinical biological and toxicological evaluations, evidently targets transdermal potential with promising bacterial biodegradable nanodrug therapy in clinical platforms.

Optimization of titanium alloy bipolar plate performance in proton exchange membrane water electrolysis with Cr/W/diamond-like carbon coating

The operating environment for bipolar plates in proton exchange membrane water electrolysis (PEMWE) systems is highly challenging, characterized by high electrical potential, acidic pH, and elevated temperatures. Bipolar plates must possess high corrosion resistance and electrical conductivity to ensure stable and efficient system perfomance. Therefore, surface coatings are essential to decelerate oxidation on the substrate surface, preventing a significant increase in interfacial contact resistance (ICR). This investigation applied a Cr/W/diamond-like carbon (DLC) coating to titanium alloy (Ti-6Al-4 V, also known as TC4) surfaces using magnetron sputtering. The multilayer coating system was designed to enhance electrical conductivity and corrosion resistance of the bipolar plate while ensuring good coating adhesion. At potentials of 1.2 V, 1.5 V, and 1.8 V, the current densities measured during potentiostatic polarization were 0.11 μA·cm-2, 0.19 μA·cm-2, and 0.4 μA·cm-2, respectively, showing a significant reduction compared to the TC4 matrix and demonstrating long-term stability. The Cr/W/DLC-coated TC4 bipolar plates exhibited an ICR of 16.98 mΩ/cm2 under a contact pressure of 1.4 MPa. These results suggest that the coating provides exceptional corrosion resistance under PEMWE operating conditions while retaining electrical conductivity.

Experimental study of a distributed active noise control system with multi-device nodes based on augmented diffusion strategy.

Recently, distributed active noise control (DANC) algorithms have been explored as a way to reduce computational complexity while ensuring system stability, thereby outperforming conventional centralized and decentralized algorithms. Most existing DANC algorithms assume that each node has only one pair of loudspeaker and microphone, limiting their flexibility in practical applications. In contrast, this paper proposes a DANC algorithm with general multi-device nodes based on the recently developed augmented diffusion strategy, allowing flexible and scalable ANC applications. A real-time distributed ANC system based on a multi-core digital signal processor platform is developed in order to compare the control performance of the proposed extended augmented diffusion algorithm with that of existing centralized, decentralized and augmented diffusion algorithms. Real-time experiments demonstrate that the proposed algorithm exhibits noise reduction performance consistent with that of the centralized algorithm while achieving lower global computational complexity and avoiding the system instability risk of the decentralized algorithm. Further, the new algorithm improves convergence speed and reduces the global communication cost compared to the previous augmented diffusion algorithm. Experimental results indicate the application potential of the proposed DANC algorithm for a generalized system configuration.

Improved state transition algorithm for hybrid power system reactive power optimization using filter techniques

Abstract Reactive power optimization in power systems is crucial for their normal and efficient operation. However, with the increasing prevalence of active current and direct current (AC-DC) hybrid power grids, existing optimization methods face issues such as poor adaptability, low efficiency, insufficient accuracy, and inadequate convergence. To address these problems, this paper proposes a reactive power optimization model based on an improved state transition algorithm (STA) utilizing filter techniques. The optimization model considers operational costs associated with adjusting transformer tap positions, switching reactive power compensation capacitors, regulating generator terminal voltages, and adjusting active power in DC transmission. Simulation results demonstrate that this method can reduce system losses and voltage control costs while ensuring stable system operation, thus improving the reactive power distribution in AC-DC hybrid transmission systems.

Enhanced behavioral impact of optimized bupropion-encapsulated bilosomes over traditional niosomes treating depression.

