Formation Protocol Research Articles

Adaptive connectivity-preserving formation control with a dynamic event-triggering mechanism

Connectivity preservation for real-life multi-agent systems is key to designing an effective and reliable control algorithm to achieve desired objectives. But the coexistence of system nonlinearities and uncertainties makes it difficult for the algorithm design, and especially in the event-triggered setting, such difficulty becomes severer due to the demand for integration of multiple ingredients. This paper focuses on proposing an adaptive connectivity-preserving formation control strategy that incorporates a dynamic event-triggering mechanism, in the scenario of the unknown control directions and intrinsic nonlinearities coupling with parameter uncertainties. First, a cluster of potential functions serving as control barrier functions are given to maintain the prescribed connectivity of communication graph. Second, two types of dynamic gains (one type is based on a Nussbaum function) are introduced for agents to cope with the system nonlinearities, uncertainties and the adverse effect of the execution error. As such, an adaptive event-triggered formation protocol is constructed such that the desired formation with connectivity preservation is achieved while a positive minimum inter-execution interval is ensured for each agent to avoid Zeno behavior. Particularly, the threshold in the developed event-triggering mechanism is dynamically adjusted online, rather than static, which better improves resource efficiency. A simulation example is given to demonstrate the effectiveness and advantage of the proposed strategy.

On the Use of Image Analysis for Hematocrit Evaluation in Dried Blood Spots

Dried blood spots (DBSs) are formed by collecting a small sample of blood on specialized filter paper and allowing it to dry naturally. Various domains of life sciences and drug research extensively use DBSs as a sampling technique. The “Hematocrit (Ht) effect” affects assay bias, and several strategies have been put forth to deal with it, including the correction of quantified concentrations using an appropriate correction factor. The approach was previously applied, following the utilization of an image processing algorithm developed in Matlab® to derive a reliable equation correlating DBS areas to Ht% values. The present work looks more closely at the application of image analysis to the evaluation of Ht in DBS samples. Utilizing image analysis software, DBS samples with known Ht values were processed. Preparation of cards has followed a previously developed protocol for the appropriate formation of uniform area DBSs, irrespective of Ht. The resulting areas showed close resemblance to the respective theoretical areas calculated by applying the correlation equation. Following that, the equation was utilized to determine the Ht values for each sample, and a comprehensive comparison of measured versus calculated Ht was carried out using various statistical approaches for method comparison. The results demonstrated a strong correlation, suggesting the method’s viability in estimating Ht for unknown DBS samples.

Standardized research on multifunctional beacon multi-sensor data acquisition and transmission

Abstract This paper discusses the research on the standardization of data acquisition and transmission for multifunctional beacon systems. The multifunctional beacon system integrates various types of sensing devices and can provide real-time, comprehensive and accurate marine environment and navigation information for ships and shore-based users. However, the system currently faces challenges such as non-uniform data formats and communication protocols, low hardware standardization and integration, and data and network security risks. In order to solve these problems, this paper puts forward the solution of “standard terminal for data acquisition and transmission”, which achieves the compatibility of equipment interface, unified data format, and reliable information security. It lays the foundation for the standardization of multi-purpose beacon system. Through modular design and standardized packaging, the performance, reliability and efficiency of the hardware of multi-purpose beacons are improved, the development and maintenance costs are reduced, and the flexibility of the system is enhanced. The “Standard Terminal for Data Acquisition and Transmission” is applied to the multi-purpose beacon system, and interfaces and integrates with the existing “Operation Management System for Navigation Guarantee” to realize a unified platform for multi-purpose beacons. This research helps to promote the formulation of multi-purpose beacon data format and communication protocol standards at the national or industrial level, provides important reference for the formulation of international standards, and is of great significance in promoting the standardized development and application promotion of multi-purpose beacon technology.

A Hybrid 2D-to-3D in vitro Differentiation Platform Improves Outcomes of Cerebral Cortical Organoid Generation in hiPSCs.

