Biological Control Systems Research Articles

Blowfly yaw control via electrical stimulation of the H1 lobula plate tangential cell.

Eliciting predictable flight responses in insects via exogenous stimulation of the nervous system is an area of both scientific and engineering interest. Blowflies in particular possess an excellent biological flight control system, making them an ideal system for characterising responses to stimulation. Here we demonstrate a means of electrically controlling Calliphoridae-Protophormia terranovae wing behaviour, generating a repeatable yaw response via biphasic electrical stimulation of the H1 lobula plate tangential cell (LPTC). We found that a 10 mA current pulse at a frequency of 30-270 Hz produces a yaw response in the preferred direction of H1 in a tethered blowfly preparation, and the magnitude of the yaw response is proportional to the frequency of the stimulus. This result suggests that these LPTCs, which encode optic flow, may be a viable interface for controlling fly flight behaviour. This platform could find application not only for micro air vehicles (MAVs), but also in developing flight models or for studying neurological control of fly flight behaviour.

Design Constraints for Biological Systems That Achieve Adaptation and Disturbance Rejection

Many processes in natural biological systems, such as chemotaxis in bacteria and osmoregulation in yeast, rely on control architectures fundamentally equivalent to commonly used motifs from electrical and control engineering. However, difficulties arise when designing and implementing these architectures in a biological context due to uncertainties inherent in the behavior of biological systems and physical limitations of the available parts. In this paper, we discuss recent developments in the study of biological control systems, which are increasingly necessary for realization of complex synthetic biological constructs, focusing on methods for their design and implementation. We establish a range of desirable properties that ease implementation of biological constructs and apply classical control theory to derive a set of constraints to aid the design of systems that achieve adaptation or disturbance rejection. We demonstrate how these constraints can be used in practice, first deriving the necessary structure for a linear system that achieves adaptation, and then embedding this in a nonlinear model of biological relevance that could be built in the laboratory.

Dynamic control of arabinose and xylose utilization inE. coli

AbstractThe common bacteriumEscherichia coli(E. coli) can utilize the pentose sugars arabinose and xylose for growth and energy. When fed both these sugars, the bacterium preferentially utilizes arabinose and only when all the arabinose is exhausted from the media does it start to use xylose. This hierarchical utilization of the two sugars is dictated by two proteins: AraC and XylR. These proteins act as controllers of sugar utilization and dictate the timing and rate of utilization of these sugars. While the biochemical interactions defining individual arabinose and xylose utilization systems are well understood, it is not completely understood how the hierarchical utilization is maintained by the bacterium, and how the regulatory crosstalk between the two systems facilitates this hierarchy. To help answer these questions, in this work, we systematically experimentally characterize the regulatory crosstalk between the two sugar utilization systems.Our work demonstrates extensive interaction between the two sugar systems. Specifically, data from our experiments suggest that the xylose system can regulate arabinose gene expression and consequently, cellular physiology dynamically via promiscuous transport and maybe through cross interactions between regulator and non‐cognate sugar. Put together, we demonstrate that arabinose and xylose utilization networks exhibit an example of distributed control in a biological system. This design likely ensures that the system does not fail under perturbations (mutations). Our results help understand multi‐process control in biological systems and bring to light design criteria for synthetic biology applications.

GC-MS analysis of Eclipta prostrata leaf extracts in relation to larvicidal activity against the mosquito Aedes aegypti

The mosquito is the principal vector of many of the vector borne diseases affecting human beings and animals. Several mosquito species vectors for the pathogens of various diseases like malaria, filariasis, Japanese encephalitis, dengue fever, dengue haemorrhagic fever and yellow fever. Repeated use of synthetic insecticides for mosquito control has disrupted natural biological control systems and led to resurgences in mosquito populations. It has also resulted in the development of resistance, undesirable effects on non-target organisms and fostered environmental and human health concern, which initiated a search for alternative control measures. Plants are considered as a rich source of bioactive chemicals and they may be an alternative source of mosquito control agents. They even result in mutation of genes and these changes become prominent only after a few generations. Hence, the present study has been choosen to determine the photochemical screening, compound identification by GC-MS studyand larvicidal activity in various concentratingof Eclipta prostrata leaves extractagainst Aedes aegypti. The phytochemicals such as saponins, tannins, phenols, terpenoids, flavanoids, amino acids and protein, carbohydrates, glycosides were identified in both aqueous and methanol extracts, further revealed that Eclipta prostrata extract exhibited significantly highest larvicidal activity in 400 ppm at 24 hrs of methanol extract when compared to aqueous extract. The GC-MS analysis, showed 16 different compoundsand the compound isopropyl myristate, is found to be present in high area percentage.Further, the result of the currentinvestigation revealed that the methanol extract of Eclipta prostrata possess good larvicidal activity against Aedes aegypti with maximum larvicidal repellent and the numbers of the dead larvae were affected by increasing the concentrations of the plant extracts.

