Optimal Function Research Articles

Induction of Alkaline Bands in Chara by External Electric Current Reveals the Influence of Plasma Membrane H+ Fluxes on Cyclosis-Mediated Signaling

Long-distant communications in plants and giant plant cells are essential for optimal cell functioning under variable environmental conditions. In characean internodal cells exposed to spotted or flickering light, the redox balance in dimly lit chloroplasts is sensitive to the reducing power produced in brightly illuminated chloroplasts of a distal cell region located upstream in the directed cytoplasmic flow. The distant communication is mediated by excessive production in the high-light region of reducing metabolites that are exported into the streaming cytoplasm and delivered by cytoplasmic flow to light-starving chloroplasts. These target chloroplasts perceive the transportable metabolic signal, which is reflected in the transient increase of modulated chlorophyll fluorescence F '. Previous studies of cyclosis-mediated F ' transients revealed that they are sensitive to natural H+ fluxes across the plasma membrane and that the signal transduction is suppressed in cell areas with massive H+ influx. In this study with Chara australis R. Br., we show that the injection of inward electric current is accompanied by proton influx sufficient for the creation of artificial alkaline band. The combined application of PAM chlorophyll microfluorometry, local light stimuli, and measurements of pericellular pH showed that the microfluidic signal transduction is notably suppressed under artificially produced alkaline band where H+ influx acidifies the cytoplasm. It is hypothesized that changes in cytoplasmic pH regulate the rates of electron flows directed to NADP reduction and O2 reduction, which may disturb long-distance redox control system involving production and consumption of reducing equivalents.

Structural and functional optimization of glycoprotein-enzymes for targeted biocatalysis in oral squamous cell carcinoma

The efficacy of optimized glycoproteinenzymes as a novel therapeutic approach for oral squamous cell carcinoma (OSCC) was tested in this study. The stability and viability of SCC-25 and HN4 operating-system cell lines were characterized. Both lines were confirmed to have a spindle-like morphology for SCC-25, while HN4 cells exhibited cobblestone-like clusters. Viability decreased with time for cell clones SCC-25 was 95 % and 80 % after five days, while HN4 was 94 % and 79 %. Enzyme 1, expression in E. coli and Pichia pastoris to high purity recombinant glycoprotein-enzymes. Activities of these enzymes varied equally among experimental conditions. The enzyme showed an activity of 18 units at Condition D as active max, Enzyme 2 retraced 16 units, and Enzyme 3 reached this point in the same condition. Differences in activity between different conditions were also found in various experimental conditions. In therapeutic assessments, glycoprotein-enzyme treatment lowered OSCC cell viability with IC50 values of 10–15 g/ml. Successful cellular localization could be detected primarily in the cytoplasm and nucleus of live animal tissue following treatment with those therapies. In preclinical xenograft models, treatment resulted in a 40–50 % reduction in tumour volume and growth rates, with treated tumours displaying a 60 % decrease in Ki-67, a 50 % reduction in Bcl-2, and a 70 % increase in cleaved caspase-3. Additionally, the Bax/Bcl-2 ratio increased by 80 %, and CD31 staining revealed a 40 % reduction in microvessel density. These results suggest that optimized glycoprotein enzyme therapy effectively inhibits tumour growth, induces apoptosis and reduces angiogenesis, thus laying a solid foundation for its application in clinical therapy of OSCC.

Optimization of A Dynamic Program for Water Resources Utilization in the Mambal Irrigation Area

The Irrigation Area (D. I.) Mambal, which passes through Badung Regency, Denpasar City, and Tabanan Regency, is the largest irrigation water supplied by the Ayung River, covering an area of 5.963 Ha. Despite the Ayung River’s substantial water potential, the D. I. Mambal experiences water shortages during certain months. This research aims to improve the effectiveness and efficiency of irrigation water use based on the Global Planting Management Plan (RTTG) using simulation methods and dynamic program optimization. Simulations were carried out under low conditions, normal and sufficient dependable discharges, using both existing and alternative RTTG. The objective function of the dynamic optimization seeks to maximize revenue gain from the applied RTTG. The existing cropping pattern at the beginning of planting in October showed an average proportion of fulfillment of water irrigation needs at 85%. Under the Alternative I condition, with planting beginning in November, the average proportion of fulfillment of irrigation water needs was 89%. In Alternative II conditions, with planting beginning in December, the average proportion of fulfillment of irrigation water needs was 87%. By optimizing the water discharge using the dynamic program, the irrigation profit for the existing cropping pattern (October) amounted to IDR 491,816,154,938. The highest profit was obtained using the Alternative II cropping pattern (December), totaling IDR 606,675,369,830. Meanwhile, the lowest profit was obtained in the Alternative I cropping pattern (November), which was IDR 360,767,292,361. The analysis showed that the Alternative II cropping pattern, starting with the first rice planting period in December, yields the most optimal results. The analysis considers the optimized air allocation and irrigation benefits obtained from the third cropping pattern.