Three-dimensional (3D) cerebral cortical organoids are popular in vitro cellular model systems widely used to study human brain development and disease, compared to traditional stem cell-derived methods that use two-dimensional (2D) monolayer cultures. Despite the advancements made in protocol development for cerebral cortical organoid derivation over the past decade, limitations due to biological, mechanistic, and technical variables remain in generating these complex 3D cellular systems. Building from our previously established differentiation system, we have made modifications to our existing 3D cerebral cortical organoid protocol that resolve several of these technical and biological challenges when working with diverse groups of human induced pluripotent stem cell (hiPSC) lines. This improved protocol blends a 2D monolayer culture format for the specification of neural stem cells and expansion of neuroepithelial progenitor cells with a 3D system for improved self-aggregation and subsequent organoid development. Furthermore, this "hybrid" approach is amenable to both an accelerated cerebral cortical organoid protocol as well as an alternative long-term differentiation protocol. In addition to establishing a hybrid technical format, this protocol also offers phenotypic and morphological characterization of stage-specific cellular profiles using antibodies and fluorescent-based dyes for live cell imaging. © 2024 Wiley Periodicals LLC. Basic Protocol 1: hiPSC-based 2D monolayer specification into neural stem cells (NSCs) Basic Protocol 2: Serial passaging and 2D monolayer expansion of neuroepithelial progenitor cells (NPCs) Support Protocol 1: Direct cryopreservation and rapid thawing of NSCs and NPCs Basic Protocol 3: Bulk aggregation of 3D neurospheres and accelerated cerebral cortical organoid differentiation Alternate Protocol 1: Bulk aggregation of 3D neurospheres and long-term cerebral cortical organoid differentiation Support Protocol 2: High-throughput 3D neurosphere formation and 2D neurosphere migration assay Support Protocol 3: LIVE/DEAD stain cell imaging assay of 3D neurospheres Support Protocol 4: NeuroFluor NeuO live cell dye for 3D cerebral cortical organoids.

A Comparison of Standard SEI Growth Models in the Context of Battery Formation

Growth of the Solid Electrolyte Interphase (SEI) layer on negative electrode particles during the formation cycle is one of the most complex and least understood steps of lithium-ion battery manufacturing. This initial SEI formation significantly impacts battery performance, lifetime, and degradation. Zero-dimensional models, which reduce the complexity of SEI’s morphology, material, and structure, are commonly used to study long-term SEI growth rates and capacity fade. These models are derived based on limiting mechanisms. We aim to compare the most common SEI growth models, focusing on the first few cycles at low C-rates representing formation protocols. Using consistent parameters across models, we seek to understand if they can capture the dynamics of SEI formation. We conducted qualitative comparisons with experimental measurements of Coulombic efficiency in 2032-type coin cells at low C-rate. Our analysis shows that the models predict SEI growth in the first cycle to be higher than in subsequent cycles. However, the difference between cycles in these models is insufficient to explain the experimental results, which indicate a capacity fade during the first cycle that is two orders of magnitude higher than in later cycles. This suggests new models are needed to accurately describe the physics of the formation cycle.

Effect of the Formation Rate on the Stability of Anode-Free Lithium Metal Batteries.

Anode-free Li-ion batteries (AFBs), where a Cu current collector is used to plate and strip Li instead of a classic anode, are promising technologies to increase the energy density of batteries. In addition, AFBs are safer and easier to manufacture than competing Li-metal anodes and solid-state batteries. However, the loss of Li inventory that occurs during the operation of AFBs limits their lifespan and practical application. In this study, we find that, in particular, the current density used during the formation of AFBs has a considerable impact on the cycling stability of the cell. We optimize the formation protocol based on experimental and computational observations of thresholds associated with morphological changes in the plated Li and the chemical composition of the solid-electrolyte interphase. Unlike graphite anodes, which require slow formation cycles, AFBs exhibit improved cycling behavior when formed at the highest current densities that avoid dendritic Li formation. We verify that this strategy for optimizing the formation current density is effective for three different electrolyte formulations and, therefore, provides a straightforward universal rationale to optimize the formation protocols for AFBs.