Identifying central and peripheral nerve fibres with an artificial intelligence approach

Distinguishing axons from central or peripheral nervous systems (CNS or PNS, respectively) is often a complicated task. The main objective of this work was to facilitate and support the process of automatically distinguishing the different types of nerve fibres by analysing their morphological characteristics. Our approach was based on a multi-level hierarchical classifier architecture that can handle the complexity of directly identifying nerve-fibre groups belonging to either the CNS or the PNS. The approach adopted comprises supervised methods (multilayer perceptron and decision trees), which are responsible for distinguishing the origin of the axons (CNS or PNS), whereas the unsupervised method (K-means clustering) performs nerve fibre clustering based on similar characteristics for both the CNS and PNS. Our experiments produced results with an accuracy higher than 88%. Our findings suggest that the development and implementation of a multi-level system improves automation capabilities and increases accuracy in the classification of nerves. Furthermore, our architecture allows for generalisation and flexibility, which can subsequently be extended to other biological control systems.

Synthetic Biology for Teaching Control Engineering: A Case Study in a Student-Directed, Collaborative Environment

Abstract –As the bio-based economy expands, Chemical Engineering graduates will find themselves in new contexts for which they must be prepared. The broad shift toward including biology in departmental research and teaching activities reflects this, but relatively little formal thought has been given to the pedagogy of biology within Chemical Engineering curricula. The case study presented here is centered on the use of a biological control system in a lab setting as the means by which advanced control concepts can be taught to upper-year and graduate students within a constructivist framework. This approach was successfully applied to achieve all of the learning outcomes for the lab, but student feedback indicated that structured collaboration and metacognitive activities should have been given higher priority to improve student experiences. A re-iteration of this framework for upper-year lab curriculum design based on student feedback is presented.

The perceptual shaping of anticipatory actions.

Humans display anticipatory motor responses to minimize the adverse effects of predictable perturbations. A widely accepted explanation for this behaviour relies on the notion of an inverse model that, learning from motor errors, anticipates corrective responses. Here, we propose and validate the alternative hypothesis that anticipatory control can be realized through a cascade of purely sensory predictions that drive the motor system, reflecting the causal sequence of the perceptual events preceding the error. We compare both hypotheses in a simulated anticipatory postural adjustment task. We observe that adaptation in the sensory domain, but not in the motor one, supports the robust and generalizable anticipatory control characteristic of biological systems. Our proposal unites the neurobiology of the cerebellum with the theory of active inference and provides a concrete implementation of its core tenets with great relevance both to our understanding of biological control systems and, possibly, to their emulation in complex artefacts.

Role and underlying mechanisms of the interstitial protein periostin in the diagnosis and treatment of malignant tumors (Review)

Invasion and metastasis are the major characteristics of malignant tumors and are complex processes involving multiple genes. Gene regulation is a precise, large and complex biological control system, and its underlying mechanisms remain to be elucidated. Mesenchymal-specific genes are expressed primarily by mesenchymal cells, and the expression products of these genes are molecules with various structures and functions, including secreted proteins and extracellular matrix proteins. The periostin gene has been newly identified as a mesenchymal-specific gene and an extracellular-matrix secreted protein. Periostin is able to bind to various subtypes of integrin receptors on the surface of the cell membrane. This triggers relevant signal transduction pathways to alter the microenvironment of cancer cells in order to facilitate their survival, invasion, metastasis and angiogenesis as well as enhance the tolerance to hypoxia and chemicals. Therefore, periostin is associated with the grade of malignancy, level of invasion and prognosis of malignant tumors. The in-depth study of periostin may provide an effective marker for tumor diagnosis and prognosis, as well as a novel treatment target.

