scholarly journals Microbial Fuel Cell Based Thermosensor for Robotic Applications

2021 ◽  
Vol 8 ◽  
Author(s):  
John Greenman ◽  
Arjuna Mendis ◽  
Jiseon You ◽  
Iwona Gajda ◽  
Ian Horsfield ◽  
...  
Keyword(s):  
Microbial Fuel Cells ◽  
Load Resistance ◽  
Open Loop ◽  
Time Interval ◽  
Thermal Source ◽  
Thermal Sensing ◽  
Series Of Experiments ◽  
Minimum Interval ◽  
And Function ◽  
Thermal Stimuli

On the roadmap to building completely autonomous artificial bio-robots, all major aspects of robotic functions, namely, energy generation, processing, sensing, and actuation, need to be self-sustainable and function in the biological realm. Microbial Fuel Cells (MFCs) provide a platform technology for achieving this goal. In a series of experiments, we demonstrate that MFCs can be used as living, autonomous sensors in robotics. In this work, we focus on thermal sensing that is akin to thermoreceptors in mammalian entities. We therefore designed and tested an MFC-based thermosensor system for utilization within artificial bio-robots such as EcoBots. In open-loop sensor characterization, with a controlled load resistance and feed rate, the MFC thermoreceptor was able to detect stimuli of 1 min directed from a distance of 10 cm causing a temperature rise of ∼1°C at the thermoreceptor. The thermoreceptor responded to continuous stimuli with a minimum interval of 384 s. In a practical demonstration, a mobile robot was fitted with two artificial thermosensors, as environmental thermal detectors for thermotactic application, mimicking thermotaxis in biology. In closed-loop applications, continuous thermal stimuli were detected at a minimum time interval of 160 s, without the need for complete thermoreceptor recovery. This enabled the robot to detect thermal stimuli and steer away from a warmer thermal source within the rise of 1°C. We envision that the thermosensor can be used for future applications in robotics, including as a potential sensor mechanism for maintaining thermal homeostasis.

scholarly journals Recovery of dynamics and function in spiking neural networks by closed-loop control

2015 ◽  
Author(s):  
Ioannis Vlachos ◽  
Taskin Deniz ◽  
Ad Aertsen ◽  
Arvind Kumar
Keyword(s):  
Neural Networks ◽  
Closed Loop ◽  
Brain Activity ◽  
Open Loop ◽  
Spiking Neural Networks ◽  
Delayed Feedback Control ◽  
Loop Control ◽  
Wide Range ◽  
Underlying Network ◽  
And Function

There is a growing interest in developing novel brain stimulation methods to control disease-related aberrant neural activity and to address basic neuroscience questions. Conventional methods for manipulating brain activity rely on open-loop approaches that usually lead to excessive stimulation and, crucially, do not restore the original computations performed by the network. Thus, they are often accompanied by undesired side-effects. Here, we introduce delayed feedback control (DFC), a conceptually simple but effective method, to control pathological oscillations in spiking neural networks. Using mathematical analysis and numerical simulations we show that DFC can restore a wide range of aberrant network dynamics either by suppressing or enhancing synchronous irregular activity. Importantly, DFC besides steering the system back to a healthy state, it also recovers the computations performed by the underlying network. Finally, using our theory we isolate the role of single neuron and synapse properties in determining the stability of the closed-loop system.

Active harvesting enhances energy recovery and function of electroactive microbiomes in microbial fuel cells

2019 ◽  
Vol 247 ◽  
pp. 492-502 ◽  
Author(s):  
Lu Lu ◽  
Fernanda Leite Lobo ◽  
Defeng Xing ◽  
Zhiyong Jason Ren
Keyword(s):  
Fuel Cells ◽  
Microbial Fuel Cells ◽  
Energy Recovery ◽  
And Function

Modeling Uncertainty for Planar Meso-Scale Manipulation and Assembly

2006 ◽  
Author(s):  
David J. Cappelleri ◽  
Jonathan Fink ◽  
Vijay Kumar
Keyword(s):  
Manufacturing Industry ◽  
Surface Friction ◽  
Open Loop ◽  
Robotic Assembly ◽  
Planar Surface ◽  
Single Probe ◽  
Grasping And Manipulation ◽  
Static Operation ◽  
Series Of Experiments ◽  
Meso Scale

