Performance Characteristics of Bio-Inspired Metal Nanostructures as Surface-Enhanced Raman Scattered (SERS) Substrates.

PubMed

Areizaga-Martinez, Hector I; Kravchenko, Ivan; Lavrik, Nickolay V; Sepaniak, Michael J; Hernández-Rivera, Samuel P; De Jesús, Marco A

2016-09-01

The fabrication of high-performance plasmonic nanomaterials for bio-sensing and trace chemical detection is a field of intense theoretical and experimental research. The use of metal-silicon nanopillar arrays as analytical sensors has been reported with reasonable results in recent years. The use of bio-inspired nanocomposite structures that follow the Fibonacci numerical architecture offers the opportunity to develop nanostructures with theoretically higher and more reproducible plasmonic fields over extended areas. The work presented here describes the nanofabrication process for a series of 40 µm × 40 µm bio-inspired arrays classified as asymmetric fractals (sunflower seeds and romanesco broccoli), bilaterally symmetric (acacia leaves and honeycombs), and radially symmetric (such as orchids and lily flowers) using electron beam lithography. In addition, analytical capabilities were evaluated using surface-enhanced Raman scattering (SERS). The substrate characterization and SERS performance of the developed substrates as the strategies to assess the design performance are presented and discussed. © The Author(s) 2016.

A bio-inspired electrocommunication system for small underwater robots.

PubMed

Wang, Wei; Liu, Jindong; Xie, Guangming; Wen, Li; Zhang, Jianwei

2017-03-29

Weakly electric fishes (Gymnotid and Mormyrid) use an electric field to communicate efficiently (termed electrocommunication) in the turbid waters of confined spaces where other communication modalities fail. Inspired by this biological phenomenon, we design an artificial electrocommunication system for small underwater robots and explore the capabilities of such an underwater robotic communication system. An analytical model for electrocommunication is derived to predict the effect of the key parameters such as electrode distance and emitter current of the system on the communication performance. According to this model, a low-dissipation, and small-sized electrocommunication system is proposed and integrated into a small robotic fish. We characterize the communication performance of the robot in still water, flowing water, water with obstacles and natural water conditions. The results show that underwater robots are able to communicate electrically at a speed of around 1 k baud within about 3 m with a low power consumption (less than 1 W). In addition, we demonstrate that two leader-follower robots successfully achieve motion synchronization through electrocommunication in the three-dimensional underwater space, indicating that this bio-inspired electrocommunication system is a promising setup for the interaction of small underwater robots.

SABRE: a bio-inspired fault-tolerant electronic architecture.

PubMed

Bremner, P; Liu, Y; Samie, M; Dragffy, G; Pipe, A G; Tempesti, G; Timmis, J; Tyrrell, A M

2013-03-01

As electronic devices become increasingly complex, ensuring their reliable, fault-free operation is becoming correspondingly more challenging. It can be observed that, in spite of their complexity, biological systems are highly reliable and fault tolerant. Hence, we are motivated to take inspiration for biological systems in the design of electronic ones. In SABRE (self-healing cellular architectures for biologically inspired highly reliable electronic systems), we have designed a bio-inspired fault-tolerant hierarchical architecture for this purpose. As in biology, the foundation for the whole system is cellular in nature, with each cell able to detect faults in its operation and trigger intra-cellular or extra-cellular repair as required. At the next level in the hierarchy, arrays of cells are configured and controlled as function units in a transport triggered architecture (TTA), which is able to perform partial-dynamic reconfiguration to rectify problems that cannot be solved at the cellular level. Each TTA is, in turn, part of a larger multi-processor system which employs coarser grain reconfiguration to tolerate faults that cause a processor to fail. In this paper, we describe the details of operation of each layer of the SABRE hierarchy, and how these layers interact to provide a high systemic level of fault tolerance.

Bio-Inspired Human-Level Machine Learning

DTIC Science & Technology

2015-10-25

extensions to high-level cognitive functions such as anagram solving problem. 15. SUBJECT TERMS 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF...extensions to high-level cognitive functions such as anagram solving problem. We expect that the bio-inspired human-level machine learning combined with...numbers of 1011 neurons and 1014 synaptic connections in the human brain. In previous work, we experimentally demonstrated the feasibility of cognitive

How flexibility and dynamic ground effect could improve bio-inspired propulsion

NASA Astrophysics Data System (ADS)

Quinn, Daniel

2016-11-01

Swimming animals use complex fin motions to reach remarkable levels of efficiency, maneuverability, and stealth. Propulsion systems inspired by these motions could usher in a new generation of advanced underwater vehicles. Two aspects of bio-inspired propulsion are discussed here: flexibility and near-boundary swimming. Experimental work on flexible propulsors shows that swimming efficiency depends on wake vortex timing and boundary layer attachment, but also on fluid-structure resonance. As a result, flexible vehicles or animals could potentially improve their performance by tracking their resonance properties. Bio-inspired propulsors were also found to produce more thrust with no loss in efficiency when swimming near a solid boundary. Higher lift-to-drag ratios for near-ground fixed-wing gliders is commonly known as ground effect. This newly observed "dynamic ground effect" suggests that bio-inspired vehicles and animals could save energy by harnessing the performance gains associated with near-boundary swimming. This work was supported by the Office of Naval Research (MURI N00014-08-1-0642, Program Director Dr. Bob Brizzolara) and the National Science Foundation (DBI-1062052, PI Lisa Fauci; EFRI-0938043, PI George Lauder).

Eigen values in epidemic and other bio-inspired models

NASA Astrophysics Data System (ADS)

Supriatna, A. K.; Anggriani, N.; Carnia, E.; Raihan, A.

2017-08-01

Eigen values and the largest eigen value have special roles in many applications. In this paper we will discuss its role in determining the epidemic threshold in which we can determine if an epidemic will decease or blow out eventually. Some examples and their consequences to controling the epidemic are also discusses. Beside the application in epidemic model, the paper also discusses other example of appication in bio-inspired model, such as the backcross breeding for two age classes of local and exotic goats. Here we give some elaborative examples on the use of previous backcross breeding model. Some future direction on the exploration of the relationship between these eigenvalues to different epidemic models and other bio-inspired models are also presented.

High-performance flexible strain sensor with bio-inspired crack arrays.

PubMed

Han, Zhiwu; Liu, Linpeng; Zhang, Junqiu; Han, Qigang; Wang, Kejun; Song, Honglie; Wang, Ze; Jiao, Zhibin; Niu, Shichao; Ren, Luquan

2018-06-12

Biomimetic sensor technology is always superior to existing human technologies. The scorpion, especially the forest scorpion, has a unique ability to detect subtle vibrations, which is attributed to the microcrack-shaped slit sensillum on its legs. Here, the biological sensing mechanism of the typical scorpion (Heterometrus petersii) was intensively studied in order to newly design and significantly improve the flexible strain sensors. Benefiting from the easy-crack property of polystyrene (PS) and using the solvent-induced swelling as well as double template transferring method, regular and controllable microcrack arrays were successfully fabricated on top of polydimethylsiloxane (PDMS). Using this method, any physical damage to PDMS could be effectively avoided. More fortunately, this bio-inspired crack arrays fabricated in this work also had a radial-like pattern similar to the slit sensillum of the scorpion, which was another unexpected imitation. The gauge factor (GF) of the sensor was conservatively evaluated at 5888.89 upon 2% strain and the response time was 297 ms. Afterward, it was demonstrated that the bio-inspired regular microcrack arrays could also significantly enhance the performance of traditional strain sensors, especially in terms of the sensitivity and response time. The practical applications, such as the detection of human motions and surface folding, were also tested in this work, with the results showing significant potential applications in numerous fields. This work changes the traditional waste cracks on some damaged products into valuable things for ultrasensitive mechanical sensors. Moreover, with this manufacturing technique, we could easily realize the simple, low cost and large-scale fabrication of advanced bioinpired sensors.

Bio-Inspired Navigation of Chemical Plumes

DTIC Science & Technology

2006-07-01

Bio-Inspired Navigation of Chemical Plumes Maynard J. Porter III, Captain, USAF Department of Electrical and Computer Engineering Air Force Institute...Li. " Chemical plume tracing via an autonomous underwater vehicle". IEEE Journal of Ocean Engineering , 30(2):428— 442, 2005. [6] G. A. Nevitt...Electrical and Computer Engineering Air Force Institute of Technology Dayton, OH 45433-7765, U.S.A. juan.vasquez@afit.edu May 31, 2006 Abstract - The

Novel Bio-inspired Aquatic Flow Sensors

DTIC Science & Technology

2012-06-18

Novel Bio-inspired Aquatic Flow Sensors Preston Albert Pinto Thesis submitted to the Faculty of the Virginia Polytechnic Institute and...Leo, Chair Stephen A. Sarles Michael K. Philen Pavlos Vlachos June 18th, 2012 Blacksburg, Virginia Keywords: artificial hair cell, flow ...Aquatic Flow Sensors 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT

Switchable bio-inspired adhesives

NASA Astrophysics Data System (ADS)

Kroner, Elmar

2015-03-01

Geckos have astonishing climbing abilities. They can adhere to almost any surface and can run on walls and even stick to ceilings. The extraordinary adhesion performance is caused by a combination of a complex surface pattern on their toes and the biomechanics of its movement. These biological dry adhesives have been intensely investigated during recent years because of the unique combination of adhesive properties. They provide high adhesion, allow for easy detachment, can be removed residue-free, and have self-cleaning properties. Many aspects have been successfully mimicked, leading to artificial, bio-inspired, patterned dry adhesives, and were addressed and in some aspects they even outperform the adhesion capabilities of geckos. However, designing artificial patterned adhesion systems with switchable adhesion remains a big challenge; the gecko's adhesion system is based on a complex hierarchical surface structure and on advanced biomechanics, which are both difficult to mimic. In this paper, two approaches are presented to achieve switchable adhesion. The first approach is based on a patterned polydimethylsiloxane (PDMS) polymer, where adhesion can be switched on and off by applying a low and a high compressive preload. The switch in adhesion is caused by a reversible mechanical instability of the adhesive silicone structures. The second approach is based on a composite material consisting of a Nickel- Titanium (NiTi) shape memory alloy and a patterned adhesive PDMS layer. The NiTi alloy is trained to change its surface topography as a function of temperature, which results in a change of the contact area and of alignment of the adhesive pattern towards a substrate, leading to switchable adhesion. These examples show that the unique properties of bio-inspired adhesives can be greatly improved by new concepts such as mechanical instability or by the use of active materials which react to external stimuli.

Bio-Inspired Controller on an FPGA Applied to Closed-Loop Diaphragmatic Stimulation

PubMed Central

Zbrzeski, Adeline; Bornat, Yannick; Hillen, Brian; Siu, Ricardo; Abbas, James; Jung, Ranu; Renaud, Sylvie

2016-01-01

Cervical spinal cord injury can disrupt connections between the brain respiratory network and the respiratory muscles which can lead to partial or complete loss of ventilatory control and require ventilatory assistance. Unlike current open-loop technology, a closed-loop diaphragmatic pacing system could overcome the drawbacks of manual titration as well as respond to changing ventilation requirements. We present an original bio-inspired assistive technology for real-time ventilation assistance, implemented in a digital configurable Field Programmable Gate Array (FPGA). The bio-inspired controller, which is a spiking neural network (SNN) inspired by the medullary respiratory network, is as robust as a classic controller while having a flexible, low-power and low-cost hardware design. The system was simulated in MATLAB with FPGA-specific constraints and tested with a computational model of rat breathing; the model reproduced experimentally collected respiratory data in eupneic animals. The open-loop version of the bio-inspired controller was implemented on the FPGA. Electrical test bench characterizations confirmed the system functionality. Open and closed-loop paradigm simulations were simulated to test the FPGA system real-time behavior using the rat computational model. The closed-loop system monitors breathing and changes in respiratory demands to drive diaphragmatic stimulation. The simulated results inform future acute animal experiments and constitute the first step toward the development of a neuromorphic, adaptive, compact, low-power, implantable device. The bio-inspired hardware design optimizes the FPGA resource and time costs while harnessing the computational power of spike-based neuromorphic hardware. Its real-time feature makes it suitable for in vivo applications. PMID:27378844

Bio-inspired self-shaping ceramics

PubMed Central

Bargardi, Fabio L.; Le Ferrand, Hortense; Libanori, Rafael; Studart, André R.

2016-01-01

Shaping ceramics into complex and intricate geometries using cost-effective processes is desirable in many applications but still remains an open challenge. Inspired by plant seed dispersal units that self-fold on differential swelling, we demonstrate that self-shaping can be implemented in ceramics by programming the material's microstructure to undergo local anisotropic shrinkage during heat treatment. Such microstructural design is achieved by magnetically aligning functionalized ceramic platelets in a liquid ceramic suspension, subsequently consolidated through an established enzyme-catalysed reaction. By fabricating alumina compacts exhibiting bio-inspired bilayer architectures, we achieve deliberate control over shape change during the sintering step. Bending, twisting or combinations of these two basic movements can be successfully programmed to obtain a myriad of complex shapes. The simplicity and the universality of such a bottom-up shaping method makes it attractive for applications that would benefit from low-waste ceramic fabrication, temperature-resistant interlocking structures or unusual geometries not accessible using conventional top–down manufacturing. PMID:28008930

Bio-inspired self-shaping ceramics

NASA Astrophysics Data System (ADS)

Bargardi, Fabio L.; Le Ferrand, Hortense; Libanori, Rafael; Studart, André R.

2016-12-01

Shaping ceramics into complex and intricate geometries using cost-effective processes is desirable in many applications but still remains an open challenge. Inspired by plant seed dispersal units that self-fold on differential swelling, we demonstrate that self-shaping can be implemented in ceramics by programming the material's microstructure to undergo local anisotropic shrinkage during heat treatment. Such microstructural design is achieved by magnetically aligning functionalized ceramic platelets in a liquid ceramic suspension, subsequently consolidated through an established enzyme-catalysed reaction. By fabricating alumina compacts exhibiting bio-inspired bilayer architectures, we achieve deliberate control over shape change during the sintering step. Bending, twisting or combinations of these two basic movements can be successfully programmed to obtain a myriad of complex shapes. The simplicity and the universality of such a bottom-up shaping method makes it attractive for applications that would benefit from low-waste ceramic fabrication, temperature-resistant interlocking structures or unusual geometries not accessible using conventional top-down manufacturing.

Spontaneous water filtration of bio-inspired membrane

NASA Astrophysics Data System (ADS)

Kim, Kiwoong; Kim, Hyejeong; Lee, Sang Joon

2016-11-01

Water is one of the most important elements for plants, because it is essential for various metabolic activities. Thus, water management systems of vascular plants, such as water collection and water filtration have been optimized through a long history. In this view point, bio-inspired technologies can be developed by mimicking the nature's strategies for the survival of the fittest. However, most of the underlying biophysical features of the optimized water management systems remain unsolved In this study, the biophysical characteristics of water filtration phenomena in the roots of mangrove are experimentally investigated. To understand water-filtration features of the mangrove, the morphological structures of its roots are analyzed. The electrokinetic properties of the root surface are also examined. Based on the quantitatively analyzed information, filtration of sodium ions in the roots are visualized. Motivated by this mechanism, spontaneous desalination mechanism in the root of mangrove is proposed by combining the electrokinetics and hydrodynamic transportation of ions. This study would be helpful for understanding the water-filtration mechanism of the roots of mangrove and developing a new bio-inspired desalination technology. This research was financially supported by the National Research Foundation (NRF) of Korea (Contract Grant Number: 2008-0061991).

Aerodynamics of a bio-inspired flexible flapping-wing micro air vehicle.

PubMed

Nakata, T; Liu, H; Tanaka, Y; Nishihashi, N; Wang, X; Sato, A

2011-12-01

MAVs (micro air vehicles) with a maximal dimension of 15 cm and nominal flight speeds of around 10 m s⁻¹, operate in a Reynolds number regime of 10⁵ or lower, in which most natural flyers including insects, bats and birds fly. Furthermore, due to their light weight and low flight speed, the MAVs' flight characteristics are substantially affected by environmental factors such as wind gust. Like natural flyers, the wing structures of MAVs are often flexible and tend to deform during flight. Consequently, the aero/fluid and structural dynamics of these flyers are closely linked to each other, making the entire flight vehicle difficult to analyze. We have recently developed a hummingbird-inspired, flapping flexible wing MAV with a weight of 2.4-3.0 g and a wingspan of 10-12 cm. In this study, we carry out an integrated study of the flexible wing aerodynamics of this flapping MAV by combining an in-house computational fluid dynamic (CFD) method and wind tunnel experiments. A CFD model that has a realistic wing planform and can mimic realistic flexible wing kinematics is established, which provides a quantitative prediction of unsteady aerodynamics of the four-winged MAV in terms of vortex and wake structures and their relationship with aerodynamic force generation. Wind tunnel experiments further confirm the effectiveness of the clap and fling mechanism employed in this bio-inspired MAV as well as the importance of the wing flexibility in designing small flapping-wing MAVs.

Bio-inspired UAV routing, source localization, and acoustic signature classification for persistent surveillance

NASA Astrophysics Data System (ADS)

Burman, Jerry; Hespanha, Joao; Madhow, Upamanyu; Pham, Tien

2011-06-01

A team consisting of Teledyne Scientific Company, the University of California at Santa Barbara and the Army Research Laboratory* is developing technologies in support of automated data exfiltration from heterogeneous battlefield sensor networks to enhance situational awareness for dismounts and command echelons. Unmanned aerial vehicles (UAV) provide an effective means to autonomously collect data from a sparse network of unattended ground sensors (UGSs) that cannot communicate with each other. UAVs are used to reduce the system reaction time by generating autonomous collection routes that are data-driven. Bio-inspired techniques for search provide a novel strategy to detect, capture and fuse data. A fast and accurate method has been developed to localize an event by fusing data from a sparse number of UGSs. This technique uses a bio-inspired algorithm based on chemotaxis or the motion of bacteria seeking nutrients in their environment. A unique acoustic event classification algorithm was also developed based on using swarm optimization. Additional studies addressed the problem of routing multiple UAVs, optimally placing sensors in the field and locating the source of gunfire at helicopters. A field test was conducted in November of 2009 at Camp Roberts, CA. The field test results showed that a system controlled by bio-inspired software algorithms can autonomously detect and locate the source of an acoustic event with very high accuracy and visually verify the event. In nine independent test runs of a UAV, the system autonomously located the position of an explosion nine times with an average accuracy of 3 meters. The time required to perform source localization using the UAV was on the order of a few minutes based on UAV flight times. In June 2011, additional field tests of the system will be performed and will include multiple acoustic events, optimal sensor placement based on acoustic phenomenology and the use of the International Technology Alliance (ITA

Bio-inspired polarized skylight navigation: a review

NASA Astrophysics Data System (ADS)

Zhang, Xi; Wan, Yongqin; Li, Lijing

2015-12-01

The idea of using skylight polarization in navigation is learned from animals such as desert ants and honeybees. Various research groups have been working on the development of novel navigation systems inspired by polarized skylight. The research of background in polarized skylight navigation is introduced, and basic principle of the insects navigation is expatiated. Then, the research progress status at home and abroad in skylight polarization pattern, three bio-inspired polarized skylight navigation sensors and polarized skylight navigation are reviewed. Finally, the research focuses in the field of polarized skylight navigation are analyzed. At the same time, the trend of development and prospect in the future are predicted. It is believed that the review is helpful to people understand polarized skylight navigation and polarized skylight navigation sensors.