Chicken ANP32A-independent replication of highly pathogenic avian influenza viruses potentially leads to mammalian adaptation-related amino acid substitutions in viral PB2 and PA proteins.

Acidic nuclear phosphoprotein 32 family member A (ANP32A) is an important host factor that supports the efficient replication of avian influenza viruses (AIVs). To develop an antiviral strategy against Gs/Gd-lineage H5 highly pathogenic avian influenza (HPAI) viruses in chickens, we established chicken ANP32-knockout (chANP32A-KO) DF-1 cells and evaluated their antiviral efficacy through in vitro validation. The replication of all HPAI viruses tested in chANP32A-KO cells was significantly lower compared to that of wild-type DF-1 cells. However, when HPAI strains A/mountain hawk-eagle/Kumamoto/1/2007 (H5N1; MHE) and A/chicken/Aichi/2/2011 (H5N1; H5Aichi) were passed in chANP32A-KO cells, mutant viruses were generated, which exhibited comparable replication levels in both chANP32A-KO and wild-type DF-1 cells. Sequence analysis revealed that mammalian-adaptive amino acid mutations PB2_D256G and PA_T97I were present in the MHE mutant virus, and the PB2_E627K mutation was identified in the H5Aichi mutant virus. These mutations have also been reported to enhance the polymerase activity of AIVs in mammalian cells; however, the minigenome assay in the present study showed that the polymerase activity of mutant viruses in chANP32A-KO cells was not restored to levels comparable to those in wild-type DF-1 cells. These findings suggest that ANP32A-independent viral replication may induce amino acid substitutions associated with mammalian adaptation in AIVs. They also imply that the high efficiency of viral replication mediated by these amino acid mutations may not result from enhanced polymerase activity but rather involve other undefined mechanisms.IMPORTANCEDuring the host-switching of avian influenza viruses (AIVs) to mammalian hosts, introducing adaptive mutations into viral proteins is essential to ensure optimal functionality through virus-host protein interactions in mammalian cells. However, the mechanisms leading to adaptive mutations in viral proteins remain unclear. Among several host proteins that promote viral growth, acidic nuclear phosphoprotein 32 family member A (ANP32A) is known to be an important factor for efficient viral replication. Here, we generated mutant highly pathogenic avian influenza viruses capable of ANP32A-independent replication in a chicken-derived cell line. We demonstrated that several amino acid mutations found in the mutant viruses correspond to those associated with the mammalian adaptation of AIVs. These results suggest that ANP32A-independent viral replication is one of the mechanisms for introducing amino acid mutations that are reportedly involved in the mammalian adaptation of AIVs.

Innovation Through the Titip Bandaku Program at Library and Archives Services of Klaten Regency, Indonesia