While robotic assembly at the centimeter and meter length scale is well understood and is routine in the manufacturing industry, robotic grasping and manipulation for meso-scale assembly at the millimeter and sub-millimeter length scales are much more difficult. This paper explores an possible way to manipulate and assemble planar parts using a micro-manipulator with a single probe capable of pushing parts on a planar surface with visual feedback. Specifically, we describe a study of the uncertainty associated with planar surface friction with a goal of developing a model of manipulation primitives that can be used for assembly. We describe a series of experiments and data analysis algorithms that allow us to identify the main system parameters for quasi-static operation, including the friction coefficient and the force distribution, while characterizing the uncertainty associated with these parameters. This allows us to bound the range of motions resulting from the uncertainty, which is necessary to design robust open-loop meso-scale manipulation and assembly motion plans.

Packing Characteristics and Its Effect on Heat Transfer Characteristics in Melting of Granular Packed Bed Subject to Horizonal Forced Convection

2002 ◽  
Author(s):  
Y. L. Hao ◽  
Y.-X. Tao
Keyword(s):  
Heat Transfer ◽  
Forced Convection ◽  
Melting Process ◽  
Packed Bed ◽  
Time Interval ◽  
Heat Transfer Characteristics ◽  
Transfer Characteristics ◽  
Ice Particles ◽  
Different Types ◽  
Series Of Experiments

A series of experiments are conducted to investigate the characteristics and its effect on the melting and heat of a packed bed consisting of melting ice particles to horizontal forced convection. The volumes and situations of the melting ganular packed beds are by the visualization observations and measurements digital camcorders within the range of Re = 71 ~ 2291, Gr/Re2 = 1.48×10−5 ~ 17.32, and Ste = 0.0444 ~ 0.385, respectively. The mass of ice particles is measured at the time interval during the melting process. Two types of pattern can be found under the different conditions. The different types of heat transfer characteristics emerge in type of packing pattern. The correlations for each type of pattern are obtained based on the experimental results.

scholarly journals When COVID-19 affects muscle: effects of quarantine in older adults

2020 ◽  
Author(s):  
Tatiana Moro ◽  
Antonio Paoli
Keyword(s):  
Older Adults ◽  
Physical Inactivity ◽  
Load Resistance ◽  
Preventive Action ◽  
The Past ◽  
Low Load ◽  
Increase Risk ◽  
Risk Of Fall ◽  
And Function ◽  
Negative Health Outcomes

At the beginning of 2020 a respiratory diseased named COVID-19 rapidly spread worldwide. Due to the presence of comorbidities and a greater susceptibility to infections, older adults are the population most affected by this pandemic. An efficient pharmacological treatment for COVID-19 is not ready yet; in the meanwhile, a general quarantine has been initiated as a preventive action against the spread of the disease.  If on one side this countermeasure is slowing the spread of the virus, on the other side is also reducing the amount of physical activity. Sedentariness is associated with numerous negative health outcomes and increase risk of fall, fractures and disabilities in older adults. Models of physical inactivity have been widely studied in the past decades, and most studies agreed that is necessary to implement physical exercise (such as walking, low load resistance or in bed exercise) during periods of disuse to protect muscle mass and function from catabolic crisis. Moreover, older adults have a blunted response to physical rehabilitation, and a combination of intense resistance training and nutrition are necessary to overcome the loss of in skeletal muscle due to disuse.

scholarly journals CELLULAR DIFFERENTIATION OF THE IMMUNE SYSTEM OF MICE

1969 ◽  
Vol 129 (5) ◽  
pp. 935-951 ◽  
Author(s):  
G. M. Shearer ◽  
G. Cudkowicz
Keyword(s):  
Immune Response ◽  
Immune System ◽  
Cellular Differentiation ◽  
Marrow Cell ◽  
The Other ◽  
Cell Type ◽  
Series Of Experiments ◽  
And Function ◽  
Thymus Cells ◽  
Marrow Cells