Bio-Inspired Networking — Self-Organizing Networked Embedded Systems

NASA Astrophysics Data System (ADS)

Dressler, Falko

The turn to nature has brought us many unforeseen great concepts and solutions. This course seems to hold on for many research domains. In this article, we study the applicability of biological mechanisms and techniques in the domain of communications. In particular, we study the behavior and the challenges in networked embedded systems that are meant to self-organize in large groups of nodes. Application examples include wireless sensor networks and sensor/actuator networks. Based on a review of the needs and requirements in such networks, we study selected bio-inspired networking approaches that claim to outperform other methods in specific domains. We study mechanisms in swarm intelligence, the artificial immune system, and approaches based on investigations on the cellular signaling pathways. As a major conclusion, we derive that bio-inspired networking techniques do have advantages compared to engineering methods. Nevertheless, selection and employment must be done carefully to achieve the desired performance gains.

Case study: Optimizing fault model input parameters using bio-inspired algorithms

NASA Astrophysics Data System (ADS)

Plucar, Jan; Grunt, Onřej; Zelinka, Ivan

2017-07-01

We present a case study that demonstrates a bio-inspired approach in the process of finding optimal parameters for GSM fault model. This model is constructed using Petri Nets approach it represents dynamic model of GSM network environment in the suburban areas of Ostrava city (Czech Republic). We have been faced with a task of finding optimal parameters for an application that requires high amount of data transfers between the application itself and secure servers located in datacenter. In order to find the optimal set of parameters we employ bio-inspired algorithms such as Differential Evolution (DE) or Self Organizing Migrating Algorithm (SOMA). In this paper we present use of these algorithms, compare results and judge their performance in fault probability mitigation.

Bio-inspired scale-like surface textures and their tribological properties.

PubMed

Greiner, Christian; Schäfer, Michael

2015-06-30

Friction, wear and the associated energy dissipation are major challenges in all systems containing moving parts. Examples range from nanoelectromechanical systems over hip prosthesis to off-shore wind turbines. Bionic approaches have proven to be very successful in many engineering problems, while investigating the potential of a bio-inspired approach in creating morphological surface textures is a relatively new field of research. Here, we developed laser-created textures inspired by the scales found on the skin of snakes and certain lizards. We show that this bio-inspired surface morphology reduced dry sliding friction forces by more than 40%. In lubricated contacts the same morphology increased friction by a factor of three. Two different kinds of morphologies, one with completely overlapping scales and one with the scales arranged in individual rows, were chosen. In lubricated as well as unlubricated contacts, the surface texture with the scales in rows showed lower friction forces than the completely overlapping ones. We anticipate that these results could have significant impact in all dry sliding contacts, ranging from nanoelectromechanical and micro-positioning systems up to large-scale tribological contacts which cannot be lubricated, e.g. because they are employed in a vacuum environment.

Methodology for Designing and Developing a New Ultra-Wideband Antenna Based on Bio-Inspired Optimization Techniques

DTIC Science & Technology

2017-11-01

ARL-TR-8225 ● NOV 2017 US Army Research Laboratory Methodology for Designing and Developing a New Ultra-Wideband Antenna Based...Research Laboratory Methodology for Designing and Developing a New Ultra-Wideband Antenna Based on Bio-Inspired Optimization Techniques by...SUBTITLE Methodology for Designing and Developing a New Ultra-Wideband Antenna Based on Bio-Inspired Optimization Techniques 5a. CONTRACT NUMBER

Bio-Inspired Metal-Coordination Dynamics: A Unique Tool for Engineering Soft Matter Mechanics

NASA Astrophysics Data System (ADS)

Holten-Andersen, Niels

Growing evidence supports a critical role of metal-coordination in soft biological material properties such as self-healing, underwater adhesion and autonomous wound plugging. Using bio-inspired metal-binding polymers, initial efforts to mimic these properties with metal-coordination crosslinked polymer materials have shown promise. In addition, with polymer network mechanics strongly coupled to coordinate crosslink dynamics material properties can be easily tuned from visco-elastic fluids to solids. Given their exploitation in desirable material applications in Nature, bio-inspired metal-coordinate complex crosslinking provides an opportunity to further advance synthetic polymer materials design. Early lessons from this pursuit are presented.

Bio-inspired hydrophobic modification of cellulose nanocrystals with castor oil.

PubMed

Shang, Qianqian; Liu, Chengguo; Hu, Yun; Jia, Puyou; Hu, Lihong; Zhou, Yonghong

2018-07-01

This work presents an efficient and environmentally friendly approach to generate hydrophobic cellulose nanocrystals (CNC) using thiol-containing castor oil (CO-SH) as a renewable hydrophobe with the assist of bio-inspired dopamine at room temperature. The modification process included the formation of the polydopamine (PDA) buffer layer on CNC surfaces and the Michael addition reaction between the catechol moieties of PDA coating and thiol groups of CO-SH. The morphology, crystalline structure, surface chemistry, thermal stability and hydrophobicity of the modified CNC were charactered by TEM, XRD, FT-IR, solid-state 13 C NMR, XPS, TGA and contact angle analysis. The modified CNC preserved cellulose crystallinity, displayed higher thermal stability than unmodified CNC, and was highly hydrophobic with a water contact angle of 95.6°. The simplicity and versatility of the surface modification strategy inspired by adhesive protein of mussel may promote rapid development of hydrophobic bio-based nanomaterials for various applications. Copyright © 2018 Elsevier Ltd. All rights reserved.

Bio-inspired color sketch for eco-friendly printing

NASA Astrophysics Data System (ADS)

Safonov, Ilia V.; Tolstaya, Ekaterina V.; Rychagov, Michael N.; Lee, Hokeun; Kim, Sang Ho; Choi, Donchul

2012-01-01

Saving of toner/ink consumption is an important task in modern printing devices. It has a positive ecological and social impact. We propose technique for converting print-job pictures to a recognizable and pleasant color sketches. Drawing a "pencil sketch" from a photo relates to a special area in image processing and computer graphics - non-photorealistic rendering. We describe a new approach for automatic sketch generation which allows to create well-recognizable sketches and to preserve partly colors of the initial picture. Our sketches contain significantly less color dots then initial images and this helps to save toner/ink. Our bio-inspired approach is based on sophisticated edge detection technique for a mask creation and multiplication of source image with increased contrast by this mask. To construct the mask we use DoG edge detection, which is a result of blending of initial image with its blurred copy through the alpha-channel, which is created from Saliency Map according to Pre-attentive Human Vision model. Measurement of percentage of saved toner and user study proves effectiveness of proposed technique for toner saving in eco-friendly printing mode.

A bio-molecular inspired electronic architecture: bio-based device concepts for enhanced sensing (Invited Paper)

NASA Astrophysics Data System (ADS)

Woolard, Dwight L.; Luo, Ying; Gelmont, Boris L.; Globus, Tatiana; Jensen, James O.

2005-05-01

A biological(bio)-molecular inspired electronic architecture is presented that offers the potential for defining nanoscale sensor platforms with enhanced capabilities for sensing terahertz (THz) frequency bio-signatures. This architecture makes strategic use of integrated biological elements to enable communication and high-level function within densely-packed nanoelectronic systems. In particular, this architecture introduces a new paradigm for establishing hybrid Electro-THz-Optical (ETO) communication channels where the THz-frequency spectral characteristics that are uniquely associated with the embedded bio-molecules are utilized directly. Since the functionality of this architecture is built upon the spectral characteristics of bio-molecules, this immediately allows for defining new methods for enhanced sensing of THz bio-signatures. First, this integrated sensor concept greatly facilitates the collection of THz bio-signatures associated with embedded bio-molecules via interactions with the time-dependent signals propagating through the nanoelectronic circuit. Second, it leads to a new Multi-State Spectral Sensing (MS3) approach where bio-signature information can be collected from multiple metastable state conformations. This paper will also introduce a new class of prototype devices that utilize THz-sensitive bio-molecules to achieve molecular-level sensing and functionality. Here, new simulation results are presented for a class of bio-molecular components that exhibit the prescribed type of ETO characteristics required for realizing integrated sensor platforms. Most noteworthy, this research derives THz spectral bio-signatures for organic molecules that are amenable to photo-induced metastable-state conformations and establishes an initial scientific foundation and design blueprint for an enhanced THz bio-signature sensing capability.

Vibro-Perception of Optical Bio-Inspired Fiber-Skin.

PubMed

Li, Tao; Zhang, Sheng; Lu, Guo-Wei; Sunami, Yuta

2018-05-12

In this research, based on the principle of optical interferometry, the Mach-Zehnder and Optical Phase-locked Loop (OPLL) vibro-perception systems of bio-inspired fiber-skin are designed to mimic the tactile perception of human skin. The fiber-skin is made of the optical fiber embedded in the silicone elastomer. The optical fiber is an instinctive and alternative sensor for tactile perception with high sensitivity and reliability, also low cost and susceptibility to the magnetic interference. The silicone elastomer serves as a substrate with high flexibility and biocompatibility, and the optical fiber core serves as the vibro-perception sensor to detect physical motions like tapping and sliding. According to the experimental results, the designed optical fiber-skin demonstrates the ability to detect the physical motions like tapping and sliding in both the Mach-Zehnder and OPLL vibro-perception systems. For direct contact condition, the OPLL vibro-perception system shows better performance compared with the Mach-Zehnder vibro-perception system. However, the Mach-Zehnder vibro-perception system is preferable to the OPLL system in the indirect contact experiment. In summary, the fiber-skin is validated to have light touch character and excellent repeatability, which is highly-suitable for skin-mimic sensing.

Overcoming the brittleness of glass through bio-inspiration and micro-architecture.

PubMed

Mirkhalaf, M; Dastjerdi, A Khayer; Barthelat, F

2014-01-01

Highly mineralized natural materials such as teeth or mollusk shells boast unusual combinations of stiffness, strength and toughness currently unmatched by engineering materials. While high mineral contents provide stiffness and hardness, these materials also contain weaker interfaces with intricate architectures, which can channel propagating cracks into toughening configurations. Here we report the implementation of these features into glass, using a laser engraving technique. Three-dimensional arrays of laser-generated microcracks can deflect and guide larger incoming cracks, following the concept of 'stamp holes'. Jigsaw-like interfaces, infiltrated with polyurethane, furthermore channel cracks into interlocking configurations and pullout mechanisms, significantly enhancing energy dissipation and toughness. Compared with standard glass, which has no microstructure and is brittle, our bio-inspired glass displays built-in mechanisms that make it more deformable and 200 times tougher. This bio-inspired approach, based on carefully architectured interfaces, provides a new pathway to toughening glasses, ceramics or other hard and brittle materials.

Overcoming the brittleness of glass through bio-inspiration and micro-architecture

NASA Astrophysics Data System (ADS)

Mirkhalaf, M.; Dastjerdi, A. Khayer; Barthelat, F.

2014-01-01

Highly mineralized natural materials such as teeth or mollusk shells boast unusual combinations of stiffness, strength and toughness currently unmatched by engineering materials. While high mineral contents provide stiffness and hardness, these materials also contain weaker interfaces with intricate architectures, which can channel propagating cracks into toughening configurations. Here we report the implementation of these features into glass, using a laser engraving technique. Three-dimensional arrays of laser-generated microcracks can deflect and guide larger incoming cracks, following the concept of ‘stamp holes’. Jigsaw-like interfaces, infiltrated with polyurethane, furthermore channel cracks into interlocking configurations and pullout mechanisms, significantly enhancing energy dissipation and toughness. Compared with standard glass, which has no microstructure and is brittle, our bio-inspired glass displays built-in mechanisms that make it more deformable and 200 times tougher. This bio-inspired approach, based on carefully architectured interfaces, provides a new pathway to toughening glasses, ceramics or other hard and brittle materials.

A Review on Development and Applications of Bio-Inspired Superhydrophobic Textiles

PubMed Central

Ahmad, Ishaq; Kan, Chi-wai

2016-01-01

Bio-inspired engineering has been envisioned in a wide array of applications. All living bodies on Earth, including animals and plants, have well organized functional systems developed by nature. These naturally designed functional systems inspire scientists and engineers worldwide to mimic the system for practical applications by human beings. Researchers in the academic world and industries have been trying, for hundreds of years, to demonstrate how these natural phenomena could be translated into the real world to save lives, money and time. One of the most fascinating natural phenomena is the resistance of living bodies to contamination by dust and other pollutants, thus termed as self-cleaning phenomenon. This phenomenon has been observed in many plants, animals and insects and is termed as the Lotus Effect. With advancement in research and technology, attention has been given to the exploration of the underlying mechanisms of water repellency and self-cleaning. As a result, various concepts have been developed including Young’s equation, and Wenzel and Cassie–Baxter theories. The more we unravel this process, the more we get access to its implications and applications. A similar pursuit is emphasized in this review to explain the fundamental principles, mechanisms, past experimental approaches and ongoing research in the development of bio-inspired superhydrophobic textiles. PMID:28774012

Control of Flow Structure on Non-Slender Delta Wing: Bio-inspired Edge Modifications, Passive Bleeding, and Pulsed Blowing

NASA Astrophysics Data System (ADS)

Yavuz, Mehmet Metin; Celik, Alper; Cetin, Cenk

2016-11-01

In the present study, different flow control approaches including bio-inspired edge modifications, passive bleeding, and pulsed blowing are introduced and applied for the flow over non-slender delta wing. Experiments are conducted in a low speed wind tunnel for a 45 degree swept delta wing using qualitative and quantitative measurement techniques including laser illuminated smoke visualization, particle image velocimety (PIV), and surface pressure measurements. For the bio-inspired edge modifications, the edges of the wing are modified to dolphin fluke geometry. In addition, the concept of flexion ratio, a ratio depending on the flexible length of animal propulsors such as wings, is introduced. For passive bleeding, directing the free stream air from the pressure side of the planform to the suction side of the wing is applied. For pulsed blowing, periodic air injection through the leading edge of the wing is performed in a square waveform with 25% duty cycle at different excitation frequencies and compared with the steady and no blowing cases. The results indicate that each control approach is quite effective in terms of altering the overall flow structure on the planform. However, the success level, considering the elimination of stall or delaying the vortex breakdown, depends on the parameters in each method.

Multiplexed BioCD for prostate specific antigen detection

NASA Astrophysics Data System (ADS)

Wang, Xuefeng; Zhao, Ming; Nolte, David D.

2008-02-01

Specific protein concentrations in human body fluid can serve as diagnostic markers for some diseases, and a quantitative and high-throughput technique for multiplexed protein detection would speed up diagnosis and facilitate medical research. For this purpose, our group developed the BioCD, a spinning-disc interferometric biosensor on which antibody is immobilized. The detection system adopts a common-path scheme making it ultra stable. The scaling mass sensitivity is below 10 pg/mm for protein surface density. A 25000-spot antibody BioCD was fabricated to measure the concentration of prostate specific antigen (PSA), a protein indicating prostate cancer if its level is high. Statistical analysis of our immunoassay results projects that the detection limit of PSA would reach 20 pg/ml in a 2 mg/ml background solution. For future prospects, a multiplexed BioCD can be produced for simultaneous diagnosis of diverse diseases. For instance, 100 markers above 200 pg/ml could be measured on a single disc given that the detection limit is inversely proportional to square root of the number of spots.

On-chip visual perception of motion: a bio-inspired connectionist model on FPGA.

PubMed

Torres-Huitzil, César; Girau, Bernard; Castellanos-Sánchez, Claudio

2005-01-01

Visual motion provides useful information to understand the dynamics of a scene to allow intelligent systems interact with their environment. Motion computation is usually restricted by real time requirements that need the design and implementation of specific hardware architectures. In this paper, the design of hardware architecture for a bio-inspired neural model for motion estimation is presented. The motion estimation is based on a strongly localized bio-inspired connectionist model with a particular adaptation of spatio-temporal Gabor-like filtering. The architecture is constituted by three main modules that perform spatial, temporal, and excitatory-inhibitory connectionist processing. The biomimetic architecture is modeled, simulated and validated in VHDL. The synthesis results on a Field Programmable Gate Array (FPGA) device show the potential achievement of real-time performance at an affordable silicon area.

Bio-inspired evaporation through plasmonic film of nanoparticles at the air-water interface.

PubMed

Wang, Zhenhui; Liu, Yanming; Tao, Peng; Shen, Qingchen; Yi, Nan; Zhang, Fangyu; Liu, Quanlong; Song, Chengyi; Zhang, Di; Shang, Wen; Deng, Tao

2014-08-27

Plasmonic gold nanoparticles self-assembled at the air-water interface to produce an evaporative surface with local control inspired by skins and plant leaves. Fast and efficient evaporation is realized due to the instant and localized plasmonic heating at the evaporative surface. The bio-inspired evaporation process provides an alternative promising approach for evaporation, and has potential applications in sterilization, distillation, and heat transfer. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Light and colour as analytical detection tools: a journey into the periodic table using polyamines to bio-inspired systems as chemosensors.

PubMed

Lodeiro, Carlos; Capelo, José Luis; Mejuto, Juan Carlos; Oliveira, Elisabete; Santos, Hugo M; Pedras, Bruno; Nuñez, Cristina

2010-08-01

This critical review describes some developments on the chemistry of fluorescent and colorimetric molecular probes or chemosensors, based on polyamines and associated compounds having oxygen and/or sulfur as donor atoms. The reported systems are essentially based on some selected published work in this field in the last five years, and in the work developed by the authors from 2000 onwards. Some interesting properties beyond sensing molecules, ions or/and cations by fluorescence, colorimetry as well as by MALDI-TOF MS spectrometry can arise from these systems. A short brief on different examples activated by PET (photoinduced electron transfer), ICT (internal charge transfer) and EET (electronic energy transfer) phenomena will be provided. Finally the introduction of bio-inspired compounds derived from emissive amino acid or short peptide systems and nanoparticle devices to detect metal ions will be reviewed (202 references).