Bupropion (Bpn), an FDA-approved NDRI (norepinephrine-dopamine reuptake inhibitor), poses risks of seizures and liver failure due to its stimulant properties, necessitating the development of alternative formulations. This research aims to develop a Bpn nanoformulation within bilosomal vesicles to enhance therapeutic efficacy at lower doses, using three bile salts, span 20 surfactants, and cholesterol via thin-film hydration. Optimization of bilosomal stability is achieved by trialing various ingredient concentrations, identifying a surfactant-to-cholesterol-to-bile salt ratio of 1.5:1:0.17µM, with sodium cholate (B.SCF) yielding the most stable system. Bpn encapsulated in the optimized bilosomal vesicle (Bpn@B.SC F) demonstrated high encapsulation efficiency of 78.142 ± 11.07% and drug-retaining capacity compared to the niosomal system. The in vitro and in vivo toxicity profile of the product is superior to the niosomal system and shows negligible toxicity with a viability rate of not less than 95%, with a sustained release profile in artificial cerebrospinal fluid (ACSF). In vivo, behavioral analysis on zebrafish revealed that Bpn@B.SC F treatment more effectively improved depressive behavior compared to free Bpn and other treatments, evidenced by increased exploration rates and reduced irregular movements, as shown through statistical and trajectory data. Hence, it is concluded that the bilosomal structure, compared to the niosomal system, is a better carrier of drugs to achieve brain delivery and improve mood.

Does the Disclosure of Proprietary Information About Loan Losses Pose a Threat to Financial Stability?

AbstractConcerns have been expressed that public disclosure of outcomes from regulatory inspections of banks could lead to contagion and instability in the financial systems. This paper exploits Denmark's system of open inspection reports to analyze whether announcements of required increases in loan loss reserves by the Danish supervisory authorities, following an ordinary bank inspection, lead to contagion in financial markets. We find strong evidence of negative returns for the announcing banks over the period 2009–2020, suggesting that inspection reports containing proprietary information about loan losses provide value-relevant news to investors. We also find statistically significant contagion effects in the share price reactions among non-announcing peer banks. However, the reactions of other, non-affected banks are mild and confined to smaller banks, which is reassuring from a systemic risk perspective. Overall, our findings support the use of accounting disclosures as a policy tool for bank supervisors.

Interest rate risk in banking book management at commercial banks in Vietnam

Interest rate risk is potentially averse to a commercial bank's trading book and banking book. The sharp and rapid volatility of interest rates can push commercial banks to fall into difficult situations, thus leading to instability of the whole banking system. Therefore, interest rate risk in banking book (IRRBB) management plays a vital role in banking operations. This paper analyzes the current management of IRRBB at 21 commercial banks in Vietnam by doing in-depth interviews and questionnaires. The finding indicates that the level of IRRBB management of commercial banks in Vietnam is mostly relatively completed or inadequate, with the highest levels belonging to international commercial banks and the banks that implement Basel II. Furthermore, the study also executes a simulation of IRRBB management at one commercial bank according to current regulations of the State Bank of Vietnam. Based on the selected interest rate scenarios, the capital requirement for IRRBB is calculated, which is the actual simulation for commercial banking in implementing the IRRBBB framework. Finally, to improve the effectiveness of IRRBB management in Vietnam, some implications for the State Bank of Vietnam and commercial banks are provided.

Benchmarking Performance Indices of Electrochemical CO2 Reduction to Ethylene Based on Prospective Life Cycle Assessment for Negative Emissions.

To mitigate global warming to the most ambitious targets, it is necessary to remove CO2 from the atmosphere and reduce fossil fuels use. The electrochemical conversion of CO2 to ethylene (C2H4) as a basic chemical is a promising technology that meets both requirements; however, its life cycle CO2 emissions remain inconclusive because of varying assumptions in the performance indices. This study aimed to set benchmarks for the four most sensitive indices to achieve -0.5 t-CO2/t-C2H4 by calculating net greenhouse gas (GHG) emissions through a prospective life cycle assessment of a model system including CO2 capture, CO2 enrichment, electrochemical conversion, CO2 recycling, and cryogenic separation. As a result, the electrochemical conversion process was the hotspot of life cycle emissions, and representative benchmarks were determined as follows: cell voltage, 3.5 V; C2H4 Faraday efficiency, 70 %; conversion rate, 20 %; and electrochemical CO2 recycling energy, 2.2 GJ/t-CO2. The gaps between the benchmarks and current top data of cell voltage and Faraday efficiency were <10 %, and suppressing the performance degradation for up to one year was found to be a critical requirement. These results can direct research towards the development of a year-round stable system, rather than further improving the performance indices.