Підвищення рівня підготовленості кваліфікованих баскетболістів у підготовчому періоді

Purpose : to study the adaptation of basketball players of student teams to training loads during the preparatory period of the annual cycle of training on the parameters of motor qualities and functional readiness . Material & Methods : conducted a survey of 12 basketball players on the team (Sumy, the highest league of the Ukrainian Basketball Championship ). The following research methods were used: theoretical analysis of literary sources, methods of mathematical statistics, anthropometry and pedagogical control . Result : dynamics of changes at the stage of preparation for the season is shown . It is established and observed that under the influence of training sessions in the examined basketball players, not only the optimization of the functional systems of their organism, but also the level of the functional state of the organism as a whole . Conclusion : assessment of the functional condition of the athlete's body should play an important role in the overall system of medical and biological control in connection with significant additional information on the state of their body and the possibility of timely correction of physical activity and the provision of preventive measures . It is determined that during the preparatory period the level of motor qualities and functional readiness of the basketball players increased .

Feedback Control and Synthetic Biology: Constraints on Design

Synthetic Biology is an emerging field at the interface of biology and engineering, concerned with the design and implementation of synthetic biological parts, devices and systems. With applications ranging from industrial biosynthesis of chemicals to treatment and prevention of disease, Synthetic Biology holds great promise, but faces several challenges due to the uncertainties and noise inherent in biological systems. In this paper we review recent progress in the design and testing of biological control systems that aim to overcome these limitations. We then use classical control theory to derive a number of design constraints for implementation of linear control systems that achieve adaptation and disturbance rejection. Finally, we design a linear system for rejection of ramp-type disturbances, and from this demonstrate how the derived linear system constraints can be embedded in a more realistic non-linear biological context.

Laboratory evaluation of the effect of Beauveria bassiana on the predatory mite Phytoseiulus persimilis (Acari: Phytoseiidae).

Tetranychus urticae Koch (Acari: Tetranychidae), a major pest of many agricultural crops, is mainly controlled with chemical acaricides. However, predatory mites and entomopathogens have been proposed as alternative control agents. In this study, the effect of the BotaniGard® GHA strain of Beauveria bassiana on the survival, longevity, fecundity, and egg hatch rate of the predatory mite Phytoseiulus persimilis Athias-Henriot (Acari: Phytoseiidae) were studied under laboratory conditions. When B. bassiana was applied directly to P. persimilis eggs at a concentration of 1×108conidia/ml, corrected hatchability was less than 5%, and the corrected mortality of nymphs and adults was not significantly different from control 10days after treatment. Phytoseiulus persimilis nymphs that hatched from treated eggs showed no significant change in their development time, adult female longevity, hatch rate, survival rates over time, or offspring sex ratio. However, significant negative effects on fecundity and life table parameters (net reproductive rate, intrinsic rate of natural increase, mean generation time, finite rate of increase, and doubling time) were found when B. bassiana was applied to the adult stage. Spraying B. bassiana at 1×108conidia/ml on newly emerged adults of P. persimilis caused 44% reduction in the oviposition period, 26% in adult longevity, and 63% in fecundity. Due to these negative effects, B. bassiana should be used with careful adjustment of application timing (first spray B. bassiana and then release P. persimilis) to supplement biological mite control systems using P. persimilis.

Reverse allostasis in biological systems: Minimal conditions and implications

Biological control systems regulate the behavior of biological systems in a constantly changing environment. Homeostasis is the most widely studied outcome of biological control systems. Homeostatic systems maintain the system in its desired state despite variations in system parameters or the externally-determined input rates of their constituents, i.e. they have zero or near zero steady state error. On the other hand, allostatic systems are not resistant against environmental changes and the steady state level of their controlled variables responds positively to the changes in their input rates. Little is known, however, on the existence and frequency of reverse allostatic systems, where the steady state value of the controlled variable correlates negatively with the input rate of that variable. In the present study, we derive the minimal conditions for the existence and local stability of reverse allostatic systems, and demonstrate in examples of metabolic, pharmacological, pathophysiological and ecological systems that the reverse allostasis requirements are relatively non-stringent and may be satisfied in biological systems more commonly than usually thought. The possible existence of reverse allostatic systems in nature and their counter-intuitive implications in physiological systems, drug treatment, ecosystem management, and biological control are explored and testable predictions are made.