Interactive Learning Environment for Bio-Inspired Optimization Algorithms for UAV Path Planning

ERIC Educational Resources Information Center

Duan, Haibin; Li, Pei; Shi, Yuhui; Zhang, Xiangyin; Sun, Changhao

2015-01-01

This paper describes the development of BOLE, a MATLAB-based interactive learning environment, that facilitates the process of learning bio-inspired optimization algorithms, and that is dedicated exclusively to unmanned aerial vehicle path planning. As a complement to conventional teaching methods, BOLE is designed to help students consolidate the…

Bio-inspired synthetic receptor molecules towards mimicry of vancomycin.

PubMed

Monnee, M C; Brouwer, A J; Verbeek, L M; van Wageningen, A M; Liskamp, R M

2001-06-18

A 512-member library of bio-inspired synthetic receptor molecules was prepared featuring a triazacyclophane scaffold. The purpose of this scaffold was to orient three (identical) peptide 'binding arms' in order to mimic an antibiotic binding cavity as is present in the vancomycin antibiotics. The library was screened with D-Ala-D-Ala and D-Ala-D-Lac containing ligands, which are present in the cell wall precursors of pathogenic bacteria. Screening and validation led to identification of a synthetic receptor capable of binding these ligands.

A two-dimensional iterative panel method and boundary layer model for bio-inspired multi-body wings

NASA Astrophysics Data System (ADS)

Blower, Christopher J.; Dhruv, Akash; Wickenheiser, Adam M.

2014-03-01

The increased use of Unmanned Aerial Vehicles (UAVs) has created a continuous demand for improved flight capabilities and range of use. During the last decade, engineers have turned to bio-inspiration for new and innovative flow control methods for gust alleviation, maneuverability, and stability improvement using morphing aircraft wings. The bio-inspired wing design considered in this study mimics the flow manipulation techniques performed by birds to extend the operating envelope of UAVs through the installation of an array of feather-like panels across the airfoil's upper and lower surfaces while replacing the trailing edge flap. Each flap has the ability to deflect into both the airfoil and the inbound airflow using hinge points with a single degree-of-freedom, situated at 20%, 40%, 60% and 80% of the chord. The installation of the surface flaps offers configurations that enable advantageous maneuvers while alleviating gust disturbances. Due to the number of possible permutations available for the flap configurations, an iterative constant-strength doublet/source panel method has been developed with an integrated boundary layer model to calculate the pressure distribution and viscous drag over the wing's surface. As a result, the lift, drag and moment coefficients for each airfoil configuration can be calculated. The flight coefficients of this numerical method are validated using experimental data from a low speed suction wind tunnel operating at a Reynolds Number 300,000. This method enables the aerodynamic assessment of a morphing wing profile to be performed accurately and efficiently in comparison to Computational Fluid Dynamics methods and experiments as discussed herein.

An Experimental Investigation on Bio-inspired Icephobic Coatings for Aircraft Icing Mitigation

NASA Astrophysics Data System (ADS)

Hu, Hui; Li, Haixing; Waldman, Rye

2016-11-01

By leveraging the Icing Research Tunnel available at Iowa State University (ISU-IRT), a series of experimental investigations were conducted to elucidate the underlying physics pertinent to aircraft icing phenomena. A suite of advanced flow diagnostic techniques, which include high-speed photographic imaging, digital image projection (DIP), and infrared (IR) imaging thermometry, were developed and applied to quantify the transient behavior of water droplet impingement, wind-driven surface water runback, unsteady heat transfer and dynamic ice accreting process over the surfaces of airfoil/wing models. The icephobic performance of various bio-inspired superhydrophobic coatings were evaluated quantitatively at different icing conditions. The findings derived from the icing physics studies can be used to improve current icing accretion models for more accurate prediction of ice formation and accretion on aircraft wings and to develop effective anti-/deicing strategies for safer and more efficient operation of aircraft in cold weather. The research work is partially supported by NASA with Grant Number NNX12AC21A and National Science Foundation under Award Numbers of CBET-1064196 and CBET-1435590.

Bio-inspired control of joint torque and knee stiffness in a robotic lower limb exoskeleton using a central pattern generator.

PubMed

Schrade, Stefan O; Nager, Yannik; Wu, Amy R; Gassert, Roger; Ijspeert, Auke

2017-07-01

Robotic lower limb exoskeletons are becoming increasingly popular in therapy and recreational use. However, most exoskeletons are still rather limited in their locomotion speed and the activities of daily live they can perform. Furthermore, they typically do not allow for a dynamic adaptation to the environment, as they are often controlled with predefined reference trajectories. Inspired by human leg stiffness modulation during walking, variable stiffness actuators increase flexibility without the need for more complex controllers. Actuation with adaptable stiffness is inspired by the human leg stiffness modulation during walking. However, this actuation principle also introduces the stiffness setpoint as an additional degree of freedom that needs to be coordinated with the joint trajectories. As a potential solution to this issue a bio-inspired controller based on a central pattern generator (CPG) is presented in this work. It generates coordinated joint torques and knee stiffness modulations to produce flexible and dynamic gait patterns for an exoskeleton with variable knee stiffness actuation. The CPG controller is evaluated and optimized in simulation using a model of the exoskeleton. The CPG controller produced stable and smooth gait for walking speeds from 0.4 m/s up to 1.57 m/s with a torso stabilizing force that simulated the use of crutches, which are commonly needed by exoskeleton users. Through the CPG, the knee stiffness intrinsically adapted to the frequency and phase of the gait, when the speed was changed. Additionally, it adjusted to changes in the environment in the form of uneven terrain by reacting to ground contact forces. This could allow future exoskeletons to be more adaptive to various environments, thus making ambulation more robust.

A Bio-Inspired Polymeric Gradient Refractive Index (GRIN) Human Eye Lens

DTIC Science & Technology

2012-11-19

confirmation of the desired aspheric surface shape. Furthermore, the wavefronts of aspheric posterior GRIN and PMMA lenses were measured and...compared a homogenous PMMA lens of an identical geometry. Finally, the anterior and posterior GRIN lenses were assembled into a bio-inspired GRIN...topography and exhibited confirmation of the desired aspheric surface shape. Furthermore, the wavefronts of aspheric posterior GRIN and PMMA lenses were

Fluorimetric Mercury Test Strips with Suppressed "Coffee Stains" by a Bio-inspired Fabrication Strategy.

PubMed

Qiao, Yuchun; Shang, Jizhen; Li, Shuying; Feng, Luping; Jiang, Yao; Duan, Zhiqiang; Lv, Xiaoxia; Zhang, Chunxian; Yao, Tiantian; Dong, Zhichao; Zhang, Yu; Wang, Hua

2016-11-04

A fluorimetric Hg 2+ test strip has been developed using a lotus-inspired fabrication method for suppressing the "coffee stains" toward the uniform distribution of probe materials through creating a hydrophobic drying pattern for fast solvent evaporation. The test strips were first loaded with the model probes of fluorescent gold-silver nanoclusters and then dried in vacuum on the hydrophobic pattern. On the one hand, here, the hydrophobic constraining forces from the lotus surface-like pattern could control the exterior transport of dispersed nanoclusters on strips leading to the minimized "coffee stains". On the other hand, the vacuum-aided fast solvent evaporation could boost the interior Marangoni flow of probe materials on strips to expect the further improved probe distribution on strips. High aqueous stability and enhanced fluorescence of probes on test strips were realized by the hydrophilic treatment with amine-derivatized silicane. A test strips-based fluorimetry has thereby been developed for probing Hg 2+ ions in wastewater, showing the detection performances comparable to the classic instrumental analysis ones. Such a facile and efficient fabrication route for the bio-inspired suppression of "coffee stains" on test strips may expand the scope of applications of test strips-based "point-of-care" analysis methods or detection devices in the biomedical and environmental fields.

Aurelia aurita bio-inspired tilt sensor

NASA Astrophysics Data System (ADS)

Smith, Colin; Villanueva, Alex; Priya, Shashank

2012-10-01

The quickly expanding field of mobile robots, unmanned underwater vehicles, and micro-air vehicles urgently needs a cheap and effective means for measuring vehicle inclination. Commonly, tilt or inclination has been mathematically derived from accelerometers; however, there is inherent error in any indirect measurement. This paper reports a bio-inspired tilt sensor that mimics the natural balance organ of jellyfish, called the ‘statocyst’. Biological statocysts from the species Aurelia aurita were characterized by scanning electron microscopy to investigate the morphology and size of the natural sensor. An artificial tilt sensor was then developed by using printed electronics that incorporates a novel voltage divider concept in conjunction with small surface mount devices. This sensor was found to have minimum sensitivity of 4.21° with a standard deviation of 1.77°. These results open the possibility of developing elegant tilt sensor architecture for both air and water based platforms.

Towards a Bio-inspired Security Framework for Mission-Critical Wireless Sensor Networks

NASA Astrophysics Data System (ADS)

Ren, Wei; Song, Jun; Ma, Zhao; Huang, Shiyong

Mission-critical wireless sensor networks (WSNs) have been found in numerous promising applications in civil and military fields. However, the functionality of WSNs extensively relies on its security capability for detecting and defending sophisticated adversaries, such as Sybil, worm hole and mobile adversaries. In this paper, we propose a bio-inspired security framework to provide intelligence-enabled security mechanisms. This scheme is composed of a middleware, multiple agents and mobile agents. The agents monitor the network packets, host activities, make decisions and launch corresponding responses. Middleware performs an infrastructure for the communication between various agents and corresponding mobility. Certain cognitive models and intelligent algorithms such as Layered Reference Model of Brain and Self-Organizing Neural Network with Competitive Learning are explored in the context of sensor networks that have resource constraints. The security framework and implementation are also described in details.

Bio-inspired Autonomic Structures: a middleware for Telecommunications Ecosystems

NASA Astrophysics Data System (ADS)

Manzalini, Antonio; Minerva, Roberto; Moiso, Corrado

Today, people are making use of several devices for communications, for accessing multi-media content services, for data/information retrieving, for processing, computing, etc.: examples are laptops, PDAs, mobile phones, digital cameras, mp3 players, smart cards and smart appliances. One of the most attracting service scenarios for future Telecommunications and Internet is the one where people will be able to browse any object in the environment they live: communications, sensing and processing of data and services will be highly pervasive. In this vision, people, machines, artifacts and the surrounding space will create a kind of computational environment and, at the same time, the interfaces to the network resources. A challenging technological issue will be interconnection and management of heterogeneous systems and a huge amount of small devices tied together in networks of networks. Moreover, future network and service infrastructures should be able to provide Users and Application Developers (at different levels, e.g., residential Users but also SMEs, LEs, ASPs/Web2.0 Service roviders, ISPs, Content Providers, etc.) with the most appropriate "environment" according to their context and specific needs. Operators must be ready to manage such level of complication enabling their latforms with technological advanced allowing network and services self-supervision and self-adaptation capabilities. Autonomic software solutions, enhanced with innovative bio-inspired mechanisms and algorithms, are promising areas of long term research to face such challenges. This chapter proposes a bio-inspired autonomic middleware capable of leveraging the assets of the underlying network infrastructure whilst, at the same time, supporting the development of future Telecommunications and Internet Ecosystems.

Bio-inspired secure data mules for medical sensor network

NASA Astrophysics Data System (ADS)

Muraleedharan, Rajani; Gao, Weihua; Osadciw, Lisa A.

2010-04-01

Medical sensor network consist of heterogeneous nodes, wireless, mobile and wired with varied functionality. The resources at each sensor require to be exploited minimally while sensitive information is sensed and communicated to its access points using secure data mules. In this paper, we analyze the flat architecture, where different functionality and priority information require varied resources forms a non-deterministic polynomial-time hard problem. Hence, a bio-inspired data mule that helps to obtain dynamic multi-objective solution with minimal resource and secure path is applied. The performance of the proposed approach is based on reduced latency, data delivery rate and resource cost.

Gas barrier properties of bio-inspired Laponite-LC polymer hybrid films.

PubMed

Tritschler, Ulrich; Zlotnikov, Igor; Fratzl, Peter; Schlaad, Helmut; Grüner, Simon; Cölfen, Helmut

2016-05-26

Bio-inspired Laponite (clay)-liquid crystal (LC) polymer composite materials with high clay fractions (>80%) and a high level of orientation of the clay platelets, i.e. with structural features similar to the ones found in natural nacre, have been shown to exhibit a promising behavior in the context of reduced oxygen transmission. Key characteristics of these bio-inspired composite materials are their high inorganic content, high level of exfoliation and orientation of the clay platelets, and the use of a LC polymer forming the organic matrix in between the Laponite particles. Each single feature may be beneficial to increase the materials gas barrier property rendering this composite a promising system with advantageous barrier capacities. In this detailed study, Laponite/LC polymer composite coatings with different clay loadings were investigated regarding their oxygen transmission rate. The obtained gas barrier performance was linked to the quality, respective Laponite content and the underlying composite micro- and nanostructure of the coatings. Most efficient oxygen barrier properties were observed for composite coatings with 83% Laponite loading that exhibit a structure similar to sheet-like nacre. Further on, advantageous mechanical properties of these Laponite/LC polymer composites reported previously give rise to a multifunctional composite system.

Bio-inspired synthesis and biological evaluation of a colchicine-related compound library.

PubMed

Nicolaou, K C; Valiulin, Roman A; Pokorski, Jonathan K; Chang, Vicki; Chen, Jason S

2012-06-01

A bio-inspired investigation of the reactions of substrates of type 1 with VOF(3) and PIFA [phenyliodine(III) bis(trifluoroacetate)] led to a collection of colchicine-like compounds 2-5 and related systems. Biological evaluation revealed that some of the synthesized products had significant cytotoxic properties against the colon cancer cell line HT-29. Copyright © 2012 Elsevier Ltd. All rights reserved.

Biomimetic and bio-inspired uses of mollusc shells.

PubMed

Morris, J P; Wang, Y; Backeljau, T; Chapelle, G

2016-06-01

Climate change and ocean acidification are likely to have a profound effect on marine molluscs, which are of great ecological and economic importance. One process particularly sensitive to climate change is the formation of biominerals in mollusc shells. Fundamental research is broadening our understanding of the biomineralization process, as well as providing more informed predictions on the effects of climate change on marine molluscs. Such studies are important in their own right, but their value also extends to applied sciences. Biominerals, organic/inorganic hybrid materials with many remarkable physical and chemical properties, have been studied for decades, and the possibilities for future improved use of such materials for society are widely recognised. This article highlights the potential use of our understanding of the shell biomineralization process in novel bio-inspired and biomimetic applications. It also highlights the potential for the valorisation of shells produced as a by-product of the aquaculture industry. Studying shells and the formation of biominerals will inspire novel functional hybrid materials. It may also provide sustainable, ecologically- and economically-viable solutions to some of the problems created by current human resource exploitation. Copyright © 2016 Elsevier B.V. All rights reserved.

Optical Properties of a Bio-Inspired Gradient Refractive Index Polymer Lens

DTIC Science & Technology

2008-07-21

Optical properties of a bio-inspired gradient refractive index polymer lens G. Beadie,1,* James S. Shirk,1 A. Rosenberg,1 Paul A. Lane,1 E. Fleet,1...of magnitude less than the homogeneous glass lens. ©2008 Optical Society of America OCIS codes: (110.2760) Gradient-index lenses; (160.5470...H. von Helmholtz, A. Gullstrand, J. von Kries, and W. Nagel, Helmholtz’s Treatise on Physiological Optics (The Optical Society of America, Rochester

A bio-inspired N-doped porous carbon electrocatalyst with hierarchical superstructure for efficient oxygen reduction reaction

NASA Astrophysics Data System (ADS)

Miao, Yue-E.; Yan, Jiajie; Ouyang, Yue; Lu, Hengyi; Lai, Feili; Wu, Yue; Liu, Tianxi

2018-06-01

The bio-inspired hierarchical "grape cluster" superstructure provides an effective integration of one-dimensional carbon nanofibers (CNF) with isolated carbonaceous nanoparticles into three-dimensional (3D) conductive frameworks for efficient electron and mass transfer. Herein, a 3D N-doped porous carbon electrocatalyst consisting of carbon nanofibers with grape-like N-doped hollow carbon particles (CNF@NC) has been prepared through a simple electrospinning strategy combined with in-situ growth and carbonization processes. Such a bio-inspired hierarchically organized conductive network largely facilitates both the mass diffusion and electron transfer during the oxygen reduction reactions (ORR). Therefore, the metal-free CNF@NC catalyst demonstrates superior catalytic activity with an absolute four-electron transfer mechanism, strong methanol tolerance and good long-term stability towards ORR in alkaline media.

Bio-inspired, large scale, highly-scattering films for nanoparticle-alternative white surfaces

PubMed Central

Syurik, Julia; Siddique, Radwanul Hasan; Dollmann, Antje; Gomard, Guillaume; Schneider, Marc; Worgull, Matthias; Wiegand, Gabriele; Hölscher, Hendrik

2017-01-01

Inspired by the white beetle of the genus Cyphochilus, we fabricate ultra-thin, porous PMMA films by foaming with CO2 saturation. Optimising pore diameter and fraction in terms of broad-band reflectance results in very thin films with exceptional whiteness. Already films with 60 µm-thick scattering layer feature a whiteness with a reflectance of 90%. Even 9 µm thin scattering layers appear white with a reflectance above 57%. The transport mean free path in the artificial films is between 3.5 µm and 4 µm being close to the evolutionary optimised natural prototype. The bio-inspired white films do not lose their whiteness during further shaping, allowing for various applications. PMID:28429805

Bio-inspired, large scale, highly-scattering films for nanoparticle-alternative white surfaces

NASA Astrophysics Data System (ADS)

Syurik, Julia; Siddique, Radwanul Hasan; Dollmann, Antje; Gomard, Guillaume; Schneider, Marc; Worgull, Matthias; Wiegand, Gabriele; Hölscher, Hendrik

2017-04-01

Inspired by the white beetle of the genus Cyphochilus, we fabricate ultra-thin, porous PMMA films by foaming with CO2 saturation. Optimising pore diameter and fraction in terms of broad-band reflectance results in very thin films with exceptional whiteness. Already films with 60 µm-thick scattering layer feature a whiteness with a reflectance of 90%. Even 9 µm thin scattering layers appear white with a reflectance above 57%. The transport mean free path in the artificial films is between 3.5 µm and 4 µm being close to the evolutionary optimised natural prototype. The bio-inspired white films do not lose their whiteness during further shaping, allowing for various applications.