Formation control of high-order linear discrete-time multiple unmanned aerial vehicles systems in noisy environments

Formation control of high-order linear discrete-time multiple unmanned aerial vehicles (multi-UAVs) systems with multiplicative noises is studied in this article. Because of the existence of multiplicative noises, classical methods for discrete-time system control problems should be improved. Here, we develop a new discrete-time formation protocol for multi-UAVs systems. The stochastic Lyapunov stability theory and the positive definiteness theory of a generalized algebraic Riccati equation are then used to derive sufficient conditions for formation feasibility.

Towards Rational Design of Battery Formation Protocols: From Electrochemical Modeling to Factory Deployment

In battery manufacturing, the formation process is both paramount and problematic. It is paramount since all batteries undergo formation charging and aging steps to build a resilient solid electrolyte interphase (SEI) and to screen for defects. It is problematic because the formation process is expensive to operate, remains a major source of factory energy demand, requires larger factory footprints, and takes an order of magnitude longer than nearly every other manufacturing step. Despite the centrality of the formation process in battery manufacturing, steps taken to optimizing formation protocols remain ad-hoc in the absence of design principles and physical models.We highlight recent progress in developing a principled understanding of the SEI formation process applied towards industrial battery formation process (i.e. in the context of a full cell). We review a reduced-order electrochemical model of the formation process that captures first cycle charge dynamics and subsequent cycling and aging degradation behavior [1]. The model predicts measurable quantities such as first cycle efficiency (FCE) and irreversible thickness growth under multiple formation protocols. We discuss opportunities to integrate the electrochemical formation model with differential voltage analysis (DVA) to visualize the connection between first cycle charge dynamics from the perspective of shifting electrode stoichiometries [2] and comment on applications towards physics-informed battery lifetime prediction [3]. We finally share recent data elucidating the effect of formation temperature, pressure, and protocol on cycle life.

Improved Silicon/Graphite Composite Anode for High-Energy Li-Ion Battery

High-specific capacity of Silicon (~ reaching up to 3600 mAh/g corresponds to Li15Si4) and relatively higher lithiation potential (~0.4V Vs Li+; helpful in avoiding plating) makes it an ideal candidate for high-energy Li-ion batteries (LIBs). However, it is faced with severe issues like high crystallographic expansion (~320%), slow lithium diffusion, and high reactivity with electrolyte at higher SOCs. All of it leads to particle cracking, isolation, and electrode delamination resulting into poor cycle life performance. To harness the true potential of Silicon, we proposed an improvised Si/Gr composite anode balancing the high-specific capacity and cycle life. We investigated a novel binder formulation for Si-rich/Gr composite to enable high-specific capacity without compromising on life cycle. We demonstrated a robust and stable solid-electrolyte interface (SEI) formation by optimizing the electrolyte additive and formation protocol. Coupling our Si/Gr anode with high-energy Ni-rich cathode at appropriate capacity ratio (N/P) provides high-energy density (> 400 Wh/Kg) for LIBs.

Production and Multi-Parameter Live Cell Fluorescence Lifetime Imaging Microscopy (FLIM) of Multicellular Spheroids.

Multicellular tumor spheroids are a popular 3D tissue microaggregatemodel for reproducing tumor microenvironment, testing and optimizing drug therapiesand using bio- and nanosensors in a 3D context. Their ease of production, predictable size, growth, and observed nutrient and metabolite gradients are important to recapitulate the 3D niche-likecell microenvironment. However, spheroid heterogeneity and variability of their production methods can influence overall cell metabolism, viability, and drug response. This makes it difficult to choose the most appropriatemethodology, considering the requirements in size, variability, needs of biofabrication, and use as in vitro 3D tissue models in stem and cancer cell biology. In particular, spheroid production can influence their compatibility with quantitative live microscopies, such as optical metabolic imaging, fluorescence lifetime imaging microscopy (FLIM), monitoring of spheroidhypoxia with nanosensors, or viability. Here, a number of conventional spheroid formation protocols are presented, highlighting their compatibility with the live widefield, confocal, and two-photon microscopies. The follow-up imaging to analysispipeline with multiplexed autofluorescence FLIM and, using various types of cancer and stem cell spheroids, is also presented.