Background: Concerning archival services, local government agencies are responsible for managing archives within the regions. The Klaten Regency Government has adopted technology to produce innovation in public archives services, focusing on the management and preservation of archival records. To achieve this objective, the Titip Bandaku (Titip Berkas Arsip Digitalku) archival innovation program was established, facilitating the digital conversion of physical documents. However, in the implementation of program which has been running for approximately 5 years, the volume of digitized documents has not met the targets set by Library and Archives Services as the implementing government agency. Purpose: Therefore, This study aimed to examine the implementation of the Titip Bandaku program in protecting and preserving archives, identifying the obstacles included, and how the Klaten Regency Library and Archives Services addressed these challenges. Method: A qualitative-descriptive method was used to describe the implementation of the Titip Bandaku innovation based on the theory of innovation (State Administration Institute, 2017) with two dimensions of innovation namely output and outcome5. Data collection methods included observation, interviews, and documentation. The collected data further underwent stages of analysis through data collection, reduction, presentation, and conclusion. Result: The implementation of the Titip Bandaku Innovation Program positively impacted the preservation of community archives against disasters by digitizing records. On the Output indicator, program was a pioneering effort within Klaten Regency to protect archives in disaster-prone areas, offering swift and customized services despite capacity limitations. On the Outcome indicator, program improves the security of community archives, lowers transportation costs through a mobile services system, and shows sustainability with the backing of regulations, funding, and continuous enhancement of facilities and services. Conclusion: The Titip Bandaku program at the Klaten Regency Library and Archives Services did not achieve optimal functionality. Factors hindering progress included limited human resources, inadequate facilities and infrastructure, and the poor condition of some archives. To improve program’s effectiveness, several measures were recommended, such as forming a dedicated Titip Bandaku team, increasing public outreach through community activities, and fostering partnerships with relevant stakeholders.

Optimization Function for Determining Optimal Dose Range for Beef and Seed Potato Irradiation

Optimization Function for Determining Optimal Dose Range for Beef and Seed Potato Irradiation

200 mm optical synthetic aperture imaging over 120 meters distance via macroscopic Fourier ptychography

Fourier ptychography (FP) imaging, drawing on the idea of synthetic aperture, has been demonstrated as a potential approach for remote sub-diffraction-limited imaging. Nevertheless, the farthest imaging distance is still limited to around 10 m, even though there has been a significant improvement in macroscopic FP. The most severe issue in increasing the imaging distance is the field of view (FoV) limitation caused by far-field conditions for diffraction. Here, we propose to modify the Fourier far-field condition for rough reflective objects, aiming to overcome the small FoV limitation by using a divergent beam to illuminate objects. A joint optimization of pupil function and target image is utilized to attain the aberration-free image while estimating the pupil function simultaneously. Benefiting from the optimized reconstruction algorithm, which effectively expands the camera’s effective aperture, we experimentally implement several FP systems suited for imaging distances of 12 m, 65 m, and 120 m with the maximum synthetic aperture of 200 mm. The maximum synthetic aperture is thus improved by more than one order of magnitude of the state-of-the-art works from the furthest distance, with an over fourfold improvement in the resolution compared to a single aperture. Our findings demonstrate significant potential for advancing the field of macroscopic FP, propelling it into a new stage of development.

Choroidal macrophages in homeostasis, aging and age-related macular degeneration

With increasing age, the optimal functioning of the choroid is essential for efficient removal of waste products formed from photoreceptor renewal. A decline in regulatory elements of the immune system, termed immunosenescence, and the failure of para-inflammation to restore tissue homeostasis can result in the progression of healthy aging to sight-threatening inflammation of the choroid. Macrophages are uniquely situated between the innate and adaptive immune systems, with a high capacity for phagocytosis, recognition of complement components, as well as antigen presentation. In this review, we provide an overview of macrophages and their properties in the healthy choroid and cover the impact of aging, immunosenescence and inflammaging on the function of choroidal macrophages. We will discuss the impact of age on macrophage phenotype and behaviour in the pathophysiology of age-related macular degeneration.

Human-Machine Function Allocation Method for Submersible Fault Detection Tasks

The operation and support (OS) officer is responsible for buoyancy regulation and fault detection of onboard equipment in the civil submersible. The OS officer carries out the above tasks through the human-machine interface (HMI) of a submersible buoyancy regulation and support (SBRS) system. However, the OS officer often faces uneven task frequency produced by fault tasks, which leads to an unbalanced mental workload and individual failures. To address this issue, we proposed a human-machine function allocation method based on level of automation (LOA) taxonomy and submersible task complexity (STC), aimed at improving human-machine cooperation in submersible fault detection tasks. Based on this method, we identified the LOA2 as the optimal human-computer function allocation scheme. In this study, three measurement techniques (subjective scale, work performance, and physiological status) were used to test 15 subjects to validate the effectiveness of the proposed optimal human-machine function allocation scheme. The GAMM test results also indicate that the proposed optimal human-machine function allocation scheme (LOA2) can improve the work performance of the operating system officials under low or high workloads and reduce the subjective workload.