Bio-Inspired Engineering of Exploration Systems

NASA Technical Reports Server (NTRS)

Thakoor, Sanita

2003-01-01

The multidisciplinary concept of "bioinspired engineering of exploration systems" (BEES) is described, which is a guiding principle of the continuing effort to develop biomorphic explorers as reported in a number of articles in the past issues of NASA Tech Briefs. The intent of BEES is to distill from the principles found in successful nature-tested mechanisms of specific crucial functions that are hard to accomplish by conventional methods but that are accomplished rather deftly in nature by biological organisms. The intent is not just to mimic operational mechanisms found in a specific biological organism but to imbibe the salient principles from a variety of diverse bio-organisms for the desired crucial function. Thereby, we can build explorer systems that have specific capabilities endowed beyond nature, as they will possess a combination of the best nature-tested mechanisms for that particular function. The approach consists of selecting a crucial function, for example, flight or some selected aspects of flight, and develop an explorer that combines the principles of those specific attributes as seen in diverse flying species into one artificial entity. This will allow going beyond biology and achieving unprecedented capability and adaptability needed in encountering and exploring what is as yet unknown. A classification of biomorphic flyers into two main classes of surface and aerial explorers is illustrated in the figure, with examples of a variety of biological organisms that provide the inspiration in each respective subclass. Such biomorphic explorers may possess varied mobility modes: surface-roving, burrowing, hopping, hovering, or flying, to accomplish surface, subsurface, and aerial exploration. Preprogrammed for a specific function, they could serve as one-way communicating beacons, spread over the exploration site, autonomously looking for/at the targets of interest. In a hierarchical organization, these biomorphic explorers would report to the next

Natural and bio-inspired underwater adhesives: Current progress and new perspectives

NASA Astrophysics Data System (ADS)

Cui, Mengkui; Ren, Susu; Wei, Shicao; Sun, Chengjun; Zhong, Chao

2017-11-01

Many marine organisms harness diverse protein molecules as underwater adhesives to achieve strong and robust interfacial adhesion under dynamic and turbulent environments. Natural underwater adhesion phenomena thus provide inspiration for engineering adhesive materials that can perform in water or high-moisture settings for biomedical and industrial applications. Here we review examples of biological adhesives to show the molecular features of natural adhesives and discuss how such knowledge serves as a heuristic guideline for the rational design of biologically inspired underwater adhesives. In view of future bio-inspired research, we propose several potential opportunities, either in improving upon current L-3, 4-dihydroxyphenylalanine-based and coacervates-enabled adhesives with new features or engineering conceptually new types of adhesives that recapitulate important characteristics of biological adhesives. We underline the importance of viewing natural adhesives as dynamic materials, which owe their outstanding performance to the cellular coordination of protein expression, delivery, deposition, assembly, and curing of corresponding components with spatiotemporal control. We envision that the emerging synthetic biology techniques will provide great opportunities for advancing both fundamental and application aspects of underwater adhesives.

A bio-inspired flying robot sheds light on insect piloting abilities.

PubMed

Franceschini, Nicolas; Ruffier, Franck; Serres, Julien

2007-02-20

When insects are flying forward, the image of the ground sweeps backward across their ventral viewfield and forms an "optic flow," which depends on both the groundspeed and the groundheight. To explain how these animals manage to avoid the ground by using this visual motion cue, we suggest that insect navigation hinges on a visual-feedback loop we have called the optic-flow regulator, which controls the vertical lift. To test this idea, we built a micro-helicopter equipped with an optic-flow regulator and a bio-inspired optic-flow sensor. This fly-by-sight micro-robot can perform exacting tasks such as take-off, level flight, and landing. Our control scheme accounts for many hitherto unexplained findings published during the last 70 years on insects' visually guided performances; for example, it accounts for the fact that honeybees descend in a headwind, land with a constant slope, and drown when travelling over mirror-smooth water. Our control scheme explains how insects manage to fly safely without any of the instruments used onboard aircraft to measure the groundheight, groundspeed, and descent speed. An optic-flow regulator is quite simple in terms of its neural implementation and just as appropriate for insects as it would be for aircraft.

Robot Deception and Squirrel Behavior: A Case Study in Bio-inspired Robotics

DTIC Science & Technology

2014-08-01

employed by doctors/ nurses among others. It is important to focus on this aspect when we consider a robot’s deceptive capabilities in human- robot ... Robot Deception and Squirrel Behavior: A Case Study in Bio-inspired Robotics Jaeeun Shim and Ronald C. Arkin Mobile Robot ...Abstract A common behavior in animals and human beings is deception. Deceptive behavior in robotics is potentially beneficial in several domains

Bio-inspired Fabrication of Complex Hierarchical Structure in Silicon.

PubMed

Gao, Yang; Peng, Zhengchun; Shi, Tielin; Tan, Xianhua; Zhang, Deqin; Huang, Qiang; Zou, Chuanping; Liao, Guanglan

2015-08-01

In this paper, we developed a top-down method to fabricate complex three dimensional silicon structure, which was inspired by the hierarchical micro/nanostructure of the Morpho butterfly scales. The fabrication procedure includes photolithography, metal masking, and both dry and wet etching techniques. First, microscale photoresist grating pattern was formed on the silicon (111) wafer. Trenches with controllable rippled structures on the sidewalls were etched by inductively coupled plasma reactive ion etching Bosch process. Then, Cr film was angled deposited on the bottom of the ripples by electron beam evaporation, followed by anisotropic wet etching of the silicon. The simple fabrication method results in large scale hierarchical structure on a silicon wafer. The fabricated Si structure has multiple layers with uniform thickness of hundreds nanometers. We conducted both light reflection and heat transfer experiments on this structure. They exhibited excellent antireflection performance for polarized ultraviolet, visible and near infrared wavelengths. And the heat flux of the structure was significantly enhanced. As such, we believe that these bio-inspired hierarchical silicon structure will have promising applications in photovoltaics, sensor technology and photonic crystal devices.

Biophysics and Thermodynamics: The Scientific Building Blocks of Bio-inspired Drug Delivery Nano Systems.

PubMed

Demetzos, Costas

2015-06-01

Biophysics and thermodynamics are considered as the scientific milestones for investigating the properties of materials. The relationship between the changes of temperature with the biophysical variables of biomaterials is important in the process of the development of drug delivery systems. Biophysics is a challenge sector of physics and should be used complementary with the biochemistry in order to discover new and promising technological platforms (i.e., drug delivery systems) and to disclose the 'silence functionality' of bio-inspired biological and artificial membranes. Thermal analysis and biophysical approaches in pharmaceuticals present reliable and versatile tools for their characterization and for the successful development of pharmaceutical products. The metastable phases of self-assembled nanostructures such as liposomes should be taken into consideration because they represent the thermal events can affect the functionality of advanced drug delivery nano systems. In conclusion, biophysics and thermodynamics are characterized as the building blocks for design and development of bio-inspired drug delivery systems.

Epoxy composites coating with Fe3O4 decorated graphene oxide: Modified bio-inspired surface chemistry, synergistic effect and improved anti-corrosion performance

NASA Astrophysics Data System (ADS)

Zhan, Yingqing; Zhang, Jieming; Wan, Xinyi; Long, Zhihang; He, Shuangjiang; He, Yi

2018-04-01

To obtain graphene or graphene derivatives based epoxy composite coatings with high anti-corrosion performance, the morphology of nanostructures, dispersion, and interfacial adhesion are key factors that need to be considered. We here demonstrated the bio-inspired co-modification of graphene oxide/Fe3O4 hybrid (GO-Fe3O4@ poly (DA+KH550)) and its synergistic effect on the anti-corrosion performance of epoxy coating. For this purpose, graphene oxide/Fe3O4 hybrid obtained from hydrothermal route was modified by self-polymerization between dopamine and secondary functional monomer (KH550), which led to the modified bio-inspired surface functionalization. This novel modified bio-inspired functionalization was quite distinct from conventional surface modification or decoration. Namely, abundant amino groups were introduced by modified bio-inspired functionalization, which allowed the graphene oxide/Fe3O4 hybrid to disperse well in epoxy resin and enhanced the interfacial adhesion between modified nanofiller and epoxy resin through chemical crosslinking reaction. The electrochemical impedance spectroscopy (EIS) test revealed that anti-corrosive performance of epoxy coatings was significantly enhanced by addition of 0.5 wt% modified bio-inspired functionalized GO-Fe3O4 hybrid compared with neat epoxy and other nanofillers/epoxy composite coatings. Moreover, the micro-hardness of epoxy coating was enhanced by 71.8% compared with pure epoxy coating at the same loading content. In addition, the anticorrosion mechanism of GO-Fe3O4@poly (DA+KH550) was tentatively discussed.

RAIN: A Bio-Inspired Communication and Data Storage Infrastructure.

PubMed

Monti, Matteo; Rasmussen, Steen

2017-01-01

We summarize the results and perspectives from a companion article, where we presented and evaluated an alternative architecture for data storage in distributed networks. We name the bio-inspired architecture RAIN, and it offers file storage service that, in contrast with current centralized cloud storage, has privacy by design, is open source, is more secure, is scalable, is more sustainable, has community ownership, is inexpensive, and is potentially faster, more efficient, and more reliable. We propose that a RAIN-style architecture could form the backbone of the Internet of Things that likely will integrate multiple current and future infrastructures ranging from online services and cryptocurrency to parts of government administration.

A Review of Natural Joint Systems and Numerical Investigation of Bio-Inspired GFRP-to-Steel Joints

PubMed Central

Avgoulas, Evangelos I.; Sutcliffe, Michael P. F.

2016-01-01

There are a great variety of joint types used in nature which can inspire engineering joints. In order to design such biomimetic joints, it is at first important to understand how biological joints work. A comprehensive literature review, considering natural joints from a mechanical point of view, was undertaken. This was used to develop a taxonomy based on the different methods/functions that nature successfully uses to attach dissimilar tissues. One of the key methods that nature uses to join dissimilar materials is a transitional zone of stiffness at the insertion site. This method was used to propose bio-inspired solutions with a transitional zone of stiffness at the joint site for several glass fibre reinforced plastic (GFRP) to steel adhesively bonded joint configurations. The transition zone was used to reduce the material stiffness mismatch of the joint parts. A numerical finite element model was used to identify the optimum variation in material stiffness that minimises potential failure of the joint. The best bio-inspired joints showed a 118% increase of joint strength compared to the standard joints. PMID:28773688

A Review of Natural Joint Systems and Numerical Investigation of Bio-Inspired GFRP-to-Steel Joints.

PubMed

Avgoulas, Evangelos I; Sutcliffe, Michael P F

2016-07-12

There are a great variety of joint types used in nature which can inspire engineering joints. In order to design such biomimetic joints, it is at first important to understand how biological joints work. A comprehensive literature review, considering natural joints from a mechanical point of view, was undertaken. This was used to develop a taxonomy based on the different methods/functions that nature successfully uses to attach dissimilar tissues. One of the key methods that nature uses to join dissimilar materials is a transitional zone of stiffness at the insertion site. This method was used to propose bio-inspired solutions with a transitional zone of stiffness at the joint site for several glass fibre reinforced plastic (GFRP) to steel adhesively bonded joint configurations. The transition zone was used to reduce the material stiffness mismatch of the joint parts. A numerical finite element model was used to identify the optimum variation in material stiffness that minimises potential failure of the joint. The best bio-inspired joints showed a 118% increase of joint strength compared to the standard joints.

Soft network composite materials with deterministic and bio-inspired designs

PubMed Central

Jang, Kyung-In; Chung, Ha Uk; Xu, Sheng; Lee, Chi Hwan; Luan, Haiwen; Jeong, Jaewoong; Cheng, Huanyu; Kim, Gwang-Tae; Han, Sang Youn; Lee, Jung Woo; Kim, Jeonghyun; Cho, Moongee; Miao, Fuxing; Yang, Yiyuan; Jung, Han Na; Flavin, Matthew; Liu, Howard; Kong, Gil Woo; Yu, Ki Jun; Rhee, Sang Il; Chung, Jeahoon; Kim, Byunggik; Kwak, Jean Won; Yun, Myoung Hee; Kim, Jin Young; Song, Young Min; Paik, Ungyu; Zhang, Yihui; Huang, Yonggang; Rogers, John A.

2015-01-01

Hard and soft structural composites found in biology provide inspiration for the design of advanced synthetic materials. Many examples of bio-inspired hard materials can be found in the literature; far less attention has been devoted to soft systems. Here we introduce deterministic routes to low-modulus thin film materials with stress/strain responses that can be tailored precisely to match the non-linear properties of biological tissues, with application opportunities that range from soft biomedical devices to constructs for tissue engineering. The approach combines a low-modulus matrix with an open, stretchable network as a structural reinforcement that can yield classes of composites with a wide range of desired mechanical responses, including anisotropic, spatially heterogeneous, hierarchical and self-similar designs. Demonstrative application examples in thin, skin-mounted electrophysiological sensors with mechanics precisely matched to the human epidermis and in soft, hydrogel-based vehicles for triggered drug release suggest their broad potential uses in biomedical devices. PMID:25782446

Simultaneous size control and surface functionalization of titania nanoparticles through bioadhesion-assisted bio-inspired mineralization

NASA Astrophysics Data System (ADS)

Shi, Jiafu; Yang, Dong; Jiang, Zhongyi; Jiang, Yanjun; Liang, Yanpeng; Zhu, Yuanyuan; Wang, Xiaoli; Wang, Huihui

2012-09-01

Simultaneous size control and surface functionalization of inorganic nanoparticles (NPs) are often desired for their efficient applications in (bio)catalysis, drug and/or DNA delivery, and photonics, etc. In this study, a novel strategy "bioadhesion-assisted bio-inspired mineralization (BABM)" was put forward to prepare titania nanoparticles (TiNPs) with tunable particle size and multiple surface functionality. Specifically, the initial formation and subsequent growth of TiNPs were enabled by arginine via bio-inspired mineralization, while the mineralization process was terminated through the addition of the pre-polymerized dopa (oligodopa). By adjusting the addition time of oligodopa, the size of TiNPs could be facilely tailored from ca. 30-350 nm; meanwhile, the surface of TiNPs could be functionalized by oligodopa through metal-catechol coordination interaction (a typical bioadhesion phenomenon). In other words, oligodopa coating could not only exquisitely control the size of TiNPs, but also render TiNPs surface multifunctional groups for secondary treatment such as conjugating proteins through amine-catechol adduct formation. Hopefully, this BABM approach will construct a versatile platform for green and facile synthesis of inorganic NPs, in particular transition metal oxide NPs.

Bio-inspired patterned networks (BIPS) for development of wearable/disposable biosensors

NASA Astrophysics Data System (ADS)

McLamore, E. S.; Convertino, M.; Hondred, John; Das, Suprem; Claussen, J. C.; Vanegas, D. C.; Gomes, C.

2016-05-01

Here we demonstrate a novel approach for fabricating point of care (POC) wearable electrochemical biosensors based on 3D patterning of bionanocomposite networks. To create Bio-Inspired Patterned network (BIPS) electrodes, we first generate fractal network in silico models that optimize transport of network fluxes according to an energy function. Network patterns are then inkjet printed onto flexible substrate using conductive graphene ink. We then deposit fractal nanometal structures onto the graphene to create a 3D nanocomposite network. Finally, we biofunctionalize the surface with biorecognition agents using covalent bonding. In this paper, BIPS are used to develop high efficiency, low cost biosensors for measuring glucose as a proof of concept. Our results on the fundamental performance of BIPS sensors show that the biomimetic nanostructures significantly enhance biosensor sensitivity, accuracy, response time, limit of detection, and hysteresis compared to conventional POC non fractal electrodes (serpentine, interdigitated, and screen printed electrodes). BIPs, in particular Apollonian patterned BIPS, represent a new generation of POC biosensors based on nanoscale and microscale fractal networks that significantly improve electrical connectivity, leading to enhanced sensor performance.

System impairment compensation in coherent optical communications by using a bio-inspired detector based on artificial neural network and genetic algorithm

NASA Astrophysics Data System (ADS)

Wang, Danshi; Zhang, Min; Li, Ze; Song, Chuang; Fu, Meixia; Li, Jin; Chen, Xue

2017-09-01

A bio-inspired detector based on the artificial neural network (ANN) and genetic algorithm is proposed in the context of a coherent optical transmission system. The ANN is designed to mitigate 16-quadrature amplitude modulation system impairments, including linear impairment: Gaussian white noise, laser phase noise, in-phase/quadrature component imbalance, and nonlinear impairment: nonlinear phase. Without prior information or heuristic assumptions, the ANN, functioning as a machine learning algorithm, can learn and capture the characteristics of impairments from observed data. Numerical simulations were performed, and dispersion-shifted, dispersion-managed, and dispersion-unmanaged fiber links were investigated. The launch power dynamic range and maximum transmission distance for the bio-inspired method were 2.7 dBm and 240 km greater, respectively, than those of the maximum likelihood estimation algorithm. Moreover, the linewidth tolerance of the bio-inspired technique was 170 kHz greater than that of the k-means method, demonstrating its usability for digital signal processing in coherent systems.

Bio-inspired multistructured conical copper wires for highly efficient liquid manipulation.

PubMed

Wang, Qianbin; Meng, Qingan; Chen, Ming; Liu, Huan; Jiang, Lei

2014-09-23

Animal hairs are typical structured conical fibers ubiquitous in natural system that enable the manipulation of low viscosity liquid in a well-controlled manner, which serves as the fundamental structure in Chinese brush for ink delivery in a controllable manner. Here, drawing inspiration from these structure, we developed a dynamic electrochemical method that enables fabricating the anisotropic multiscale structured conical copper wire (SCCW) with controllable conicity and surface morphology. The as-prepared SCCW exhibits a unique ability for manipulating liquid with significantly high efficiency, and over 428 times greater than its own volume of liquid could be therefore operated. We propose that the boundary condition of the dynamic liquid balance behavior on conical fibers, namely, steady holding of liquid droplet at the tip region of the SCCW, makes it an excellent fibrous medium to manipulate liquid. Moreover, we demonstrate that the titling angle of the SCCW can also affect its efficiency of liquid manipulation by virtue of its mechanical rigidity, which is hardly realized by flexible natural hairs. We envision that the bio-inspired SCCW could give inspiration in designing materials and devices to manipulate liquid in a more controllable way and with high efficiency.