Financial Performance and Competitor analysis: Evidence on Starbucks

This research mainly studied and analysed all aspects of Starbucks finance, focussed on investigating the development trend of Starbucks in 2022 and 2023, conducted a brief study and discussion on the company’s finances, and obtained several important conclusions through a series of data. Several vital data show some characteristics of the company’s operation and management, which brings a lot of meaningful utilisation value and is worth learning from and thinking about. In the years after the COVID-19 pandemic, Starbucks was able to quickly restore and develop its economic system thanks to its stable system and management system. This article will also study the economic benefits brought by the management system. In addition, the article also collects data from two competitors in the same industry as Starbucks and reflects the advantages and disadvantages of Starbucks in the industry through comparison. Among them, the most noteworthy is the research on several economic methods carried out by Starbucks, which shows Starbucks’ stable economic system and management methods.

Model for Local Cavitation Instabilities in 2-Bladed Turbopump Inducers

Abstract Various local cavitation instabilities in turbopump inducers (e.g., alternate blade cavitation, super-synchronous rotating cavitation, etc.) have previously been experimentally identified. However, a model, which is capable of predicting such local instabilities is still lacking. Therefore, a new model, which models an N-bladed inducer as a system of N coupled mass- spring-damper systems, is presented to predict post-onset behavior of alternate blade cavitation instabilities. The model predicts alternate blade cavitation to occur. As the flow coefficient is decreased, the model predicts the magnitude of alternate blade cavitation to first increase and then decrease, and then finally vanish. If the flow coefficient is further decreased beyond the range of alternate blade cavitation, sudden increase in equilibrium incidence is predicted. All of these predictions agree with the previous experimental findings. Furthermore, simultaneous in-phase oscillations of the blade cavities are predicted during alternate blade cavitation. These in-phase oscillations of the cavities correspond to the surge mode oscillation, which had been previously mistakenly categorized as a global (system) instability. Finally, it is proposed that the above post-onset behaviors of alternate blade cavitations are general in two-bladed inducers, as long as the change in incidence on the following blade has a local minimum when it is expressed as a function of leading blade's incidence.

In situ growth of L012-reduced gold nanoparticles-loaded graphitic carbon nitride nanocomposite for potential-resolved ratiometric electrochemiluminescence analysis

BackgroundMost electrochemiluminescence (ECL) analytical methods involve only changes in one single signal, which greatly limits their high sensitivity and stability for applied research. Potential-resolved electrochemiluminescence (PRECL), which provides calibrated analysis by self-correcting signal responses from dual channels, has attracted great interest in recent years. However, research on PRECL nanomaterials is still at an early stage. It is critical to develop a novel PRECL nanocomposite with high intensity in light emission, high resolution in potential separation, and reduced complexity in reaction systems for accurate detection. ResultsHere, a novel PRECL nanocomposite, L012-Au/g-C3N4, was synthesized by in situ growth of L012-reduced gold nanoparticles (L012-Au) on the surface of graphitic carbon nitride (g-C3N4) nanosheets. The g-C3N4 nanosheets served as effective carriers for L012 molecules and L012-Au, as well as efficient cathodic ECL emitters. With the addition of a single co-reactant (K2S2O8), two fully separated ECL peaks were observed around −1.3 V (ECL-1) and +0.6 V (ECL-2) at neutral conditions. The catalytic character of the incorporated gold nanoparticles accelerated the anodic ECL reaction and greatly enhanced the ECL intensity. Furthermore, an ECL mechanism based on the competitive relationship between K2S2O8 and dissolved oxygen was proposed. When dopamine (DA) was introduced into the PRECL reaction system, ECL-1 remained essentially unchanged, while ECL-2 intensity was significantly reduced. By analyzing the intensity ratio of ECL-2 to ECL-1 (I2/I1) to the detecting target, a ratiometric DA sensor with high sensitivity and stability was successfully constructed. SignificanceA nanocomposite L012-Au/g-C3N4 that can induce high-intensity ECL with two separated potentials in each polarity has been prepared by a simple synthetic method. The developed ratiometric sensor can eliminate systematic errors and improve accuracy. In addition, the multifunctionality of the nanocomposite and the necessity of only one co-reactant for neutral-condition ECL greatly reduced the reaction complexity. Our work offers new PRECL solutions to design highly sensitive and stable multi-response detection systems for in vitro diagnostics.