The Effects of Temperature and Fluoroethylene Carbonate Concentration on the Formation of the Graphite SEI and Its Impact on the Full-Cell Performance

Extending the cycle-life of state-of-the-art lithium-ion batteries (LiBs) is, amongst other aspects, predicated on optimizing the properties of the solid electrolyte interphase (SEI), such as its stability and resistance.[1] It is formed at the negative electrode during the first cycles by electrolyte decomposition and acts as a passivating layer between the electrode surface and the electrolyte.[2,3] Since the SEI formation is accompanied by an irreversible loss of cyclable lithium, its stability during cycling is crucial for improving the charge/discharge efficiency of LiBs. Furthermore, the arising resistance associated with the SEI formation, predominantly depending on the SEI thickness, its chemical composition, and its lithium-ion conductivity, all impact the rate performance of the anode.[4] Two of the most crucial factors impacting SEI formation are temperature and electrolyte composition (i.e., using electrolyte additives).[5] Additives are added to the electrolyte to inhibit the predominant reduction of other electrolyte constituents and thereby form an SEI with improved stability during cycling.[1,6,7] One of the most prominent additives for LiBs is fluoroethylene carbonate (FEC), which is preferentially reduced compared to common carbonate solvents (e.g., ethylene carbonate, ethyl methyl carbonate) due to its higher reduction potential.[7] In this study, we investigated the influence of the formation temperature between 10 and 60 °C, as well as the concentration of FEC (2 and 20 %wt in EC:EMC 3:7 wt/wt with 1 M LiPF6, Gotion, USA) on the characteristics of a synthetic graphite (SMG-A5, Resonac, Japan) anode, both in SMG/Li half-cells and in Ni-rich NCM/SMG full cells.We quantified the first-cycle irreversible capacity loss (ICL) in SMG/Li half cells with a lithium reference electrode after two 0.1 C formation cycles and compared the FEC containing electrolytes to the baseline- (LP-57) and an LP-572 (1 M LiPF6 in EC:EMC 3:7 wt/wt + 2 %wt vinylene carbonate (VC), Gotion, USA) electrolyte. Employing electrochemical impedance spectroscopy in an SMG/Li half-cell setup with a µ-reference electrode and a free-standing graphite electrode,[8,9] we could further quantify the intercalation resistance (R Int, representing the sum of the charge-transfer and the SEI resistance) after an identical formation protocol at 40 % SOC. Both quantities, the ICL and R Int, increase with increasing formation temperature and higher FEC content.The impact of an increasing R Int on the rate performance was tested in Ni-rich NCM/SMG full cells with a lithium reference electrode, revealing a decreased rate capability and higher susceptibility for lithium plating for cells that were formed at higher temperatures and contained 20 %wt FEC. Additionally, the cycling stability of Ni-rich NCM/SMG full cells at 25 °C was assessed in coin cells. Despite an increased ICL and R Int after formation, cells that were formed at elevated temperatures and contained 20 %wt FEC showed enhanced cycling stability compared to those that were formed at a lower temperature and contained less FEC.Finally, on-line electrochemical mass spectrometry (OEMS) was employed to quantify the evolved gases during the formation of a Ni-rich NCM/SMG full cell containing either of the FEC-containing electrolytes at different temperatures. In accordance with an increased ICL and R Int, a higher formation temperature, as well as a higher FEC content, gave rise to a more pronounced gas evolution during formation.

Total Synthesis and Anti-inflammatory Activity of Asperjinone and Asperimide C.

Total syntheses of two γ-butenolide natural products, asperjinone (1) and asperimide C (2) in both racemic and chiral forms have been accomplished utilizing Basavaiah's one-pot Friedel-Crafts/maleic anhydride formation protocol as a key strategy. Our syntheses verified the revised structure of 1 proposed by Williams et al. and the structure and absolute configuration of 2 reported by the Li group. This work also discloses the unprecedented anti-inflammatory activity of 1. Synthetic 1 exhibited significant anti-inflammatory activity in renal proximal tubular epithelial cells (RPTEC) by suppression of gene expression of pro-inflammatory cytokines TNF-α, IL-1β and IL-6 under LPS-induced renal inflammation condition and was superior to (S)-1, rac-2, 2, and a positive drug control, indomethacin. Moreover, compound 1 inhibited downstream signaling of inflammation by significantly reducing iNOS and COX-2 gene expression and total NO production. The anti-inflammatory activity of asperjinone (1) renders it a potential and promising candidate for developing novel anti-inflammatory agents against inflammation worsening acute kidney injury.