Fluorimetric Mercury Test Strips with Suppressed “Coffee Stains” by a Bio-inspired Fabrication Strategy

PubMed Central

Qiao, Yuchun; Shang, Jizhen; Li, Shuying; Feng, Luping; Jiang, Yao; Duan, Zhiqiang; Lv, Xiaoxia; Zhang, Chunxian; Yao, Tiantian; Dong, Zhichao; Zhang, Yu; Wang, Hua

2016-01-01

A fluorimetric Hg2+ test strip has been developed using a lotus-inspired fabrication method for suppressing the “coffee stains” toward the uniform distribution of probe materials through creating a hydrophobic drying pattern for fast solvent evaporation. The test strips were first loaded with the model probes of fluorescent gold-silver nanoclusters and then dried in vacuum on the hydrophobic pattern. On the one hand, here, the hydrophobic constraining forces from the lotus surface-like pattern could control the exterior transport of dispersed nanoclusters on strips leading to the minimized “coffee stains”. On the other hand, the vacuum-aided fast solvent evaporation could boost the interior Marangoni flow of probe materials on strips to expect the further improved probe distribution on strips. High aqueous stability and enhanced fluorescence of probes on test strips were realized by the hydrophilic treatment with amine-derivatized silicane. A test strips-based fluorimetry has thereby been developed for probing Hg2+ ions in wastewater, showing the detection performances comparable to the classic instrumental analysis ones. Such a facile and efficient fabrication route for the bio-inspired suppression of “coffee stains” on test strips may expand the scope of applications of test strips-based “point-of-care” analysis methods or detection devices in the biomedical and environmental fields. PMID:27812040

A new bio-inspired optimisation algorithm: Bird Swarm Algorithm

NASA Astrophysics Data System (ADS)

Meng, Xian-Bing; Gao, X. Z.; Lu, Lihua; Liu, Yu; Zhang, Hengzhen

2016-07-01

A new bio-inspired algorithm, namely Bird Swarm Algorithm (BSA), is proposed for solving optimisation applications. BSA is based on the swarm intelligence extracted from the social behaviours and social interactions in bird swarms. Birds mainly have three kinds of behaviours: foraging behaviour, vigilance behaviour and flight behaviour. Birds may forage for food and escape from the predators by the social interactions to obtain a high chance of survival. By modelling these social behaviours, social interactions and the related swarm intelligence, four search strategies associated with five simplified rules are formulated in BSA. Simulations and comparisons based on eighteen benchmark problems demonstrate the effectiveness, superiority and stability of BSA. Some proposals for future research about BSA are also discussed.

Optimized bio-inspired stiffening design for an engine nacelle.

PubMed

Lazo, Neil; Vodenitcharova, Tania; Hoffman, Mark

2015-11-04

Structural efficiency is a common engineering goal in which an ideal solution provides a structure with optimized performance at minimized weight, with consideration of material mechanical properties, structural geometry, and manufacturability. This study aims to address this goal in developing high performance lightweight, stiff mechanical components by creating an optimized design from a biologically-inspired template. The approach is implemented on the optimization of rib stiffeners along an aircraft engine nacelle. The helical and angled arrangements of cellulose fibres in plants were chosen as the bio-inspired template. Optimization of total displacement and weight was carried out using a genetic algorithm (GA) coupled with finite element analysis. Iterations showed a gradual convergence in normalized fitness. Displacement was given higher emphasis in optimization, thus the GA optimization tended towards individual designs with weights near the mass constraint. Dominant features of the resulting designs were helical ribs with rectangular cross-sections having large height-to-width ratio. Displacement reduction was at 73% as compared to an unreinforced nacelle, and is attributed to the geometric features and layout of the stiffeners, while mass is maintained within the constraint.

A tracked robot with novel bio-inspired passive "legs".

PubMed

Sun, Bo; Jing, Xingjian

2017-01-01

For track-based robots, an important aspect is the suppression design, which determines the trafficability and comfort of the whole system. The trafficability limits the robot's working capability, and the riding comfort limits the robot's working effectiveness, especially with some sensitive instruments mounted on or operated. To these aims, a track-based robot equipped with a novel passive bio-inspired suspension is designed and studied systematically in this paper. Animal or insects have very special leg or limb structures which are good for motion control and adaptable to different environments. Inspired by this, a new track-based robot is designed with novel "legs" for connecting the loading wheels to the robot body. Each leg is designed with passive structures and can achieve very high loading capacity but low dynamic stiffness such that the robot can move on rough ground similar to a multi-leg animal or insect. Therefore, the trafficability and riding comfort can be significantly improved without losing loading capacity. The new track-based robot can be well applied to various engineering tasks for providing a stable moving platform of high mobility, better trafficability and excellent loading capacity.

Bio-inspired piezoelectric linear motor driven by a single-phase harmonic wave with an asymmetric stator.

PubMed

Pan, Qiaosheng; Miao, Enming; Wu, Bingxuan; Chen, Weikang; Lei, Xiujun; He, Liangguo

2017-07-01

A novel, bio-inspired, single-phase driven piezoelectric linear motor (PLM) using an asymmetric stator was designed, fabricated, and tested to avoid mode degeneracy and to simplify the drive mechanism of a piezoelectric motor. A piezoelectric transducer composed of two piezoelectric stacks and a displacement amplifier was used as the driving element of the PLM. Two simple and specially designed claws performed elliptical motion. A numerical simulation was performed to design the stator and determine the feasibility of the design mechanism of the PLM. Moreover, an experimental setup was built to validate the working principles, as well as to evaluate the performance, of the PLM. The prototype motor outputs a no-load speed of 233.7 mm/s at a voltage of 180 V p-p and a maximum thrust force of 2.3 N under a preload of 10 N. This study verified the feasibility of the proposed design and provided a method to simplify the driving harmonic signal and structure of PLMs.

Balancing Human and Inter-Agent Influences for Shared Control of Bio-Inspired Collectives

DTIC Science & Technology

2014-10-01

the higher-level intelligence and ingenuity of a human operator as well as the collective intelligence and robustness of a bio-inspired collective...for reducing this burden, to Washington Headquarters Services, Directorate for Information Operations and Reports, 1215 Jefferson Davis Highway...agents, or that receive information from, but are not directly controlled by, a human operator . Unlike, agents in the human-controlled partition, agents

Final Report for Bio-Inspired Approaches to Moving-Target Defense Strategies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fink, Glenn A.; Oehmen, Christopher S.

This report records the work and contributions of the NITRD-funded Bio-Inspired Approaches to Moving-Target Defense Strategies project performed by Pacific Northwest National Laboratory under the technical guidance of the National Security Agency’s R6 division. The project has incorporated a number of bio-inspired cyber defensive technologies within an elastic framework provided by the Digital Ants. This project has created the first scalable, real-world prototype of the Digital Ants Framework (DAF)[11] and integrated five technologies into this flexible, decentralized framework: (1) Ant-Based Cyber Defense (ABCD), (2) Behavioral Indicators, (3) Bioinformatic Clas- sification, (4) Moving-Target Reconfiguration, and (5) Ambient Collaboration. The DAF canmore » be used operationally to decentralize many such data intensive applications that normally rely on collection of large amounts of data in a central repository. In this work, we have shown how these component applications may be decentralized and may perform analysis at the edge. Operationally, this will enable analytics to scale far beyond current limitations while not suffering from the bandwidth or computational limitations of centralized analysis. This effort has advanced the R6 Cyber Security research program to secure digital infrastructures by developing a dynamic means to adaptively defend complex cyber systems. We hope that this work will benefit both our client’s efforts in system behavior modeling and cyber security to the overall benefit of the nation.« less

Viscous-Inviscid Methods in Unsteady Aerodynamic Analysis of Bio-Inspired Morphing Wings

NASA Astrophysics Data System (ADS)

Dhruv, Akash V.

Flight has been one of the greatest realizations of human imagination, revolutionizing communication and transportation over the years. This has greatly influenced the growth of technology itself, enabling researchers to communicate and share their ideas more effectively, extending the human potential to create more sophisticated systems. While the end product of a sophisticated technology makes our lives easier, its development process presents an array of challenges in itself. In last decade, scientists and engineers have turned towards bio-inspiration to design more efficient and robust aerodynamic systems to enhance the ability of Unmanned Aerial Vehicles (UAVs) to be operated in cluttered environments, where tight maneuverability and controllability are necessary. Effective use of UAVs in domestic airspace will mark the beginning of a new age in communication and transportation. The design of such complex systems necessitates the need for faster and more effective tools to perform preliminary investigations in design, thereby streamlining the design process. This thesis explores the implementation of numerical panel methods for aerodynamic analysis of bio-inspired morphing wings. Numerical panel methods have been one of the earliest forms of computational methods for aerodynamic analysis to be developed. Although the early editions of this method performed only inviscid analysis, the algorithm has matured over the years as a result of contributions made by prominent aerodynamicists. The method discussed in this thesis is influenced by recent advancements in panel methods and incorporates both viscous and inviscid analysis of multi-flap wings. The surface calculation of aerodynamic coefficients makes this method less computationally expensive than traditional Computational Fluid Dynamics (CFD) solvers available, and thus is effective when both speed and accuracy are desired. The morphing wing design, which consists of sequential feather-like flaps installed

Three-Dimensional-Printing of Bio-Inspired Composites.

PubMed

Xiang Gu, Grace; Su, Isabelle; Sharma, Shruti; Voros, Jamie L; Qin, Zhao; Buehler, Markus J

2016-02-01

Optimized for millions of years, natural materials often outperform synthetic materials due to their hierarchical structures and multifunctional abilities. They usually feature a complex architecture that consists of simple building blocks. Indeed, many natural materials such as bone, nacre, hair, and spider silk, have outstanding material properties, making them applicable to engineering applications that may require both mechanical resilience and environmental compatibility. However, such natural materials are very difficult to harvest in bulk, and may be toxic in the way they occur naturally, and therefore, it is critical to use alternative methods to fabricate materials that have material functions similar to material function as their natural counterparts for large-scale applications. Recent progress in additive manufacturing, especially the ability to print multiple materials at upper micrometer resolution, has given researchers an excellent instrument to design and reconstruct natural-inspired materials. The most advanced 3D-printer can now be used to manufacture samples to emulate their geometry and material composition with high fidelity. Its capabilities, in combination with computational modeling, have provided us even more opportunities for designing, optimizing, and testing the function of composite materials, in order to achieve composites of high mechanical resilience and reliability. In this review article, we focus on the advanced material properties of several multifunctional biological materials and discuss how the advanced 3D-printing techniques can be used to mimic their architectures and functions. Lastly, we discuss the limitations of 3D-printing, suggest possible future developments, and discuss applications using bio-inspired materials as a tool in bioengineering and other fields.

Three-Dimensional-Printing of Bio-Inspired Composites

PubMed Central

Xiang Gu, Grace; Su, Isabelle; Sharma, Shruti; Voros, Jamie L.; Qin, Zhao; Buehler, Markus J.

2016-01-01

Optimized for millions of years, natural materials often outperform synthetic materials due to their hierarchical structures and multifunctional abilities. They usually feature a complex architecture that consists of simple building blocks. Indeed, many natural materials such as bone, nacre, hair, and spider silk, have outstanding material properties, making them applicable to engineering applications that may require both mechanical resilience and environmental compatibility. However, such natural materials are very difficult to harvest in bulk, and may be toxic in the way they occur naturally, and therefore, it is critical to use alternative methods to fabricate materials that have material functions similar to material function as their natural counterparts for large-scale applications. Recent progress in additive manufacturing, especially the ability to print multiple materials at upper micrometer resolution, has given researchers an excellent instrument to design and reconstruct natural-inspired materials. The most advanced 3D-printer can now be used to manufacture samples to emulate their geometry and material composition with high fidelity. Its capabilities, in combination with computational modeling, have provided us even more opportunities for designing, optimizing, and testing the function of composite materials, in order to achieve composites of high mechanical resilience and reliability. In this review article, we focus on the advanced material properties of several multifunctional biological materials and discuss how the advanced 3D-printing techniques can be used to mimic their architectures and functions. Lastly, we discuss the limitations of 3D-printing, suggest possible future developments, and discuss applications using bio-inspired materials as a tool in bioengineering and other fields. PMID:26747791

Locomotion Dynamics for Bio-inspired Robots with Soft Appendages: Application to Flapping Flight and Passive Swimming

NASA Astrophysics Data System (ADS)

Boyer, Frédéric; Porez, Mathieu; Morsli, Ferhat; Morel, Yannick

2017-08-01

In animal locomotion, either in fish or flying insects, the use of flexible terminal organs or appendages greatly improves the performance of locomotion (thrust and lift). In this article, we propose a general unified framework for modeling and simulating the (bio-inspired) locomotion of robots using soft organs. The proposed approach is based on the model of Mobile Multibody Systems (MMS). The distributed flexibilities are modeled according to two major approaches: the Floating Frame Approach (FFA) and the Geometrically Exact Approach (GEA). Encompassing these two approaches in the Newton-Euler modeling formalism of robotics, this article proposes a unique modeling framework suited to the fast numerical integration of the dynamics of a MMS in both the FFA and the GEA. This general framework is applied on two illustrative examples drawn from bio-inspired locomotion: the passive swimming in von Karman Vortex Street, and the hovering flight with flexible flapping wings.

A bio-inspired design of live cell biosensors

NASA Astrophysics Data System (ADS)

Marcek Chorvatova, A.; Teplicky, T.; Pavlinska, Z.; Kronekova, Z.; Trelova, D.; Razga, F.; Nemethova, V.; Uhelska, L.; Lacik, I.; Chorvat, D.

2018-02-01

The last decade has witnessed a rapid growth of nanoscale-oriented biosensors that becomes one of the most promising and rapidly growing areas of modern research. Despite significant advancements in conception of such biosensors, most are based at evaluation of molecular, or protein interactions. It is however becoming increasingly evident that functionality of a living system does not reside in genome or in individual proteins, as no real biological functionality is expressed at these levels. Instead, to comprehend the true functioning of a biological system, it is essential to understand the integrative physiological behavior of the complex molecular interactions in their natural environment and precise spatio-temporal topology. In this contribution we therefore present a new concept for creation of biosensors, bio-inspired from true functioning of living cells, while monitoring their endogenous fluorescence, or autofluorescence.

A green and bio-inspired process to afford durable anti-biofilm properties to stainless steel.

PubMed

Faure, E; Vreuls, C; Falentin-Daudré, C; Zocchi, G; Van de Weerdt, C; Martial, J; Jérôme, C; Duwez, A-S; Detrembleur, C

2012-01-01

A bio-inspired durable anti-biofilm coating was developed for industrial stainless steel (SS) surfaces. Two polymers inspired from the adhesive and cross-linking properties of mussels were designed and assembled from aqueous solutions onto SS surfaces to afford durable coatings. Trypsin, a commercially available broad spectrum serine protease, was grafted as the final active layer of the coating. Its proteolytic activity after long immersion periods was demonstrated against several substrata, viz. a synthetic molecule, N-α-benzoyl-DL-arginine-p-nitroanilide hydrochloride (BAPNA), a protein, FTC-casein, and Gram-positive biofilm forming bacterium Staphylococcus epidermidis.

Miniaturized unified imaging system using bio-inspired fluidic lens

NASA Astrophysics Data System (ADS)

Tsai, Frank S.; Cho, Sung Hwan; Qiao, Wen; Kim, Nam-Hyong; Lo, Yu-Hwa

2008-08-01

Miniaturized imaging systems have become ubiquitous as they are found in an ever-increasing number of devices, such as cellular phones, personal digital assistants, and web cameras. Until now, the design and fabrication methodology of such systems have not been significantly different from conventional cameras. The only established method to achieve focusing is by varying the lens distance. On the other hand, the variable-shape crystalline lens found in animal eyes offers inspiration for a more natural way of achieving an optical system with high functionality. Learning from the working concepts of the optics in the animal kingdom, we developed bio-inspired fluidic lenses for a miniature universal imager with auto-focusing, macro, and super-macro capabilities. Because of the enormous dynamic range of fluidic lenses, the miniature camera can even function as a microscope. To compensate for the image quality difference between the central vision and peripheral vision and the shape difference between a solid-state image sensor and a curved retina, we adopted a hybrid design consisting of fluidic lenses for tunability and fixed lenses for aberration and color dispersion correction. A design of the world's smallest surgical camera with 3X optical zoom capabilities is also demonstrated using the approach of hybrid lenses.

Molecular simulations of self-assembling bio-inspired supramolecular systems and their connection to experiments

PubMed Central

Patmanidis, Ilias

2018-01-01

In bionanotechnology, the field of creating functional materials consisting of bio-inspired molecules, the function and shape of a nanostructure only appear through the assembly of many small molecules together. The large number of building blocks required to define a nanostructure combined with the many degrees of freedom in packing small molecules has long precluded molecular simulations, but recent advances in computational hardware as well as software have made classical simulations available to this strongly expanding field. Here, we review the state of the art in simulations of self-assembling bio-inspired supramolecular systems. We will first discuss progress in force fields, simulation protocols and enhanced sampling techniques using recent examples. Secondly, we will focus on efforts to enable the comparison of experimentally accessible observables and computational results. Experimental quantities that can be measured by microscopy, spectroscopy and scattering can be linked to simulation output either directly or indirectly, via quantum mechanical or semi-empirical techniques. Overall, we aim to provide an overview of the various computational approaches to understand not only the molecular architecture of nanostructures, but also the mechanism of their formation. PMID:29688238

Bio-Inspired Asynchronous Pixel Event Tricolor Vision Sensor.

PubMed

Lenero-Bardallo, Juan Antonio; Bryn, D H; Hafliger, Philipp

2014-06-01

This article investigates the potential of the first ever prototype of a vision sensor that combines tricolor stacked photo diodes with the bio-inspired asynchronous pixel event communication protocol known as Address Event Representation (AER). The stacked photo diodes are implemented in a 22 × 22 pixel array in a standard STM 90 nm CMOS process. Dynamic range is larger than 60 dB and pixels fill factor is 28%. The pixels employ either simple pulse frequency modulation (PFM) or a Time-to-First-Spike (TFS) mode. A heuristic linear combination of the chip's inherent pseudo colors serves to approximate RGB color representation. Furthermore, the sensor outputs can be processed to represent the radiation in the near infrared (NIR) band without employing external filters, and to color-encode direction of motion due to an asymmetry in the update rates of the different diode layers.

Disposable pen-shaped capillary gel electrophoresis cartridge for fluorescence detection of bio-molecules

NASA Astrophysics Data System (ADS)

Amirkhanian, Varoujan; Tsai, Shou-Kuan

2014-03-01

We introduce a novel and cost-effective capillary gel electrophoresis (CGE) system utilizing disposable pen-shaped gelcartridges for highly efficient, high speed, high throughput fluorescence detection of bio-molecules. The CGE system has been integrated with dual excitation and emission optical-fibers with micro-ball end design for fluorescence detection of bio-molecules separated and detected in a disposable pen-shaped capillary gel electrophoresis cartridge. The high-performance capillary gel electrophoresis (CGE) analyzer has been optimized for glycoprotein analysis type applications. Using commercially available labeling agent such as ANTS (8-aminonapthalene-1,3,6- trisulfonate) as an indicator, the capillary gel electrophoresis-based glycan analyzer provides high detection sensitivity and high resolving power in 2-5 minutes of separations. The system can hold total of 96 samples, which can be automatically analyzed within 4-5 hours. This affordable fiber optic based fluorescence detection system provides fast run times (4 minutes vs. 20 minutes with other CE systems), provides improved peak resolution, good linear dynamic range and reproducible migration times, that can be used in laboratories for high speed glycan (N-glycan) profiling applications. The CGE-based glycan analyzer will significantly increase the pace at which glycoprotein research is performed in the labs, saving hours of preparation time and assuring accurate, consistent and economical results.