Effects of Pesticides Used on Table Grapes on the Mealybug Parasitoid Coccidoxenoides peregrinus (Timberlake) (Hymenoptera: Encyrtidae)

The effects of regularly used table grape insecticides and fungicides on 1-day-old adults of the parasitoid Coccidoxenoides peregrinus (Timberlake) of vine mealybug, Planococcus ficus (Signoret), were determined in the laboratory. The insecticides chlorpyrifos, endosulfan and cypermethrin were highly toxic to the parasitoid, while the fungicides penconazole and mancozeb were not. These results suggest that the insecticides may be detrimental to a biological control system using C. peregrinus while the two fungicides tested should be compatible with augmentative releases of C. peregrinus.

Effects of Pesticides and Fungicides Used on Grapevines on the Mealybug Predatory Beetle Nephus 'boschianus' (Coccinellidae, Scymnini)

The effects of frequently used grapevine insecticides and fungicides on adults of the predatory beetle Nephus 'boschianus' of vine mealybug, Planococcus ficus (Signoret), were determined under laboratory conditions. When applied as cover sprays the pesticides chlorpyrifos, endosulfan, cypermethrin, chlorfenapyr and mercaptothion were very toxic to the predator, whilst the fungicides penconazole, fosetyl-Al, mancozeb and an insecticidal soap plus oil mixture were harmless. These results suggest that the insecticides may be harmful to a biological control system where N. 'boschianus' populations were dominant during the season. The three fungicides and the soap plus oil mixture, however, should be compatible with biological control by N. 'boschianus'.

De novo transcriptomic analysis to reveal insecticide action and detoxification-related genes of the predatory bug, Cyrtorhinus lividipennis

The mirid bug, Cyrtorhinus lividipennis Reuter, an important predatory natural enemy of rice planthoppers, is widely distributed in rice fields. However, genetic information on C. lividipennis is lacking. Especially, limited data about mechanisms of insecticide selectivity between this piercing-sucking predator (C. lividipennis) and piercing-sucking preys (rice planthoppers), inhibits development of selective insecticides and the integration of chemical and biological control systems to control insect pests of rice. Hence, we performed de novo assembly of a transcriptome from adult and nymph whole bodies of C. lividipennis. A total of >29 million of reads were generated, and 34,752 transcripts matched known proteins. Then, the genes related to insecticide action and detoxification were manually identified, including 26 carboxylesterases (containing 2 acetylcholinesterases), 57 cytochrome P450s, 19 glutathione S-transferases, 15 nicotinic acetylcholine receptors, 3 GABA-gated ion channels, and 1 glutamate receptor. Comparisons of sequence differences in these genes between C. lividipennis and rice planthoppers, revealed that quite a lot of diversity was found among genes related to insecticide action and detoxification, while a few of these genes share much higher identities between this predator and prey. The present study provides useful information for our understanding of insecticide selectivity between rice planthoppers and the predator mirid bug.

ISOLATION AND IDENTIFICATION OF Pseudomonas spp. TO CONTROL Plasmodiophora brassciae, THE PATHOGEN OF CLUBROOT DISEASE ON CABBAGE

Clubroot is very detrimental disease to cabbage production so as farmers work on various efforts to control it. The use of fungicides not only ineffective but also pollute the environment, therefore biological control system need to be pursued. The use of antagonistic agents such as Pseudomonas has been widely studied and known effective in suppressing various pathogens. Therefore it is worth trying its effectiveness against Plasmodiophora brassicae, a pathogen of cabbage. The purpose of this study was to obtain indigenous Pseudomonas which effectively suppress the pathogens and may also increase plant growth. Microbes were isolated from the cabbage area using the Kings'B medium with multilevel dilution. All isolates were tested for their effectiveness in pots in a Completely Randomized Design with a concentration of 1.5x106 CFU (Colony Forming Unit) per pot. The variables observed were plant growth, number of club roots, and percentage of disease incidence. Fourteen isolates of Pseudomonas were isolated. Three Pseudomonas isolates were found most effective at suppressing clubroot disease and increasing plant growth. The best isolate obtained was Pseudomonas-6, followed Pseudomonas-9, and Pseudomonas-8.