Influence of Vinylene Carbonate and Fluoroethylene Carbonate on Open Circuit and Floating SoC Calendar Aging of Lithium-Ion Batteries

The purpose of this study was to investigate the calendar aging of lithium-ion batteries by using both open circuit and floating current measurements. Existing degradation studies usually focus on commercial cells. The initial electrolyte composition and formation protocol for these cells is often unknown. This study investigates the role of electrolyte additives, specifically, vinylene carbonate (VC) and fluoroethylene carbonate (FEC), in the aging process of lithium-ion batteries. The results showed that self-discharge plays a significant role in determining the severity of aging for cells without additives. Interestingly, the aging was less severe for the cells without additives as they deviated more from their original storage state of charge. It was also observed that the addition of VC and FEC had an effect on the formation and stability of the solid electrolyte interphase (SEI) layer on the surface of the carbonaceous anode. By gaining a better understanding of the aging processes and the effects of different electrolyte additives, we can improve the safety and durability of lithium-ion batteries, which is critical for their widespread adoption in various applications.

A Novel Method of Time-Varying Formation Control Based on a Directed Graph for Multiple Autonomous Underwater Vehicles

Currently, autonomous underwater vehicles (AUVs) are facing various challenges, rendering multiple-AUV (multi-AUV) formation control a pivotal research direction. The issues surrounding formation control for a multi-AUV system to establish time-varying formations must be investigated. This paper discusses the formation protocol of multi-AUV systems in order to establish the defined time-varying formations. First, when these systems establish formations, the speed of each AUV can be equivalent. After that, consensus-based methods are used to solve the time-varying formation-control problem. The necessary and sufficient process of multi-AUV in achieving time-varying formations is proved. Furthermore, the formula for the time-varying formation center function is provided. Further, we present a protocol law for multi-AUVs to establish time-varying formations. Finally, the theoretical results of a simulation are presented, which validate the formation protocol.

In vitro Apical Shoot Culture and Callus Formation of Durian (Durio zibethinus Murray)

Backgroud: Durian (Durio zibethinus Murray), A tropical fruit with high nutritional and commercial value, is widely cultivated in Southeast Asia. Unfortunately, growing durian is fraught with difficulties. Propagation is the traditional method for conserving plants. This method does have some drawbacks, one of which is that the original tree may suffer as a result. Therefore, a contemporary method for growing durian plants is plant tissue culture. Aim: The objective of this research is creating a premise for the development of durian high-value varieties by biotechnology, specifically setting up the first step closer to develop durian somatic cell formation protocol in vitro. Methodology: Effects of media MS on shoot culture and Kinetin and 2.4D on callus formation and growth. Experiments were designed by randomized complete block (RCB). Results: There are not significant difference between two treatments of 0.1 mg/L BAP (6-benzylaminopurine) added to 1/3xMS and free hormone medium, in an effort to preserve high-value durian varieties. There is research on formating callus from young leaves of durian affected by Kinetin and 2.4D. The outcomes demonstrated that MS medium supplemented with 3 mg/L 2.4D had an impact on the formation of callus on leaves. The combination of 1.0 mg/L Kinetin + 4.0 mg/L 2.4D make a significant to induce callus growth and callus area. Callus was white color, fresh and soft. Conclusion: the combination of Kinetin + 2.4D was finding the best combination to maintain the survival of callus induction and growth; coconut water treatment was highly effective in sustaining fresh callus.