Marrow cell suspensions of unprimed donor mice have been transplanted into X-irradiated syngeneic hosts. 5–46 days later, bone cavities and spleens contained regenerated cells of the immune system which required interaction with thymocytes (from intact donors) and antigen (SRBC) to form antigen-sensitive units (ASU) and to generate mature immunocytes. These cells were capable of differentiating either into direct or indirect hemolytic plaque-forming cells (PFC). The precursors of PFC regenerated earlier than the other cell type necessary for immunocompetence, the antigen-reactive cell (ARC). The latter was not found until 10 or more days after transplantation. Availability of ARC was inferred from PFC responses elicited by grafted mice challenged with SRBC at varying intervals. In a second series of experiments, graded numbers of marrow cells (ranging from 107 to 5 x 107) were transplanted with 5 x 107 or 108 thymocytes into irradiated mice, and SRBC were given 18 hr later. After 9–12 days the recipient spleens contained all or some of the following immunocytes: direct and indirect PFC, and hemagglutinating cluster-forming cells. The frequency of each immune response varied independently of the others, but in relation to the number of marrow cells grafted. This was interpreted to indicate that ASU formed in irradiated mice by interaction of marrow and thymus cells were similar to those of intact mice. In particular, they were specialized for the molecular class (IgM or IgG) and function (lysis or agglutination) of the antibody to be secreted by their descendent immunocytes. Hence, class-differentiation appeared to be conferred upon ASU by their marrow-derived components.

The detection and perceived intensity of noxious thermal stimuli in monkey and in human

1989 ◽  
Vol 62 (2) ◽  
pp. 429-436 ◽  
Author(s):  
D. R. Kenshalo ◽  
F. Anton ◽  
R. Dubner
Keyword(s):  
Human Subjects ◽  
Time Interval ◽  
Perceived Intensity ◽  
The Face ◽  
The Subject ◽  
T1 And T2 ◽  
Thermal Stimuli ◽  
Detection Speed ◽  
Stimulation Of ◽  
Volar Surface

1. The magnitude of the sensations produced by small increases in thermal stimuli superimposed on noxious levels of heat stimulation was studied by the use of a simple reaction-time task. Noxious thermal stimuli were presented on the face of three monkeys, the forearm volar surface of three monkeys, and the face of four human subjects. The subject, either monkey or human, initiated a trial by pressing an illuminated button. Subsequently, a contact thermode increased in temperature from a base line of 38 degree C to temperatures of 44, 45, 46, or 47 degrees C (T1). After a variable time period lasting between 4 and 10 s, the thermode temperature increased an additional 0.1, 0.2, 0.4, 0.6, or 0.8 degrees C (T2). The subject was required to release the button as soon as the T2 stimulus was detected. Detection latency, expressed as its reciprocal, detection speed, was defined as the time interval between the onset of T2 and the release of the button. 2. The monkeys' detection speed to stimuli presented on the upper lip was dependent on the intensity of both T1 and T2. Increases in the intensity of T2 between 0.1 and 0.8 degrees C produced faster detection speeds. In general, as the intensity of T1 increased, the detection speed increased to identical T2 stimuli. The monkeys' T2-detection threshold was also dependent on the intensity of T1. 3. The psychophysical functions obtained from stimulation of the monkey's face were compared with those obtained from the volar surface of the monkey's forearm. Whereas the T2 thresholds obtained from stimulation of the monkey's forearm and face were similar, the psychophysical functions obtained from stimulation of the face were significantly steeper than those obtained from stimulation of the forearm. 4. The humans' detection speed of T2 stimuli presented on the face was monotonically related to the intensity of T2 and was dependent on the level of T1. The psychophysical functions obtained from the human's face were equivalent to those obtained from the monkey's faces. 5. A cross-modality matching procedure was used to examine the perceived intensity of pain sensation produced by T2 stimuli in human subjects. The magnitude estimates of these stimuli were dependent on the level of T1, as well as the intensity of T2. Detection speed, plotted as a function of the estimated magnitude of pain, independent of T1 and T2 temperature, was best fit by a logarithmic function.(ABSTRACT TRUNCATED AT 400 WORDS)

The quest to achieve the detailed structural and functional characterization of CymA

2012 ◽  
Vol 40 (6) ◽  
pp. 1291-1294 ◽  
Author(s):  
Ricardo O. Louro ◽  
Catarina M. Paquete
Keyword(s):  
Microbial Fuel Cells ◽  
Critical Role ◽  
Functional Characterization ◽  
Shewanella Oneidensis ◽  
Model Organism ◽  
Structural Behaviour ◽  
Metal Compounds ◽  
Potential Applications ◽  
And Function