Bio-Inspired Stretchable Absolute Pressure Sensor Network

PubMed Central

Guo, Yue; Li, Yu-Hung; Guo, Zhiqiang; Kim, Kyunglok; Chang, Fu-Kuo; Wang, Shan X.

2016-01-01

A bio-inspired absolute pressure sensor network has been developed. Absolute pressure sensors, distributed on multiple silicon islands, are connected as a network by stretchable polyimide wires. This sensor network, made on a 4’’ wafer, has 77 nodes and can be mounted on various curved surfaces to cover an area up to 0.64 m × 0.64 m, which is 100 times larger than its original size. Due to Micro Electro-Mechanical system (MEMS) surface micromachining technology, ultrathin sensing nodes can be realized with thicknesses of less than 100 µm. Additionally, good linearity and high sensitivity (~14 mV/V/bar) have been achieved. Since the MEMS sensor process has also been well integrated with a flexible polymer substrate process, the entire sensor network can be fabricated in a time-efficient and cost-effective manner. Moreover, an accurate pressure contour can be obtained from the sensor network. Therefore, this absolute pressure sensor network holds significant promise for smart vehicle applications, especially for unmanned aerial vehicles. PMID:26729134

From ice-binding proteins to bio-inspired antifreeze materials.

PubMed

Voets, I K

2017-07-19

Ice-binding proteins (IBP) facilitate survival under extreme conditions in diverse life forms. IBPs in polar fishes block further growth of internalized environmental ice and inhibit ice recrystallization of accumulated internal crystals. Algae use IBPs to structure ice, while ice adhesion is critical for the Antarctic bacterium Marinomonas primoryensis. Successful translation of this natural cryoprotective ability into man-made materials holds great promise but is still in its infancy. This review covers recent advances in the field of ice-binding proteins and their synthetic analogues, highlighting fundamental insights into IBP functioning as a foundation for the knowledge-based development of cheap, bio-inspired mimics through scalable production routes. Recent advances in the utilisation of IBPs and their analogues to e.g. improve cryopreservation, ice-templating strategies, gas hydrate inhibition and other technologies are presented.

Bio-inspired motion detection in an FPGA-based smart camera module.

PubMed

Köhler, T; Röchter, F; Lindemann, J P; Möller, R

2009-03-01

Flying insects, despite their relatively coarse vision and tiny nervous system, are capable of carrying out elegant and fast aerial manoeuvres. Studies of the fly visual system have shown that this is accomplished by the integration of signals from a large number of elementary motion detectors (EMDs) in just a few global flow detector cells. We developed an FPGA-based smart camera module with more than 10,000 single EMDs, which is closely modelled after insect motion-detection circuits with respect to overall architecture, resolution and inter-receptor spacing. Input to the EMD array is provided by a CMOS camera with a high frame rate. Designed as an adaptable solution for different engineering applications and as a testbed for biological models, the EMD detector type and parameters such as the EMD time constants, the motion-detection directions and the angle between correlated receptors are reconfigurable online. This allows a flexible and simultaneous detection of complex motion fields such as translation, rotation and looming, such that various tasks, e.g., obstacle avoidance, height/distance control or speed regulation can be performed by the same compact device.

Bio-inspired direct patterning functional nanothin microlines: controllable liquid transfer.

PubMed

Wang, Qianbin; Meng, Qingan; Wang, Pengwei; Liu, Huan; Jiang, Lei

2015-04-28

Developing a general and low-cost strategy that enables direct patterning of microlines with nanometer thickness from versatile liquid-phase functional materials and precise positioning of them on various substrates remains a challenge. Herein, with inspiration from the oriental wisdom to control ink transfer by Chinese brushes, we developed a facile and general writing strategy to directly pattern various functional microlines with homogeneous distribution and nanometer-scale thickness. It is demonstrated that the width and thickness of the microlines could be well-controlled by tuning the writing method, providing guidance for the adaptation of this technique to various systems. It is also shown that various functional liquid-phase materials, such as quantum dots, small molecules, polymers, and suspensions of nanoparticles, could directly write on the substrates with intrinsic physicochemical properties well-preserved. Moreover, this technique enabled direct patterning of liquid-phase materials on certain microdomains, even in multiple layered style, thus a microdomain localized chemical reaction and the patterned surface chemical modification were enabled. This bio-inspired direct writing device will shed light on the template-free printing of various functional micropatterns, as well as the integrated functional microdevices.

Catalytic applications of bio-inspired nanomaterials

NASA Astrophysics Data System (ADS)

Pacardo, Dennis Kien Balaong

The biomimetic synthesis of Pd nanoparticles was presented using the Pd4 peptide, TSNAVHPTLRHL, isolated from combinatorial phage display library. Using this approach, nearly monodisperse and spherical Pd nanoparticles were generated with an average diameter of 1.9 +/- 0.4 nm. The peptide-based nanocatalyst were employed in the Stille coupling reaction under energy-efficient and environmentally friendly reaction conditions of aqueous solvent, room temperature and very low catalyst loading. To this end, the Pd nanocatalyst generated high turnover frequency (TOF) value and quantitative yields using ≥ 0.005 mol% Pd as well as catalytic activities with different aryl halides containing electron-withdrawing and electron-donating groups. The Pd4-capped Pd nanoparticles followed the atom-leaching mechanism and were found to be selective with respect to substrate identity. On the other hand, the naturally-occurring R5 peptide (SSKKSGSYSGSKGSKRRIL) was employed in the synthesis of biotemplated Pd nanomaterials which showed morphological changes as a function of Pd:peptide ratio. TOF analysis for hydrogenation of olefinic alcohols showed similar catalytic activity regardless of nanomorphology. Determination of catalytic properties of these bio-inspired nanomaterials are important as they serve as model system for alternative green catalyst with applications in industrially important transformations.

Bio-inspired routes for synthesizing efficient nanoscale platinum electrocatalysts

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cha, Jennifer N.; Wang, Joseph

2014-08-31

The overall objective of the proposed research is to use fundamental advances in bionanotechnology to design powerful platinum nanocrystal electrocatalysts for fuel cell applications. The new economically-viable, environmentally-friendly, bottom-up biochemical synthetic strategy will produce platinum nanocrystals with tailored size, shape and crystal orientation, hence leading to a maximum electrochemical reactivity. There are five specific aims to the proposed bio-inspired strategy for synthesizing efficient electrocatalytic platinum nanocrystals: (1) isolate peptides that both selectively bind particular crystal faces of platinum and promote the nucleation and growth of particular nanocrystal morphologies, (2) pattern nanoscale 2-dimensional arrays of platinum nucleating peptides from DNA scaffolds,more » (3) investigate the combined use of substrate patterned peptides and soluble peptides on nanocrystal morphology and growth (4) synthesize platinum crystals on planar and large-area carbon electrode supports, and (5) perform detailed characterization of the electrocatalytic behavior as a function of catalyst size, shape and morphology. Project Description and Impact: This bio-inspired collaborative research effort will address key challenges in designing powerful electrocatalysts for fuel cell applications by employing nucleic acid scaffolds in combination with peptides to perform specific, environmentally-friendly, simultaneous bottom-up biochemical synthesis and patterned assembly of highly uniform and efficient platinum nanocrystal catalysts. Bulk synthesis of nanoparticles usually produces a range of sizes, accessible catalytic sites, crystal morphologies, and orientations, all of which lead to inconsistent catalytic activities. In contrast, biological systems routinely demonstrate exquisite control over inorganic syntheses at neutral pH and ambient temperature and pressures. Because the orientation and arrangement of the templating biomolecules can be

Novel bio-inspired smart control for hazard mitigation of civil structures

NASA Astrophysics Data System (ADS)

Kim, Yeesock; Kim, Changwon; Langari, Reza

2010-11-01

In this paper, a new bio-inspired controller is proposed for vibration mitigation of smart structures subjected to ground disturbances (i.e. earthquakes). The control system is developed through the integration of a brain emotional learning (BEL) algorithm with a proportional-integral-derivative (PID) controller and a semiactive inversion (Inv) algorithm. The BEL algorithm is based on the neurologically inspired computational model of the amygdala and the orbitofrontal cortex. To demonstrate the effectiveness of the proposed hybrid BEL-PID-Inv control algorithm, a seismically excited building structure equipped with a magnetorheological (MR) damper is investigated. The performance of the proposed hybrid BEL-PID-Inv control algorithm is compared with that of passive, PID, linear quadratic Gaussian (LQG), and BEL control systems. In the simulation, the robustness of the hybrid BEL-PID-Inv control algorithm in the presence of modeling uncertainties as well as external disturbances is investigated. It is shown that the proposed hybrid BEL-PID-Inv control algorithm is effective in improving the dynamic responses of seismically excited building structure-MR damper systems.

A bio-inspired glucose controller based on pancreatic β-cell physiology.

PubMed

Herrero, Pau; Georgiou, Pantelis; Oliver, Nick; Johnston, Desmond G; Toumazou, Christofer

2012-05-01

Control algorithms for closed-loop insulin delivery in type 1 diabetes have been mainly based on control engineering or artificial intelligence techniques. These, however, are not based on the physiology of the pancreas but seek to implement engineering solutions to biology. Developments in mathematical models of the β-cell physiology of the pancreas have described the glucose-induced insulin release from pancreatic β cells at a molecular level. This has facilitated development of a new class of bio-inspired glucose control algorithms that replicate the functionality of the biological pancreas. However, technologies for sensing glucose levels and delivering insulin use the subcutaneous route, which is nonphysiological and introduces some challenges. In this article, a novel glucose controller is presented as part of a bio-inspired artificial pancreas. A mathematical model of β-cell physiology was used as the core of the proposed controller. In order to deal with delays and lack of accuracy introduced by the subcutaneous route, insulin feedback and a gain scheduling strategy were employed. A United States Food and Drug Administration-accepted type 1 diabetes mellitus virtual population was used to validate the presented controller. Premeal and postmeal mean ± standard deviation blood glucose levels for the adult and adolescent populations were well within the target range set for the controller [(70, 180) mg/dl], with a percent time in range of 92.8 ± 7.3% for the adults and 83.5 ± 14% for the adolescents. This article shows for the first time very good glucose control in a virtual population with type 1 diabetes mellitus using a controller based on a subcellular β-cell model. © 2012 Diabetes Technology Society.

A Bio-Inspired Glucose Controller Based on Pancreatic β-Cell Physiology

PubMed Central

Herrero, Pau; Georgiou, Pantelis; Oliver, Nick; Johnston, Desmond G; Toumazou, Christofer

2012-01-01

Introduction Control algorithms for closed-loop insulin delivery in type 1 diabetes have been mainly based on control engineering or artificial intelligence techniques. These, however, are not based on the physiology of the pancreas but seek to implement engineering solutions to biology. Developments in mathematical models of the β-cell physiology of the pancreas have described the glucose-induced insulin release from pancreatic β cells at a molecular level. This has facilitated development of a new class of bio-inspired glucose control algorithms that replicate the functionality of the biological pancreas. However, technologies for sensing glucose levels and delivering insulin use the subcutaneous route, which is nonphysiological and introduces some challenges. In this article, a novel glucose controller is presented as part of a bio-inspired artificial pancreas. Methods A mathematical model of β-cell physiology was used as the core of the proposed controller. In order to deal with delays and lack of accuracy introduced by the subcutaneous route, insulin feedback and a gain scheduling strategy were employed. A United States Food and Drug Administration-accepted type 1 diabetes mellitus virtual population was used to validate the presented controller. Results Premeal and postmeal mean ± standard deviation blood glucose levels for the adult and adolescent populations were well within the target range set for the controller [(70, 180) mg/dl], with a percent time in range of 92.8 ± 7.3% for the adults and 83.5 ± 14% for the adolescents. Conclusions This article shows for the first time very good glucose control in a virtual population with type 1 diabetes mellitus using a controller based on a subcellular β-cell model. PMID:22768892

Nature as an engineer: one simple concept of a bio-inspired functional artificial muscle.

PubMed

Schmitt, S; Haeufle, D F B; Blickhan, R; Günther, M

2012-09-01

The biological muscle is a powerful, flexible and versatile actuator. Its intrinsic characteristics determine the way how movements are generated and controlled. Robotic and prosthetic applications expect to profit from relying on bio-inspired actuators which exhibit natural (muscle-like) characteristics. As of today, when constructing a technical actuator, it is not possible to copy the exact molecular structure of a biological muscle. Alternatively, the question may be put how its characteristics can be realized with known mechanical components. Recently, a mechanical construct for an artificial muscle was proposed, which exhibits hyperbolic force-velocity characteristics. In this paper, we promote the constructing concept which is made by substantiating the mechanical design of biological muscle by a simple model, proving the feasibility of its real-world implementation, and checking their output both for mutual consistency and agreement with biological measurements. In particular, the relations of force, enthalpy rate and mechanical efficiency versus contraction velocity of both the construct's technical implementation and its numerical model were determined in quick-release experiments. All model predictions for these relations and the hardware results are now in good agreement with the biological literature. We conclude that the construct represents a mechanical concept of natural actuation, which is suitable for laying down some useful suggestions when designing bio-inspired actuators.

From ice-binding proteins to bio-inspired antifreeze materials

PubMed Central

Voets, I. K.

2017-01-01

Ice-binding proteins (IBP) facilitate survival under extreme conditions in diverse life forms. IBPs in polar fishes block further growth of internalized environmental ice and inhibit ice recrystallization of accumulated internal crystals. Algae use IBPs to structure ice, while ice adhesion is critical for the Antarctic bacterium Marinomonas primoryensis. Successful translation of this natural cryoprotective ability into man-made materials holds great promise but is still in its infancy. This review covers recent advances in the field of ice-binding proteins and their synthetic analogues, highlighting fundamental insights into IBP functioning as a foundation for the knowledge-based development of cheap, bio-inspired mimics through scalable production routes. Recent advances in the utilisation of IBPs and their analogues to e.g. improve cryopreservation, ice-templating strategies, gas hydrate inhibition and other technologies are presented. PMID:28657626

Simplified bionic solutions: a simple bio-inspired vehicle collision detection system

PubMed Central

Hartbauer, Manfred

2018-01-01

Modern cars are equipped with both active and passive sensor systems that can detect potential collisions. In contrast, locusts avoid collisions solely by responding to certain visual cues that are associated with object looming. In neurophysiological experiments, I investigated the possibility that the ‘collision-detector neurons’ of locusts respond to impending collisions in films recorded with dashboard cameras of fast driving cars. In a complementary modelling approach, I developed a simple algorithm to reproduce the neuronal response that was recorded during object approach. Instead of applying elaborate algorithms that factored in object recognition and optic flow discrimination, I tested the hypothesis that motion detection restricted to a ‘danger zone’, in which frontal collisions on the motorways are most likely, is sufficient to estimate the risk of a collision. Furthermore, I investigated whether local motion vectors, obtained from the differential excitation of simulated direction-selective networks, could be used to predict evasive steering maneuvers and prevent undesired responses to motion artifacts. The results of the study demonstrate that the risk of impending collisions in real traffic scenes is mirrored in the excitation of the collision-detecting neuron (DCMD) of locusts. The modelling approach was able to reproduce this neuronal response even when the vehicle was driving at high speeds and image resolution was low (about 200 × 100 pixels). Furthermore, evasive maneuvers that involved changing the steering direction and steering force could be planned by comparing the differences in the overall excitation levels of the simulated right and left direction-selective networks. Additionally, it was possible to suppress undesired responses of the algorithm to translatory movements, camera shake and ground shadows by evaluating local motion vectors. These estimated collision risk values and evasive steering vectors could be used as input for

Simplified bionic solutions: a simple bio-inspired vehicle collision detection system.

PubMed

Hartbauer, Manfred

2017-02-15

Modern cars are equipped with both active and passive sensor systems that can detect potential collisions. In contrast, locusts avoid collisions solely by responding to certain visual cues that are associated with object looming. In neurophysiological experiments, I investigated the possibility that the 'collision-detector neurons' of locusts respond to impending collisions in films recorded with dashboard cameras of fast driving cars. In a complementary modelling approach, I developed a simple algorithm to reproduce the neuronal response that was recorded during object approach. Instead of applying elaborate algorithms that factored in object recognition and optic flow discrimination, I tested the hypothesis that motion detection restricted to a 'danger zone', in which frontal collisions on the motorways are most likely, is sufficient to estimate the risk of a collision. Furthermore, I investigated whether local motion vectors, obtained from the differential excitation of simulated direction-selective networks, could be used to predict evasive steering maneuvers and prevent undesired responses to motion artifacts. The results of the study demonstrate that the risk of impending collisions in real traffic scenes is mirrored in the excitation of the collision-detecting neuron (DCMD) of locusts. The modelling approach was able to reproduce this neuronal response even when the vehicle was driving at high speeds and image resolution was low (about 200  ×  100 pixels). Furthermore, evasive maneuvers that involved changing the steering direction and steering force could be planned by comparing the differences in the overall excitation levels of the simulated right and left direction-selective networks. Additionally, it was possible to suppress undesired responses of the algorithm to translatory movements, camera shake and ground shadows by evaluating local motion vectors. These estimated collision risk values and evasive steering vectors could be used as input

Visually guided gait modifications for stepping over an obstacle: a bio-inspired approach.

PubMed

Silva, Pedro; Matos, Vitor; Santos, Cristina P

2014-02-01

There is an increasing interest in conceiving robotic systems that are able to move and act in an unstructured and not predefined environment, for which autonomy and adaptability are crucial features. In nature, animals are autonomous biological systems, which often serve as bio-inspiration models, not only for their physical and mechanical properties, but also their control structures that enable adaptability and autonomy-for which learning is (at least) partially responsible. This work proposes a system which seeks to enable a quadruped robot to online learn to detect and to avoid stumbling on an obstacle in its path. The detection relies in a forward internal model that estimates the robot's perceptive information by exploring the locomotion repetitive nature. The system adapts the locomotion in order to place the robot optimally before attempting to step over the obstacle, avoiding any stumbling. Locomotion adaptation is achieved by changing control parameters of a central pattern generator (CPG)-based locomotion controller. The mechanism learns the necessary alterations to the stride length in order to adapt the locomotion by changing the required CPG parameter. Both learning tasks occur online and together define a sensorimotor map, which enables the robot to learn to step over the obstacle in its path. Simulation results show the feasibility of the proposed approach.