Eight year Follow-Up Data on a Leadless Pacing System Real life experience in comparison to data of the prospective trial

Abstract Introduction The Micra leadless intracardiac pacing system has been introduced and implemented into clinical routine in 2015, with its next generation MICRA AV in 2020. Feasibility, implantation safety, and acute success have been proven in the setting of controlled studies. Even apart from controlled studies, this new technology was beneficial for the individual patient. We aimed to report our single center follow-up (FU) data with a follow-up of up to six years. Methods In 292 patients (146 men; age: 81±5,7 y), Micra implantation was performed. Pacemaker interrogation was performed one to seven days after implantation and during FU (1; 3; 6, then every 6 month) up to 84 months. Data were assessed in a real-life setting and compared with existing data of a controlled prospective trial. Results The implantation was successful in all 292 attempts with only one pericardial effusion as major complication. During follow up there were two patients developing severe heart failure symptoms resulting in an implantation of a CRT-device and switching of the leadless pacemaker system. The average acute thresholds, sensing and impedance after system release were: 0.57±0.34V@0.24ms; 10,02±3,96mV and 752±1201Ohm. During follow up of up to 8 years neither, pacemaker failure, nor infections were reported. Measurements were reevaluated for long-term thresholds, sensing and impedance: 0.75 ± 0.38V @ 0.24 ms; 18,38 ±2,75 mV and 525 ± 102 Ohm. During eight years, no significant changes from acute to long-term measurements were detectable. In comparison to the controlled trial, our measurements of this real-life cohort were very similar. Conclusion In a real-life setting, the implantation of the leadless Micra system demonstrates a high rate of implantation success without major complications. We were also able to show stable long-term system parameters in the clinical setting of up to seven years of follow up with a very good battery longevity of about 12,3 years.

Intelligent Control Algorithms for Enhanced Frequency Stability in Single and Interconnected Power Systems

Ensuring stable power system performance is crucial for reliable grid operation. This study assesses various Load Frequency Control (LFC) strategies, including conventional PID, pole placement, Genetic Algorithm (GA)-optimized PID, Particle Swarm Optimization (PSO)-optimized PID, and an Artificial Neural Network (ANN)-based controller, in single and interconnected power grids. The results reveal that GA- and PSO-optimized PID outperform conventional methods, offering minimal overshoot and fast settling times. Pole placement strikes a balance between response time and stability, while the ANN controller demonstrates adaptability and quick rise times but exhibits higher overshoot and longer settling times compared to the optimization techniques. Tie-line bias control aids in frequency stabilization but presents challenges with overshoot and prolonged settling times. Notably, PSO-optimized PID emerges as a promising solution, effectively mitigating overshoot and achieving rapid frequency recovery. This study underscores the importance of tailored control strategies for optimal LFC, which are essential for enhancing power system stability and efficiency. Future research should explore the potential of advanced techniques, such as deep learning and reinforcement learning, to further improve control performance.

Optimal control design for power system stabilizer using a novel crow search algorithm dynamic approach

This paper proposes the first application of a novel improved metaheuristic optimization technique, dynamic crow search algorithm (DCSA) to find the optimal design of the power system stabilizer (PSS). Using the novel DCSA adaptive approach provides a global search capability as well as fastness and effectiveness to get the PSS best parameters under the search space constraints and local optimums. Moreover, PSS parameters has a crucial effect on power system stability that is a major nowadays engineering concern, where its best parameters could make a difference by damping small-signal stability oscillations effectively and in the smallest amount of time if they are obtained through a robust algorithm. As a result, PSS will prevent large types of instabilities which could reach up to some generation stations shedding. The novel proposed algorithm is for first time used and tested under different power system instabilities scenarios by using single-machine infinity bus model over multiple operating conditions to damp out perturbation signals effectively by means of getting optimal PSS design parameters, where Integral absolute error (IAE) performance index is used as an objective function to be minimized. Additionally, results obtained by the proposed approach are compared with those obtained by other methods. It is observed that the proposed method has better convergence characteristics and robustness compared to the original version and other comparison methods. It is revealed that the proposed adaptive method is able to improve the power system stability dynamics and damp out perturbation oscillations successfully.