Climate change effects on biological control of invasive plants by insects.

Abstract Because many invasive plants are anticipated to benefit from climate change, the need for effective management strategies will become more pressing in the future. Biological control of invasive plants by insects has been an effective management strategy in many instances, but climate change may substantially alter such systems. Maximizing biological control efficacy with climate change will require predicting responses of the invasive plant in question, its biological control agents, and especially their corresponding interactions. However, because of the wide variety of species-specific plant and insect responses to increased atmospheric CO 2 concentrations, temperatures, extreme weather events, and other climate factors, climate change will likely result in highly variable, system- and geographically-specific effects. Even still, predicted future climates are generally anticipated across systems to alter geographic ranges of invasive plants (and correspondingly their biological agents), reduce host-plant quality, and hasten the phenology of both plants and insects. Some of these anticipated effects on biological control systems can be expected to hamper control efficacy. However, because some of these effects might also increase control efficacy, biological control can still be an effective and important management tool in the face of climate change. Although the variety of insect and plant responses to climate change reported in the literature do not currently allow for strong generalizations to be made as to the best biological control agents or strategies in novel climates, pertinent considerations for selecting effective biological control agents in the future are discussed.

Integrative approach for wastewater treatment facilities with biomass transformation into energy

Current industrial environmental regulations favor processes with Integrative Pollution Prevention and Control (IPPC). While several systems are regarded by different international directives as IPPC Best Available Techniques or Technologies (BAT), none of these systems are capable handling various pollutants of both gaseous and aquatic effluents. Additional hinder to a BAT-IPPC complete procedure are hazardous or uneconomical byproducts of the IPPC processes and significant auxiliary costs for consumables and energy. The current research and subsequent projects are aimed to the development of a Biological Integrative Pollution Prevention and Control (Bio-IPPC) system. Such system can be incorporated in various industrial processes, in a way that the byproduct is without hazardous potential and may be used as an economical raw material. The main initiative and heart of these systems is a micro-algae reactor, which is capable of treating various types of industrial pollutants both in the gaseous and aquatic phases. The algae nutrition is through thin-film circulation of the aquatic effluent and the reactor atmosphere is enriched by flue gases. The excessive algal biomass may be utilized for economic purposes starting with animal feedstock, through organic fertilizer and as industrial raw material for biofuels production or direct energy production. The first industrial project is a wastewater (WW) polishing stage to an industry zone WW treatment facility, which ensures high level effluent purification and assimilation of greenhouse gases, which are released during the WW bioremediation process. The second industrial application aims to treat aquatic and gaseous effluents from coal propelled power plants. The raw algal material from both projects although very different, is used for the development of new efficient scheme for bioethanol production. In summary, the system presented is an actual Bio-IPPC that can interactively treat several industrial effluents, while utilizing the algal biomass as a profitable raw material.

Comparative Studies on in- vitro Phytochemicals Analysis and Larvicidal Efficacy of Medicinal Plant Extracts against Culex quinquefasciatus

Comparative Studies on in- vitro Phytochemicals Analysis and Larvicidal Efficacy of Medicinal Plant Extracts against Culex quinquefasciatus

A systems theoretic approach to analysis and control of mammalian circadian dynamics

The mammalian circadian clock is a complex multi-scale, multivariable biological control system. In the past two decades, methods from systems engineering have led to numerous insights into the architecture and functionality of this system. In this review, we examine the mammalian circadian system through a process systems lens. We present a mathematical framework for examining the cellular circadian oscillator, and show recent extensions for understanding population-scale dynamics. We provide an overview of the routes by which the circadian system can be systemically manipulated, and present in silico proof of concept results for phase resetting of the clock via model predictive control.