Women’s Preferences for a Culinary Medicine Intervention to Reduce Cardiometabolic Risk During the Menopausal Transition: A Formative Study Protocol

Women’s Preferences for a Culinary Medicine Intervention to Reduce Cardiometabolic Risk During the Menopausal Transition: A Formative Study Protocol

Robust [formula omitted] time-varying formation control of singular multiagent systems under jointly connected topologies

This study investigates time-varying formation design and analysis problems for the singular multiagent systems (SMASs) with external disturbances and jointly connected topologies. Firstly, the novel nonlinear distributed formation protocol is formulated and the finite-time reachability of sliding mode surfaces is proved. Another improvement emphasizes that a common matrix can be extracted from the decomposition of all switching Laplacian matrices, which simplifies the formation control problem to admissible analysis. Secondly, by using the feedback impulse elimination and Cauchy convergence criterion methods, the solvability of the time-varying formation control is obtained. Thirdly, the external disturbances are well suppressed by the robust H∞ stability analysis. Finally, to verify the validity of the proposed theory, the simulation examples of hexagonal time-varying formation are provided.

Propagation of the Vanda helvola Orchid In Vitro

Orchids are more economical and tall than plants and other decorations. One of the orchids cultivated is the Vanda orchid. Seed orchid size is small and does not have endosperm, so it is not easy to germinate in nature, so tissue culture is one multiplication orchid in amount a lot and a short time. This study aims to know the growth of the seed orchid Vanda helvola on different media for 12 days after plant. Seed orchid V. helvola grown on modified Murashinge and Shoog (MS), modified Vaccin and Wend (VW) media and organic media. The research was conducted at the Tissue Culture Laboratory of the UPT Center for Food Crops and Horticulture (BBIPTH), Luwus Tanaban, from February to May 2023. The research method used was observation and experimentation, and the research design used RAK (group random design). Research shows modified MS Media, modified VW and organic capable change seeds orchid V. helvola. Modified MS and modified VW media can induce seed orchid V. helvola germination, and MS media can induce formation protocol.

Induced attack on formation control of multiagent systems with prescribed reference trajectories

AbstractThe induced attack on the formation control of multiagent systems is investigated from the perspective of the attacker, where a new induced attack strategy is proposed to drive the whole formation of multiagent systems to the prescribed reference trajectory. Compared with denial‐of‐service attacks and deception attacks, a desired formation reference trajectory with the stable formation structure is reached by the induced attack instead of disrupting the whole formation. First, the induced attack signal is produced by designing an attack generation exosystem, whose dynamics can be described by the regulated attack matrix and can be adjusted to generate the prescribed reference trajectory. Then, based on the local state information, the formation vector, and the induced attack signal among partial agents, a new distributed induced attack formation protocol is proposed, which is composed of the nominal formation term and the induced attack term. Meanwhile, the induced attack design criterion is proposed by utilizing a robust scheme, where the robust performance bound can be configured by two performance regulating parameters and can be used to design the appropriate regulated attack matrix. Furthermore, by establishing the projection of the induced attack signal onto the formation agreement subspace, an explicit expression of the prescribed reference trajectory is determined, which depicts the movement trajectory of the entire formation of the multiagent system under the induced attack. Finally, a simulation is provided to vindicate the effectiveness of theoretical results.

Relating Chemo-Mechanical Hysteresis and Formation Protocols for Anode-Free Lithium Metal Batteries

Cell formation is an energy and time-intensive empirically-guided process crucial to manufacturing secondary lithium-ion batteries. As the rechargeable battery industry moves towards manufacturing lithium metal batteries—where a metallic lithium negative electrode is used instead of a porous graphite composite—the cell formation process may need reconsidering. The effects of formation rate and cycling protocol on lithium metal battery performance are poorly understood. In this work, we used operando acoustic transmission to measure physical changes during the formation cycles and the effect of formation cycling protocols on the long-term cycling of anode-free lithium metal pouch cells—where all the lithium inventory comes from the positive electrode and is deposited as metallic lithium on copper foil during initial charge. We show that a faster C/3 formation protocol results in comparable cycling performance and cell stiffness change to a slower C/10 formation step. Variations in acoustic metrics across different electrolytes tested are attributed to differences in gas formation, cell swelling, and lithium deposition morphology. NMC811 cathodes paired with a high-concentration ether electrolyte are shown to be particularly prone to gas formation, which is mitigated by using a localized high-concentration ether electrolyte and single-crystal NMC532. The results highlight differences in formation behavior between anode-free lithium metal cells and lithium-ion cells. These are important to consider when bringing new manufacturing plants online for lithium metal batteries.