Dynamic stability analysis of the aircraft electrical power system in the more electric aircraft concept

This paper presents the modelling and analysis process of the electrical power management system on board an electrified aircraft conforming to the More/All Electric Aircraft concept. The main objective of the study is to assess the stability of the Electric Power Distribution System under different operational conditions, including the aspect of constant power loads. The paper describes the structure of the system, in which the key role is played by a synchronous generator and a three-phase rectifier converting alternating current AC into direct current DC. To solve the problem, modeling methods in the Matlab/Simulink environment were used, which enabled the analysis of the dynamic properties of the system and the assessment of stability under various types of loads. The obtained test results show that the presence of constant power loads can lead to instability in the EPDS system, manifested by voltage and current oscillations exceeding the standards specified in the MIL-STD-704E standard. The paper also provides tools for predicting system stability without the need to conduct full stability tests, which is important for the design of modern aviation power systems. The final section of the work presents the research results obtained and the resulting significant insights and practical conclusions.

Micro-integrated crossed-beam optical dipole trap system with long-term alignment stability for mobile atomic quantum technologies.

Quantum technologies extensively use laser light for state preparation, manipulation, and readout. For field applications, these systems must be robust and compact, driving the need for miniaturized and highly stable optical setups and system integration. In this work, we present a micro-integrated crossed-beam optical dipole trap setup, the µXODT, designed for trapping and cooling 87Rb. This fiber-coupled setup operates at 1064 nm wavelength with up to 2.5 W optical power and realizes a free-space crossed beam geometry. The µXODT precisely overlaps two focused beams (w0 ≈ 33µm) at their waists in a 45° crossing angle, achieving a position difference of ≤3.4µm and a 0.998 power ratio between both beams with long-term stability. We describe the design and assembly process in detail, along with optical and thermal tests with temperatures of up to 65°C. The system's volume of 25ml represents a reduction of more than two orders of magnitude compared to typically used macroscopic setups while demonstrating exceptional mechanical robustness and thermal stability. The µXODT is integrated with an 87Rb 3D MOT setup, trapping 3×105 atoms from a laser-cooled atomic cloud, and has shown no signs of degradation after two years of operation.

Exploring the potential of peach gum polysaccharides in β-carotene emulsions encapsulation during storage

Oil-in-water (O/W) emulsions have emerged as a viable method for encapsulating β-carotene. To achieve stable emulsion systems, the development of latent emulsifiers is essential. This study collected three peach cultivars (Mixture cultivar (MC), Zhonghpan 11# (ZP11), and Yingqing (YQG)) to extract peach gum polysaccharides (PGP) for the encapsulation of β-carotene without the need for additional emulsifiers. The research aimed to investigate the emulsions' physicochemical stability (including particle size, zeta potential, turbidity, color, and retention rate of β-carotene (RR)) during storage. The findings revealed that the ZP11 emulsion exhibited the highest emulsion efficiency (EE) at 89.08% and displayed a more vibrant color. After 35 days of storage, YQG emulsion exhibited better emulsion stability with the highest zeta-potential (>35 mV, negative), RR of β-carotene (43.44%), and longest half-life period (t1/2, 32.31d) among three cultivars. Correlation analysis showed that molecular weight (Mw), polydispersity coefficient (Mw/Mn), and arabinose (Ara) of PGP would have an influence on its emulsifying capacity and stability of β-carotene emulsion. The information was significant for PGP of great potential as an emulsifier and stabilizer to provide possibility regarding designing a proper delivery system.