Localization of hidden leaks in water supply networks by hydraulic methods

AbstractThe hydraulic gradient method is an effective approach for localizing hidden leaks in water supply networks. Relative errors in leakage location depend significantly on head measurement errors, necessitating the use of high-precision pressure gauges with an accuracy class of 0.25 or better. An optimization function, defined as the ratio of the localization relative error to the probability of detection, was used to determine the optimal location for the control section. Dependencies of localization relative error on the pressure gauge accuracy class, section length, and piezometric head are obtained. Presented multi-leakage estimation model enables the assessment of the multi-leakage probability, enhancing decision-making efficiency for emergency repairs in water supply networks.

Optimal private payoff manipulation against commitment in extensive-form games

Stackelberg equilibrium describes the optimal strategies of a player, when she (the leader) first credibly commits to a strategy. Her opponent (the follower) will best respond to her commitment. To compute the optimal commitment, a leader must learn enough follower's payoff information. The follower can then potentially provide fake information, to induce a different final game outcome that benefits him more than when he truthfully behaves.We study such follower's manipulation in extensive-form games. For all four settings considered, we characterize all the inducible game outcomes. We show the polynomial-time tractability of finding the optimal payoff function to misreport. We compare the follower's optimal attainable utilities among different settings, with the true game fixed. In particular, one comparison shows that the follower gets no less when the leader's strategy space expands from pure strategies to behavioral strategies. Our work completely resolves this follower's optimal manipulation problem on extensive-form game trees.

Event-triggered adaptive dynamic programming for cable-driven parallel rehabilitation system with uncertainties

An event triggered adaptive dynamic programming (ET-ADP) controller is proposed for the cable-driven parallel rehabilitation system (CDPRS). Firstly, an error dynamics of CDPRS considering composite uncertainty is established. Secondly, to reduce the computational burden, a single critic network ADP method is proposed to obtain the approximate optimal cost function, and an event-triggered mechanism is introduced to save the communication resources simultaneously. Thirdly, considering the unidirectional force characteristics of the cables, the null-space reallocation method is adopted to optimise the tension of the cables. Then, based on Lyapunov stability theory, the uniformly ultimately boundedness (UUB) of the closed-loop system is proved. Finally, effectiveness of the proposed optimal tracking control strategy is verified based on the Matlab/simulink platform.

Numerical Solutions to the Variational Problems by Dijkstra’s Path-Finding Algorithm

In this work, we propose the general idea of using a path-finding algorithm to solve a variational problem. By interpreting a variational problem of finding the function that minimizes a functional integral as a shortest path finding, we can apply the shortest path-finding algorithm to numerically estimate the optimal function. This can be achieved by discretizing the continuous domain of the variational problem into a spatially weighted graph. The weight of each edge is defined according to the function of the original problem. We adopt the Moser lattice as the discretization scheme since it provides adjustable connections around a vertex. We find that this number of connections is crucial to the estimation of an accurate optimal path. Dijkstra’s shortest path-finding algorithm was chosen due to its simplicity and convenience in implementation. We validate our proposal by applying Dijkstra’s path-finding algorithm to numerically solve three famous variational problems, i.e., the optical ray tracing, the brachistochrone, and the catenary problems. The first two are examples of problems with no constraint. The standard Dijkstra’s algorithm can be directly applied. The third problem is an example of a problem with an isoperimetric constraint. We apply the Lagrangian relaxation technique to relax the optimization in the standard Dijkstra algorithm to incorporate the constraint. In all cases, when the number of sublattices is large enough, the results agree well with the analytic solutions. In all cases, the same path-finding code is used, regardless of the problem details. Our approaches provide more insight and promise to be more flexible than conventional numerical methods. We expect that our method can be useful in practice when an investigation of the optimal path in a complex problem is needed.

Reticular Chemistry for Enhancing Bioentity Stability and Functional Performance.