Training mechanical engineering students to utilize biological inspiration during product development.

PubMed

Bruck, Hugh A; Gershon, Alan L; Golden, Ira; Gupta, Satyandra K; Gyger, Lawrence S; Magrab, Edward B; Spranklin, Brent W

2007-12-01

The use of bio-inspiration for the development of new products and devices requires new educational tools for students consisting of appropriate design and manufacturing technologies, as well as curriculum. At the University of Maryland, new educational tools have been developed that introduce bio-inspired product realization to undergraduate mechanical engineering students. These tools include the development of a bio-inspired design repository, a concurrent fabrication and assembly manufacturing technology, a series of undergraduate curriculum modules and a new senior elective in the bio-inspired robotics area. This paper first presents an overview of the two new design and manufacturing technologies that enable students to realize bio-inspired products, and describes how these technologies are integrated into the undergraduate educational experience. Then, the undergraduate curriculum modules are presented, which provide students with the fundamental design and manufacturing principles needed to support bio-inspired product and device development. Finally, an elective bio-inspired robotics project course is present, which provides undergraduates with the opportunity to demonstrate the application of the knowledge acquired through the curriculum modules in their senior year using the new design and manufacturing technologies.

Bio-inspired Design Approached Antifouling Strategies

NASA Astrophysics Data System (ADS)

Fitzsimons, L.; Chapman, J.; Lawlor, A.; Regan, F.

2012-04-01

Biofouling exists as the undesirable accumulation of flora and fauna on a given substrate when immersed into an aquatic media. Its presence causes a range of deleterious effects for anyone faced in tackling the problem, which is more than often financially testing. Generally, the initial biofouling stage is stochastic and the attachment of microorganisms held fast in biofilm matrices is irreversible. Stability of the biofilm occurs when exopolymeric substances (EPS) are produced forming a protective surrounding, allowing the cohered microorganisms to colonise and thrive upon the surface. Therefore, if this initial stage of biofilm development can be prevented then it could be possible to prevent subsequent macro events that ensue. Environmental monitoring is one area that faces this challenge and forms the impetus of the work presented herein. In order to improve a monitoring device's lifetime, surface coatings with biocidal agents are applied to counteract these steps. This work shows the development of a range of novel materials, which demonstrate the ability to counteract and inhibit the initial stages of biofouling for monitoring devices. Natural bio-inspired surfaces have been developed using nano-functionalised coatings. All materials are tested in the field and positive results in reducing the biofouling challenge are demonstrated. The results from the deployment of antifouling materials, together with real-time, long-term water quality data from the test site are also shown.

Formation Control for Water-Jet USV Based on Bio-Inspired Method

NASA Astrophysics Data System (ADS)

Fu, Ming-yu; Wang, Duan-song; Wang, Cheng-long

2018-03-01

The formation control problem for underactuated unmanned surface vehicles (USVs) is addressed by a distributed strategy based on virtual leader strategy. The control system takes account of disturbance induced by external environment. With the coordinate transformation, the advantage of the proposed scheme is that the control point can be any point of the ship instead of the center of gravity. By introducing bio-inspired model, the formation control problem is addressed with backstepping method. This avoids complicated computation, simplifies the control law, and smoothes the input signals. The system uniform ultimate boundness is proven by Lyapunov stability theory with Young inequality. Simulation results are presented to verify the effectiveness and robust of the proposed controller.

Bio-inspired nacre-like composite films based on graphene with superior mechanical, electrical, and biocompatible properties.

PubMed

Li, Yuan-Qing; Yu, Ting; Yang, Tian-Yi; Zheng, Lian-Xi; Liao, Kin

2012-07-03

Bio-inspired multifunctional composite films based on reduced poly(vinyl alcohol)/graphene oxide (R-PVA/GO) layers are prepared by a facile solution casting method followed by a reduction procedure. The resulting films with nacre-like, bricks-and-mortar microstructure have excellent mechanical properties, electrical conductivity, and biocompatibility. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Image sensor system with bio-inspired efficient coding and adaptation.

PubMed

Okuno, Hirotsugu; Yagi, Tetsuya

2012-08-01

We designed and implemented an image sensor system equipped with three bio-inspired coding and adaptation strategies: logarithmic transform, local average subtraction, and feedback gain control. The system comprises a field-programmable gate array (FPGA), a resistive network, and active pixel sensors (APS), whose light intensity-voltage characteristics are controllable. The system employs multiple time-varying reset voltage signals for APS in order to realize multiple logarithmic intensity-voltage characteristics, which are controlled so that the entropy of the output image is maximized. The system also employs local average subtraction and gain control in order to obtain images with an appropriate contrast. The local average is calculated by the resistive network instantaneously. The designed system was successfully used to obtain appropriate images of objects that were subjected to large changes in illumination.

In-plane crashworthiness of bio-inspired hierarchical honeycombs

DOE PAGES

Yin, Hanfeng; Huang, Xiaofei; Scarpa, Fabrizio; ...

2018-03-13

Biological tissues like bone, wood, and sponge possess hierarchical cellular topologies, which are lightweight and feature an excellent energy absorption capability. Here we present a system of bio-inspired hierarchical honeycomb structures based on hexagonal, Kagome, and triangular tessellations. The hierarchical designs and a reference regular honeycomb configuration are subjected to simulated in-plane impact using the nonlinear finite element code LS-DYNA. The numerical simulation results show that the triangular hierarchical honeycomb provides the best performance compared to the other two hierarchical honeycombs, and features more than twice the energy absorbed by the regular honeycomb under similar loading conditions. We also proposemore » a parametric study correlating the microstructure parameters (hierarchical length ratio r and the number of sub cells N) to the energy absorption capacity of these hierarchical honeycombs. The triangular hierarchical honeycomb with N = 2 and r = 1/8 shows the highest energy absorption capacity among all the investigated cases, and this configuration could be employed as a benchmark for the design of future safety protective systems.« less

In-plane crashworthiness of bio-inspired hierarchical honeycombs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yin, Hanfeng; Huang, Xiaofei; Scarpa, Fabrizio

Biological tissues like bone, wood, and sponge possess hierarchical cellular topologies, which are lightweight and feature an excellent energy absorption capability. Here we present a system of bio-inspired hierarchical honeycomb structures based on hexagonal, Kagome, and triangular tessellations. The hierarchical designs and a reference regular honeycomb configuration are subjected to simulated in-plane impact using the nonlinear finite element code LS-DYNA. The numerical simulation results show that the triangular hierarchical honeycomb provides the best performance compared to the other two hierarchical honeycombs, and features more than twice the energy absorbed by the regular honeycomb under similar loading conditions. We also proposemore » a parametric study correlating the microstructure parameters (hierarchical length ratio r and the number of sub cells N) to the energy absorption capacity of these hierarchical honeycombs. The triangular hierarchical honeycomb with N = 2 and r = 1/8 shows the highest energy absorption capacity among all the investigated cases, and this configuration could be employed as a benchmark for the design of future safety protective systems.« less

A survey on bio inspired meta heuristic based clustering protocols for wireless sensor networks

NASA Astrophysics Data System (ADS)

Datta, A.; Nandakumar, S.

2017-11-01

Recent studies have shown that utilizing a mobile sink to harvest and carry data from a Wireless Sensor Network (WSN) can improve network operational efficiency as well as maintain uniform energy consumption by the sensor nodes in the network. Due to Sink mobility, the path between two sensor nodes continuously changes and this has a profound effect on the operational longevity of the network and a need arises for a protocol which utilizes minimal resources in maintaining routes between the mobile sink and the sensor nodes. Swarm Intelligence based techniques inspired by the foraging behavior of ants, termites and honey bees can be artificially simulated and utilized to solve real wireless network problems. The author presents a brief survey on various bio inspired swarm intelligence based protocols used in routing data in wireless sensor networks while outlining their general principle and operation.

Bio-inspired optimization algorithms for optical parameter extraction of dielectric materials: A comparative study

NASA Astrophysics Data System (ADS)

Ghulam Saber, Md; Arif Shahriar, Kh; Ahmed, Ashik; Hasan Sagor, Rakibul

2016-10-01

Particle swarm optimization (PSO) and invasive weed optimization (IWO) algorithms are used for extracting the modeling parameters of materials useful for optics and photonics research community. These two bio-inspired algorithms are used here for the first time in this particular field to the best of our knowledge. The algorithms are used for modeling graphene oxide and the performances of the two are compared. Two objective functions are used for different boundary values. Root mean square (RMS) deviation is determined and compared.

Performance Analysis of the Enhanced Bio-Inspired Planning Algorithm for Rapid Situation Awareness Response

DTIC Science & Technology

2013-10-18

low cost robot testbed. 15. SUBJECT TERMS Bio-inspired trajectory generation, in-situ obstacle avoidance, low-cost LEGO robots, vision- based...will not affect the solution optimality and thus will be regarded as zero. Following the LP motion strategy Eq. (1), the position vector of the Lego ...Lobatto (LGL) method [14], the position of Lego robot can be further represented as ’ 1 ,( )j p jD   ζ ζ (6) in which ,0 ,,..., T j j j

Operant conditioning: a minimal components requirement in artificial spiking neurons designed for bio-inspired robot's controller

PubMed Central

Cyr, André; Boukadoum, Mounir; Thériault, Frédéric

2014-01-01

In this paper, we investigate the operant conditioning (OC) learning process within a bio-inspired paradigm, using artificial spiking neural networks (ASNN) to act as robot brain controllers. In biological agents, OC results in behavioral changes learned from the consequences of previous actions, based on progressive prediction adjustment from rewarding or punishing signals. In a neurorobotics context, virtual and physical autonomous robots may benefit from a similar learning skill when facing unknown and unsupervised environments. In this work, we demonstrate that a simple invariant micro-circuit can sustain OC in multiple learning scenarios. The motivation for this new OC implementation model stems from the relatively complex alternatives that have been described in the computational literature and recent advances in neurobiology. Our elementary kernel includes only a few crucial neurons, synaptic links and originally from the integration of habituation and spike-timing dependent plasticity as learning rules. Using several tasks of incremental complexity, our results show that a minimal neural component set is sufficient to realize many OC procedures. Hence, with the proposed OC module, designing learning tasks with an ASNN and a bio-inspired robot context leads to simpler neural architectures for achieving complex behaviors. PMID:25120464

Operant conditioning: a minimal components requirement in artificial spiking neurons designed for bio-inspired robot's controller.

PubMed

Cyr, André; Boukadoum, Mounir; Thériault, Frédéric

2014-01-01

In this paper, we investigate the operant conditioning (OC) learning process within a bio-inspired paradigm, using artificial spiking neural networks (ASNN) to act as robot brain controllers. In biological agents, OC results in behavioral changes learned from the consequences of previous actions, based on progressive prediction adjustment from rewarding or punishing signals. In a neurorobotics context, virtual and physical autonomous robots may benefit from a similar learning skill when facing unknown and unsupervised environments. In this work, we demonstrate that a simple invariant micro-circuit can sustain OC in multiple learning scenarios. The motivation for this new OC implementation model stems from the relatively complex alternatives that have been described in the computational literature and recent advances in neurobiology. Our elementary kernel includes only a few crucial neurons, synaptic links and originally from the integration of habituation and spike-timing dependent plasticity as learning rules. Using several tasks of incremental complexity, our results show that a minimal neural component set is sufficient to realize many OC procedures. Hence, with the proposed OC module, designing learning tasks with an ASNN and a bio-inspired robot context leads to simpler neural architectures for achieving complex behaviors.

A Bio-Inspired, Motion-Based Analysis of Crowd Behavior Attributes Relevance to Motion Transparency, Velocity Gradients, and Motion Patterns

PubMed Central

Raudies, Florian; Neumann, Heiko

2012-01-01

The analysis of motion crowds is concerned with the detection of potential hazards for individuals of the crowd. Existing methods analyze the statistics of pixel motion to classify non-dangerous or dangerous behavior, to detect outlier motions, or to estimate the mean throughput of people for an image region. We suggest a biologically inspired model for the analysis of motion crowds that extracts motion features indicative for potential dangers in crowd behavior. Our model consists of stages for motion detection, integration, and pattern detection that model functions of the primate primary visual cortex area (V1), the middle temporal area (MT), and the medial superior temporal area (MST), respectively. This model allows for the processing of motion transparency, the appearance of multiple motions in the same visual region, in addition to processing opaque motion. We suggest that motion transparency helps to identify “danger zones” in motion crowds. For instance, motion transparency occurs in small exit passages during evacuation. However, motion transparency occurs also for non-dangerous crowd behavior when people move in opposite directions organized into separate lanes. Our analysis suggests: The combination of motion transparency and a slow motion speed can be used for labeling of candidate regions that contain dangerous behavior. In addition, locally detected decelerations or negative speed gradients of motions are a precursor of danger in crowd behavior as are globally detected motion patterns that show a contraction toward a single point. In sum, motion transparency, image speeds, motion patterns, and speed gradients extracted from visual motion in videos are important features to describe the behavioral state of a motion crowd. PMID:23300930

Bio-inspired Murray materials for mass transfer and activity

PubMed Central

Zheng, Xianfeng; Shen, Guofang; Wang, Chao; Li, Yu; Dunphy, Darren; Hasan, Tawfique; Brinker, C. Jeffrey; Su, Bao-Lian

2017-01-01

Both plants and animals possess analogous tissues containing hierarchical networks of pores, with pore size ratios that have evolved to maximize mass transport and rates of reactions. The underlying physical principles of this optimized hierarchical design are embodied in Murray's law. However, we are yet to realize the benefit of mimicking nature's Murray networks in synthetic materials due to the challenges in fabricating vascularized structures. Here we emulate optimum natural systems following Murray's law using a bottom-up approach. Such bio-inspired materials, whose pore sizes decrease across multiple scales and finally terminate in size-invariant units like plant stems, leaf veins and vascular and respiratory systems provide hierarchical branching and precise diameter ratios for connecting multi-scale pores from macro to micro levels. Our Murray material mimics enable highly enhanced mass exchange and transfer in liquid–solid, gas–solid and electrochemical reactions and exhibit enhanced performance in photocatalysis, gas sensing and as Li-ion battery electrodes. PMID:28382972

Bio-inspired Murray materials for mass transfer and activity

NASA Astrophysics Data System (ADS)

Zheng, Xianfeng; Shen, Guofang; Wang, Chao; Li, Yu; Dunphy, Darren; Hasan, Tawfique; Brinker, C. Jeffrey; Su, Bao-Lian

2017-04-01

Both plants and animals possess analogous tissues containing hierarchical networks of pores, with pore size ratios that have evolved to maximize mass transport and rates of reactions. The underlying physical principles of this optimized hierarchical design are embodied in Murray's law. However, we are yet to realize the benefit of mimicking nature's Murray networks in synthetic materials due to the challenges in fabricating vascularized structures. Here we emulate optimum natural systems following Murray's law using a bottom-up approach. Such bio-inspired materials, whose pore sizes decrease across multiple scales and finally terminate in size-invariant units like plant stems, leaf veins and vascular and respiratory systems provide hierarchical branching and precise diameter ratios for connecting multi-scale pores from macro to micro levels. Our Murray material mimics enable highly enhanced mass exchange and transfer in liquid-solid, gas-solid and electrochemical reactions and exhibit enhanced performance in photocatalysis, gas sensing and as Li-ion battery electrodes.

PCR-free quantitative detection of genetically modified organism from raw materials. An electrochemiluminescence-based bio bar code method.

PubMed

Zhu, Debin; Tang, Yabing; Xing, Da; Chen, Wei R

2008-05-15

A bio bar code assay based on oligonucleotide-modified gold nanoparticles (Au-NPs) provides a PCR-free method for quantitative detection of nucleic acid targets. However, the current bio bar code assay requires lengthy experimental procedures including the preparation and release of bar code DNA probes from the target-nanoparticle complex and immobilization and hybridization of the probes for quantification. Herein, we report a novel PCR-free electrochemiluminescence (ECL)-based bio bar code assay for the quantitative detection of genetically modified organism (GMO) from raw materials. It consists of tris-(2,2'-bipyridyl) ruthenium (TBR)-labeled bar code DNA, nucleic acid hybridization using Au-NPs and biotin-labeled probes, and selective capture of the hybridization complex by streptavidin-coated paramagnetic beads. The detection of target DNA is realized by direct measurement of ECL emission of TBR. It can quantitatively detect target nucleic acids with high speed and sensitivity. This method can be used to quantitatively detect GMO fragments from real GMO products.

Design and development of bio-inspired framework for reservoir operation optimization

NASA Astrophysics Data System (ADS)

Asvini, M. Sakthi; Amudha, T.

2017-12-01

Frameworks for optimal reservoir operation play an important role in the management of water resources and delivery of economic benefits. Effective utilization and conservation of water from reservoirs helps to manage water deficit periods. The main challenge in reservoir optimization is to design operating rules that can be used to inform real-time decisions on reservoir release. We develop a bio-inspired framework for the optimization of reservoir release to satisfy the diverse needs of various stakeholders. In this work, single-objective optimization and multiobjective optimization problems are formulated using an algorithm known as "strawberry optimization" and tested with actual reservoir data. Results indicate that well planned reservoir operations lead to efficient deployment of the reservoir water with the help of optimal release patterns.

FE analysis of SMA-based bio-inspired bone-joint system

NASA Astrophysics Data System (ADS)

Yang, S.; Seelecke, S.

2009-10-01

This paper presents the finite element (FE) analysis of a bio-inspired bone-joint system. Motivated by the BATMAV project, which aims at the development of a micro-air-vehicle platform that implements bat-like flapping flight capabilities, we study the actuation of a typical elbow joint, using shape memory alloy (SMA) in a dual manner. Micro-scale martensitic SMA wires are used as 'metal muscles' to actuate a system of humerus, elbow joint and radius, in concert with austenitic wires, which operate as flexible joints due to their superelastic character. For the FE analysis, the humerus and radius are modeled as standard elastic beams, while the elbow joint and muscle wires use the Achenbach-Muller-Seelecke SMA model as beams and cable elements, respectively. The particular focus of the paper is on the implementation of the above SMA model in COMSOL.