Shewanella oneidensis MR-1 is a sediment organism capable of dissimilatory reduction of insoluble metal compounds such as those of Fe(II) and Mn(IV). This bacterium has been used as a model organism for potential applications in bioremediation of contaminated environments and in the production of energy in microbial fuel cells. The capacity of Shewanella to perform extracellular reduction of metals is linked to the action of several multihaem cytochromes that may be periplasmic or can be associated with the inner or outer membrane. One of these cytochromes is CymA, a membrane-bound tetrahaem cytochrome localized in the periplasm that mediates the electron transfer between the quinone pool in the cytoplasmic membrane and several periplasmic proteins. Although CymA has the capacity to regulate multiple anaerobic respiratory pathways, little is known about the structure and functional mechanisms of this focal protein. Understanding the structure and function of membrane proteins is hampered by inherent difficulties associated with their purification since the choice of the detergents play a critical role in the protein structure and stability. In the present mini-review, we detail the current state of the art in the characterization of CymA, and add recent information on haem structural behaviour for CymA solubilized in different detergents. These structural differences are deduced from NMR spectroscopy data that provide information on the geometry of the haem axial ligands. At least two different conformational forms of CymA are observed for different detergents, which seem to be related to the micelle size. These results provide guidance for the discovery of the most promising detergent that mimics the native lipid bilayer and is compatible with biochemical and structural studies.

A Wireless Microbial Fuel Cell Voltage Data Acquisition System Based on MSP430F149

2011 ◽  
Vol 105-107 ◽  
pp. 1961-1965 ◽  
Author(s):  
Kai Liu ◽  
Zhi Wei Zhao ◽  
He Long Jiang
Keyword(s):  
Fuel Cell ◽  
Data Acquisition ◽  
Microbial Fuel Cell ◽  
Microbial Fuel Cells ◽  
Data Acquisition System ◽  
Acquisition System ◽  
Time Interval ◽  
Main Function ◽  
Usb Interface ◽  
Gsm Network

A wireless data acquisition system based on MSP430F149 is developed for the measurement of microbial fuel cells’ voltage. The main function of this system is to convert the analog input voltage into digital output code, process the digital code, and transfer the data through the GSM network or the USB interface. The core of the data acquisition device is a 16-bit general purpose Texas Instruments ultralow-power microcontroller MSP430F149. As the voltage of a microbial fuel cell is very low, the A/D converter circuit is specifically designed for high precision and high accuracy. A real-time clock is used to achieve timing measurement and the time interval can be set to meet demands. The data collected is transferred through the GSM network. Besides, a Windows environment application developed with Visual C++ can be used to access the data stored in the flash memory through USB interface.

scholarly journals A Methodology for Multihazards Load Combinations of Earthquake and Heavy Trucks for Bridges

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Dezhang Sun ◽  
Xu Wang ◽  
Baitao Sun
Keyword(s):  
Random Process ◽  
Random Variables ◽  
Load Resistance ◽  
Time Interval ◽  
Modified Model ◽  
Heavy Trucks ◽  
Extreme Load ◽  
Earthquake Load ◽  
Heavy Truck ◽  
Truck Load

Issues of load combinations of earthquakes and heavy trucks are important contents in multihazards bridge design. Currentload resistance factor design(LRFD)specificationsusually treat extreme hazards alone and have no probabilistic basis in extreme load combinations. Earthquake load and heavy truck load are considered as random processes with respective characteristics, and the maximum combined load is not the simple superimposition of their maximum loads. Traditional Ferry Borges-Castaneda model that considers load lasting duration and occurrence probability well describes random process converting to random variables and load combinations, but this model has strict constraint in time interval selection to obtain precise results. Turkstra’s rule considers one load reaching its maximum value in bridge’s service life combined with another load with its instantaneous value (or mean value), which looks more rational, but the results are generally unconservative. Therefore, a modified model is presented here considering both advantages of Ferry Borges-Castaneda's model and Turkstra’s rule. The modified model is based on conditional probability, which can convert random process to random variables relatively easily and consider the nonmaximum factor in load combinations. Earthquake load and heavy truck load combinations are employed to illustrate the model. Finally, the results of a numerical simulation are used to verify the feasibility and rationality of the model.

Sign in / Sign up

Export Citation Format

Share Document