Addressing the fragility of bioentities that results in instability and compromised performance during storage and applications, reticular chemistry, specifically through metal-organic frameworks (MOFs) and covalent organic frameworks (COFs), offers versatile platforms for stabilization and enhancement of bioentities. These highly porous frameworks facilitate efficient loading and mass transfer, offer confined environments and selective permeability for stabilization and protection, and enable finely tunable biointerfacial interactions and microenvironments for function optimization, significantly broadening the applications of various bioentities, including enzymes, nucleic acids, cells, etc. This Perspective outlines strategies for integrating bioentities with reticular frameworks, highlighting new design ideas for existing issues within these strategies. It emphasizes the crucial roles of these frameworks for bioentities in enhancing stability, boosting activity, imparting non-native functions, and synergizing bioentity systems. Concluding with a discussion of the challenges and prospects in the design, characterization, and practical applications of these biocomposites, this Perspective aims to inspire further development of high-performance biocomposites in this promising field.

IMPLEMENTATION OF OPTIMAL RECONFIGURATION OF UAV SWARM

Now the use of copter-type UAVs in various sectors of the economy is economically justified and sometimes has no alternative. The next step toincrease the efficiency of such technology is the use of groups of UAVs united by a single task. If such groups contain a large number of deviceslocated quite densely, they are called swarms. A clear, well-known example of the use of swarms of quadcopters is the creation of visual images in thesky and their transformation according to a certain program. Obviously, the possibilities of such structures are much wider and they have very goodprospects in the future. But in order to realize such opportunities, it is necessary to solve a number of problems, starting with methods of obtaining andexchanging current information between group members, ending with strategic planning and operational management of individual devices. Thesetasks are burdened by additional conditions of safety and optimal functioning. This article considers the modeling of the optimal reconfiguration of alarge group of UAVs from the actual initial state to the desired final state. For each device, the final point to which it will move is determined. Such aproblem does not have a unique solution, therefore an optimality criterion was added – the duration of complete reconfiguration, which must beminimized. The task is considered under conditions of the same and constant flight speed of all copter-type UAVs. Analysis of all options isimpossible, because the computational complexity of such a method is proportional to the N factorial, where N is the number of UAVs in the group. Aquasi-optimal method has been developed, the complexity of which is proportional to N. Statistical modeling has proven its effectiveness, which canbe compared with the effectiveness of the optimal method. Indirect estimates of its effectiveness in the general case were also obtained. Specificexamples of swarm reconfiguration are considered. The algorithm for preventing collisions of UAVs while moving along designated trajectories isdescribed and studied. The obtained results are an integral part of the set of tasks for navigation and control of UAVs in the conditions of a large densegroup.

Bioprinting a resilient and transparent cornea stroma equivalent: harnessing dual crosslinking strategy with decellularized cornea matrix and silk fibroin hybrid.

Bioprinting a resilient yet optically transparent corneal tissue substitute remains a challenge. In this study we introduce an innovative methodology aimed at bolstering the mechanical and optical attributes of silk fibroin (SF) hydrogels, pivotal for the progression of cornea tissue engineering. We devised a unique eosin Y-based photoinitiator system to instigate di-tyrosine linkages within highly concentrated pristine SF solutions under green light exposure. This pioneering technique resulted in SF hydrogels fortified by dityrosine covalent bonds, preserving exceptional transparency and soft elastomeric qualities devoid of spontaneous transitions to stiff, opaque beta-sheet conformations. Furthermore, we synergistically combined SF with decellularized corneal matrix (DCM) hydrogel, leveraging photo-polymerization under green light followed by thermal gelation to establish resilient and stable gel formation. The ensuing dual crosslinked hybrid hydrogels exhibited superior mechanical and thermal resilience in comparison to dual crosslinked DCM hydrogels. The inclusion of SF in DCM further augmented the hydrogel's elasticity and shear recovery, positioning it as an optimal bioink for cornea bioprinting endeavors. During the extrusion printing process, photocrosslinking of the bioink superficially fortified SF and DCM polymer chains via di-tyrosine linkages, furnishing initial stability and mechanical fortitude. Subsequent post-printing thermal gelation further reinforced collagen chains through self-assembly. Notably, the bioprinted cornea constructs, housing human limbal mesenchymal stem cells (hLMSCs), manifested transparency, structural integrity, and optimal functionality, underscored by the expression of keratocyte proteoglycans. In summation, our engineered 3D constructs exhibit promising potential for in vivo applications in cornea tissue engineering, marking a significant stride forward in the field's advancement.

Physical constraints on the positions and dimensions of the zebrafish swim bladder by surrounding bones

AbstractPrecise regulation of organ size and position is crucial for optimal organ function. Since the swim bladder is primarily responsible for buoyancy in teleosts, early development and subsequent inflation of the swim bladder should be appropriately controlled with the body growth. However, the underlying mechanism remains unclear. In this study, we show that the size and position of the swim bladder are physically constrained by the surrounding bones in zebrafish. Non‐invasive micro‐CT scanning revealed that the anterior edge of the swim bladder is largely attached to the os suspensorium, which is an ossicle extending medioventrally from the 4th centrum. Additionally, we observed that hoxc6a mutants, which lack the os suspensorium, exhibited an anterior projection of the swim bladder beyond the 4th vertebra. During the swim bladder development, we found that the counterclockwise rotation of the os suspensorium correlates with posterior regression of the swim bladder, suggesting that the os suspensorium pushes the swim bladder posteriorly into its proper position. Furthermore, our results revealed a close association between the posterior region of the swim bladder and the pleural ribs. In hoxaa cluster mutants with additional ribs, the swim bladder expanded posteriorly, accompanied by an enlarged body cavity. Taken together, our results demonstrate the importance of the surrounding bones in the robust regulation of swim bladder size and position in zebrafish.

Solving the Control Synthesis Problem Through Supervised Machine Learning of Symbolic Regression

This paper considers the control synthesis problem and its solution using symbolic regression. Symbolic regression methods, which were previously called genetic programming methods, allow one to use a computer to find not only the parameters of a given regression function but also its structure. Unlike other works on solving the control synthesis problem using symbolic regression, the novelty of this paper is that for the first time this work employs a training dataset to address the problem of general control synthesis. Initially, the optimal control problem is solved from each point in a given set of initial states, resulting in a collection of control functions expressed as functions of time. A reference model is then integrated into the control object model, which generates optimal motion trajectories using the derived optimal control functions. The control synthesis problem is framed as an approximation task for all optimal trajectories, where the control function is sought as a function of the deviation of the object from the specified terminal state. The optimization criterion for solving the synthesis problem is the accuracy of the object’s movement along the optimal trajectory. The paper includes an example of solving the control synthesis problem for a mobile robot using a supervised machine learning method. A relatively new method of symbolic regression, the method of variational complete binary genetic programming, is studied and proposed for the solution of the control synthesis problem.

Struwe’s global compactness and energy approximation of the critical Sobolev embedding in the Heisenberg group

Abstract We investigate some of the effects of the lack of compactness in the critical Folland–Stein–Sobolev embedding in very general (possible non-smooth) domains, by proving via De Giorgi’s Γ-convergence techniques that optimal functions for a natural subcritical approximations of the Sobolev quotient concentrate energy at one point. In the second part of the paper, we try to restore the compactness by extending the celebrated Global Compactness result to the Heisenberg group via a completely different approach with respect to the original one by Struwe [M. Struwe, A global compactness result for elliptic boundary value problems involving limiting nonlinearities, Math. Z. 187 1984, 4, 511–517].

Isolation, Characterization, and Genome Engineering of a Lytic Pseudomonas aeruginosa Phage.

Antibiotic-resistant bacterial infections have become one of the leading causes of human mortality. Bacteriophages presented great potential for combating antibiotic-resistant infections in the post-antibiotic era due to their high host specificity and safety profile. Pseudomonas aeruginosa, an opportunistic pathogenic bacterium, has shown a surge in multidrug-resistant strains, severely impacting both human health and livestock. In this study, we successfully isolated and purified a P. aeruginosa-specific phage, PpY1, from feces collected from a breeding farm. This phage harbors a short tail and a 43,787 bp linear genome, and exhibited potent lytic activity against several pathogenic P. aeruginosa strains. Leveraging Transformation-associated recombination (TAR) cloning and phage assembly techniques in a P. aeruginosa host lacking a restriction-modification system, we developed a genome engineering platform for PpY1. Through a systematic gene knockout approach, we identified and eliminated 21 nonessential genes from the PpY1 genome, resulting in a series of phages with reduced genomes. This research not only enhances our understanding of the phage genome but also paves the way for the functional optimization of phages, e.g., broadening the host spectrum and elevating the lytic capacity, dedicated towards the treatment of bacterial infections.