A bio-inspired system for spatio-temporal recognition in static and video imagery

NASA Astrophysics Data System (ADS)

Khosla, Deepak; Moore, Christopher K.; Chelian, Suhas

2007-04-01

This paper presents a bio-inspired method for spatio-temporal recognition in static and video imagery. It builds upon and extends our previous work on a bio-inspired Visual Attention and object Recognition System (VARS). The VARS approach locates and recognizes objects in a single frame. This work presents two extensions of VARS. The first extension is a Scene Recognition Engine (SCE) that learns to recognize spatial relationships between objects that compose a particular scene category in static imagery. This could be used for recognizing the category of a scene, e.g., office vs. kitchen scene. The second extension is the Event Recognition Engine (ERE) that recognizes spatio-temporal sequences or events in sequences. This extension uses a working memory model to recognize events and behaviors in video imagery by maintaining and recognizing ordered spatio-temporal sequences. The working memory model is based on an ARTSTORE1 neural network that combines an ART-based neural network with a cascade of sustained temporal order recurrent (STORE)1 neural networks. A series of Default ARTMAP classifiers ascribes event labels to these sequences. Our preliminary studies have shown that this extension is robust to variations in an object's motion profile. We evaluated the performance of the SCE and ERE on real datasets. The SCE module was tested on a visual scene classification task using the LabelMe2 dataset. The ERE was tested on real world video footage of vehicles and pedestrians in a street scene. Our system is able to recognize the events in this footage involving vehicles and pedestrians.

A bio-inspired swarm robot coordination algorithm for multiple target searching

NASA Astrophysics Data System (ADS)

Meng, Yan; Gan, Jing; Desai, Sachi

2008-04-01

The coordination of a multi-robot system searching for multi targets is challenging under dynamic environment since the multi-robot system demands group coherence (agents need to have the incentive to work together faithfully) and group competence (agents need to know how to work together well). In our previous proposed bio-inspired coordination method, Local Interaction through Virtual Stigmergy (LIVS), one problem is the considerable randomness of the robot movement during coordination, which may lead to more power consumption and longer searching time. To address these issues, an adaptive LIVS (ALIVS) method is proposed in this paper, which not only considers the travel cost and target weight, but also predicting the target/robot ratio and potential robot redundancy with respect to the detected targets. Furthermore, a dynamic weight adjustment is also applied to improve the searching performance. This new method a truly distributed method where each robot makes its own decision based on its local sensing information and the information from its neighbors. Basically, each robot only communicates with its neighbors through a virtual stigmergy mechanism and makes its local movement decision based on a Particle Swarm Optimization (PSO) algorithm. The proposed ALIVS algorithm has been implemented on the embodied robot simulator, Player/Stage, in a searching target. The simulation results demonstrate the efficiency and robustness in a power-efficient manner with the real-world constraints.

Towards a Coupled Vortex Particle and Acoustic Boundary Element Solver to Predict the Noise Production of Bio-Inspired Propulsion

NASA Astrophysics Data System (ADS)

Wagenhoffer, Nathan; Moored, Keith; Jaworski, Justin

2016-11-01

The design of quiet and efficient bio-inspired propulsive concepts requires a rapid, unified computational framework that integrates the coupled fluid dynamics with the noise generation. Such a framework is developed where the fluid motion is modeled with a two-dimensional unsteady boundary element method that includes a vortex-particle wake. The unsteady surface forces from the potential flow solver are then passed to an acoustic boundary element solver to predict the radiated sound in low-Mach-number flows. The use of the boundary element method for both the hydrodynamic and acoustic solvers permits dramatic computational acceleration by application of the fast multiple method. The reduced order of calculations due to the fast multipole method allows for greater spatial resolution of the vortical wake per unit of computational time. The coupled flow-acoustic solver is validated against canonical vortex-sound problems. The capability of the coupled solver is demonstrated by analyzing the performance and noise production of an isolated bio-inspired swimmer and of tandem swimmers.

Biologically-Inspired Deceptive Behavior for a Robot

DTIC Science & Technology

2012-01-01

by sending false signals either intentionally or unintentionally, are essential for animals’ survival. For example, camouflage and mimicry are well...detection by both predators and their prey. While camouflage or mimicry are examples of unknowingly deceiving, a deceptive behavior can include...face this situation, where it is important to discourage an adversary from discovering a protected site, so the application of these bio -inspired

PCR-free quantitative detection of genetically modified organism from raw materials – A novel electrochemiluminescence-based bio-barcode method

PubMed Central

Zhu, Debin; Tang, Yabing; Xing, Da; Chen, Wei R.

2018-01-01

Bio-barcode assay based on oligonucleotide-modified gold nanoparticles (Au-NPs) provides a PCR-free method for quantitative detection of nucleic acid targets. However, the current bio-barcode assay requires lengthy experimental procedures including the preparation and release of barcode DNA probes from the target-nanoparticle complex, and immobilization and hybridization of the probes for quantification. Herein, we report a novel PCR-free electrochemiluminescence (ECL)-based bio-barcode assay for the quantitative detection of genetically modified organism (GMO) from raw materials. It consists of tris-(2’2’-bipyridyl) ruthenium (TBR)-labele barcode DNA, nucleic acid hybridization using Au-NPs and biotin-labeled probes, and selective capture of the hybridization complex by streptavidin-coated paramagnetic beads. The detection of target DNA is realized by direct measurement of ECL emission of TBR. It can quantitatively detect target nucleic acids with high speed and sensitivity. This method can be used to quantitatively detect GMO fragments from real GMO products. PMID:18386909

A novel angle computation and calibration algorithm of bio-inspired sky-light polarization navigation sensor.

PubMed

Xian, Zhiwen; Hu, Xiaoping; Lian, Junxiang; Zhang, Lilian; Cao, Juliang; Wang, Yujie; Ma, Tao

2014-09-15

Navigation plays a vital role in our daily life. As traditional and commonly used navigation technologies, Inertial Navigation System (INS) and Global Navigation Satellite System (GNSS) can provide accurate location information, but suffer from the accumulative error of inertial sensors and cannot be used in a satellite denied environment. The remarkable navigation ability of animals shows that the pattern of the polarization sky can be used for navigation. A bio-inspired POLarization Navigation Sensor (POLNS) is constructed to detect the polarization of skylight. Contrary to the previous approach, we utilize all the outputs of POLNS to compute input polarization angle, based on Least Squares, which provides optimal angle estimation. In addition, a new sensor calibration algorithm is presented, in which the installation angle errors and sensor biases are taken into consideration. Derivation and implementation of our calibration algorithm are discussed in detail. To evaluate the performance of our algorithms, simulation and real data test are done to compare our algorithms with several exiting algorithms. Comparison results indicate that our algorithms are superior to the others and are more feasible and effective in practice.

Engineered bio-inspired coating for reduction of flow separation

NASA Astrophysics Data System (ADS)

Bocanegra Evans, Humberto; Hamed, Ali M.; Gorumlu, Serdar; Doosttalab, Ali; Aksak, Burak; Chamorro, Leonardo P.; Castillo, Luciano

2017-11-01

Flow control using passive strategies has received notable attention in the last decades as a way to increase mixing and reduce skin drag, among others. Here, we present a bio-inspired coating, composed by uniformly distributed pillars with diverging tips, that is able to reduce the recirculation region in highly separated flows. This is demonstrated with laboratory experiments in a refractive index-matching flume at Reynolds number Reθ 1200 . The flow over an expanding channel following a S835 wing section was characterized with the coating and with smooth walls. High-resolution, wall-normal particle image velocimetry show a significant reduction of the reversed flow with the coating, where the region with reverse flow was reduced by 60 % . The performance of the micro-scale coating is surprising since the size of the fibers are nearly coincident with the viscous length scale (k+ 1). Additionally, the flow control properties of the surface do not depend on hydrophobicity, giving the coating the capability to work in both air and water media.

A Bio-Inspired Two-Layer Sensing Structure of Polypeptide and Multiple-Walled Carbon Nanotube to Sense Small Molecular Gases

PubMed Central

Wang, Li-Chun; Su, Tseng-Hsiung; Ho, Cheng-Long; Yang, Shang-Ren; Chiu, Shih-Wen; Kuo, Han-Wen; Tang, Kea-Tiong

2015-01-01

In this paper, we propose a bio-inspired, two-layer, multiple-walled carbon nanotube (MWCNT)-polypeptide composite sensing device. The MWCNT serves as a responsive and conductive layer, and the nonselective polypeptide (40 mer) coating the top of the MWCNT acts as a filter into which small molecular gases pass. Instead of using selective peptides to sense specific odorants, we propose using nonselective, peptide-based sensors to monitor various types of volatile organic compounds. In this study, depending on gas interaction and molecular sizes, the randomly selected polypeptide enabled the recognition of certain polar volatile chemical vapors, such as amines, and the improved discernment of low-concentration gases. The results of our investigation demonstrated that the polypeptide-coated sensors can detect ammonia at a level of several hundred ppm and barely responded to triethylamine. PMID:25751078

Multimodal Bio-Inspired Tactile Sensing Module for Surface Characterization †

PubMed Central

Alves de Oliveira, Thiago Eustaquio; Cretu, Ana-Maria; Petriu, Emil M.

2017-01-01

Robots are expected to recognize the properties of objects in order to handle them safely and efficiently in a variety of applications, such as health and elder care, manufacturing, or high-risk environments. This paper explores the issue of surface characterization by monitoring the signals acquired by a novel bio-inspired tactile probe in contact with ridged surfaces. The tactile module comprises a nine Degree of Freedom Microelectromechanical Magnetic, Angular Rate, and Gravity system (9-DOF MEMS MARG) and a deep MEMS pressure sensor embedded in a compliant structure that mimics the function and the organization of mechanoreceptors in human skin as well as the hardness of the human skin. When the modules tip slides over a surface, the MARG unit vibrates and the deep pressure sensor captures the overall normal force exerted. The module is evaluated in two experiments. The first experiment compares the frequency content of the data collected in two setups: one when the module is mounted over a linear motion carriage that slides four grating patterns at constant velocities; the second when the module is carried by a robotic finger in contact with the same grating patterns while performing a sliding motion, similar to the exploratory motion employed by humans to detect object roughness. As expected, in the linear setup, the magnitude spectrum of the sensors’ output shows that the module can detect the applied stimuli with frequencies ranging from 3.66 Hz to 11.54 Hz with an overall maximum error of ±0.1 Hz. The second experiment shows how localized features extracted from the data collected by the robotic finger setup over seven synthetic shapes can be used to classify them. The classification method consists on applying multiscale principal components analysis prior to the classification with a multilayer neural network. Achieved accuracies from 85.1% to 98.9% for the various sensor types demonstrate the usefulness of traditional MEMS as tactile sensors embedded

Bio-Photonic Detection of Various Cellular Cultures

NASA Astrophysics Data System (ADS)

Hann, Patrick; Garzon, Maria; Pfeiffer, Erik; Lofland, Samuel; Knoesel, Ernst

2008-03-01

Since it is non-invasive, there has been increased research in the field of bio-optics. Many biological systems display an unusual phenomenon, delayed luminescence, produced by what is known as bio-photons. We present an apparatus and procedure for the detection of these ultra-weak photonic emissions using a single photon detection device. The results of bread yeast, saccramyces, and algae will be presented and compared to other reports in the literature

Bio-inspired engineering of cell- and virus-like nanoparticles for drug delivery.

PubMed

Parodi, Alessandro; Molinaro, Roberto; Sushnitha, Manuela; Evangelopoulos, Michael; Martinez, Jonathan O; Arrighetti, Noemi; Corbo, Claudia; Tasciotti, Ennio

2017-12-01

The engineering of future generations of nanodelivery systems aims at the creation of multifunctional vectors endowed with improved circulation, enhanced targeting and responsiveness to the biological environment. Moving past purely bio-inert systems, researchers have begun to create nanoparticles capable of proactively interacting with the biology of the body. Nature offers a wide-range of sources of inspiration for the synthesis of more effective drug delivery platforms. Because the nano-bio-interface is the key driver of nanoparticle behavior and function, the modification of nanoparticles' surfaces allows the transfer of biological properties to synthetic carriers by imparting them with a biological identity. Modulation of these surface characteristics governs nanoparticle interactions with the biological barriers they encounter. Building off these observations, we provide here an overview of virus- and cell-derived biomimetic delivery systems that combine the intrinsic hallmarks of biological membranes with the delivery capabilities of synthetic carriers. We describe the features and properties of biomimetic delivery systems, recapitulating the distinctive traits and functions of viruses, exosomes, platelets, red and white blood cells. By mimicking these biological entities, we will learn how to more efficiently interact with the human body and refine our ability to negotiate with the biological barriers that impair the therapeutic efficacy of nanoparticles. Copyright © 2017. Published by Elsevier Ltd.

Bio-inspired display of polarization information using selected visual cues

NASA Astrophysics Data System (ADS)

Yemelyanov, Konstantin M.; Lin, Shih-Schon; Luis, William Q.; Pugh, Edward N., Jr.; Engheta, Nader

2003-12-01

For imaging systems the polarization of electromagnetic waves carries much potentially useful information about such features of the world as the surface shape, material contents, local curvature of objects, as well as about the relative locations of the source, object and imaging system. The imaging system of the human eye however, is "polarization-blind", and cannot utilize the polarization of light without the aid of an artificial, polarization-sensitive instrument. Therefore, polarization information captured by a man-made polarimetric imaging system must be displayed to a human observer in the form of visual cues that are naturally processed by the human visual system, while essentially preserving the other important non-polarization information (such as spectral and intensity information) in an image. In other words, some forms of sensory substitution are needed for representing polarization "signals" without affecting other visual information such as color and brightness. We are investigating several bio-inspired representational methodologies for mapping polarization information into visual cues readily perceived by the human visual system, and determining which mappings are most suitable for specific applications such as object detection, navigation, sensing, scene classifications, and surface deformation. The visual cues and strategies we are exploring are the use of coherently moving dots superimposed on image to represent various range of polarization signals, overlaying textures with spatial and/or temporal signatures to segregate regions of image with differing polarization, modulating luminance and/or color contrast of scenes in terms of certain aspects of polarization values, and fusing polarization images into intensity-only images. In this talk, we will present samples of our findings in this area.

A bio-inspired memory model for structural health monitoring

NASA Astrophysics Data System (ADS)

Zheng, Wei; Zhu, Yong

2009-04-01

Long-term structural health monitoring (SHM) systems need intelligent management of the monitoring data. By analogy with the way the human brain processes memories, we present a bio-inspired memory model (BIMM) that does not require prior knowledge of the structure parameters. The model contains three time-domain areas: a sensory memory area, a short-term memory area and a long-term memory area. First, the initial parameters of the structural state are specified to establish safety criteria. Then the large amount of monitoring data that falls within the safety limits is filtered while the data outside the safety limits are captured instantly in the sensory memory area. Second, disturbance signals are distinguished from danger signals in the short-term memory area. Finally, the stable data of the structural balance state are preserved in the long-term memory area. A strategy for priority scheduling via fuzzy c-means for the proposed model is then introduced. An experiment on bridge tower deformation demonstrates that the proposed model can be applied for real-time acquisition, limited-space storage and intelligent mining of the monitoring data in a long-term SHM system.

A Bio-Inspired, Heavy-Metal-Free, Dual-Electrolyte Liquid Battery towards Sustainable Energy Storage.

PubMed

Ding, Yu; Yu, Guihua

2016-04-04

Wide-scale exploitation of renewable energy requires low-cost efficient energy storage devices. The use of metal-free, inexpensive redox-active organic materials represents a promising direction for environmental-friendly, cost-effective sustainable energy storage. To this end, a liquid battery is designed using hydroquinone (H2BQ) aqueous solution as catholyte and graphite in aprotic electrolyte as anode. The working potential can reach 3.4 V, with specific capacity of 395 mA h g(-1) and stable capacity retention about 99.7% per cycle. Such high potential and capacity is achieved using only C, H and O atoms as building blocks for redox species, and the replacement of Li metal with graphite anode can circumvent potential safety issues. As H2BQ can be extracted from biomass directly and its redox reaction mimics the bio-electrochemical process of quinones in nature, using such a bio-inspired organic compound in batteries enables access to greener and more sustainable energy-storage technology. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Bio-inspired surfactant assisted nano-catalyst impregnation of Solid-Oxide Fuel Cell (SOFC) electrodes

DOE PAGES

Ozmen, Ozcan; Zondlo, John W.; Lee, Shiwoo; ...

2015-11-02

A bio-inspired surfactant was utilized to assist in the efficient impregnation of a nano-CeO₂ catalyst throughout both porous Solid Oxide Fuel Cells (SOFC’s) electrodes simultaneously. The process included the initial modification of electrode pore walls with a polydopamine film. The cell was then submersed into a cerium salt solution. The amount of nano-CeO₂ deposited per impregnation step increased by 3.5 times by utilizing this two-step protocol in comparison to a conventional drip impregnation method. The impregnated cells exhibited a 20% higher power density than a baseline cell without the nano-catalyst at 750°C (using humid H₂ fuel).

A three dimensional unsteady iterative panel method with vortex particle wakes and boundary layer model for bio-inspired multi-body wings

NASA Astrophysics Data System (ADS)

Dhruv, Akash; Blower, Christopher; Wickenheiser, Adam M.

2015-03-01

The ability of UAVs to operate in complex and hostile environments makes them useful in military and civil operations concerning surveillance and reconnaissance. However, limitations in size of UAVs and communication delays prohibit their operation close to the ground and in cluttered environments, which increase risks associated with turbulence and wind gusts that cause trajectory deviations and potential loss of the vehicle. In the last decade, scientists and engineers have turned towards bio-inspiration to solve these issues by developing innovative flow control methods that offer better stability, controllability, and maneuverability. This paper presents an aerodynamic load solver for bio-inspired wings that consist of an array of feather-like flaps installed across the upper and lower surfaces in both the chord- and span-wise directions, mimicking the feathers of an avian wing. Each flap has the ability to rotate into both the wing body and the inbound airflow, generating complex flap configurations unobtainable by traditional wings that offer improved aerodynamic stability against gusting flows and turbulence. The solver discussed is an unsteady three-dimensional iterative doublet panel method with vortex particle wakes. This panel method models the wake-body interactions between multiple flaps effectively without the need to define specific wake geometries, thereby eliminating the need to manually model the wake for each configuration. To incorporate viscous flow characteristics, an iterative boundary layer theory is employed, modeling laminar, transitional and turbulent regions over the wing's surfaces, in addition to flow separation and reattachment locations. This technique enables the boundary layer to influence the wake strength and geometry both within the wing and aft of the trailing edge. The results obtained from this solver are validated using experimental data from a low-speed suction wind tunnel operating at Reynolds Number 300,000. This method

A Novel Angle Computation and Calibration Algorithm of Bio-Inspired Sky-Light Polarization Navigation Sensor

PubMed Central

Xian, Zhiwen; Hu, Xiaoping; Lian, Junxiang; Zhang, Lilian; Cao, Juliang; Wang, Yujie; Ma, Tao

2014-01-01

Navigation plays a vital role in our daily life. As traditional and commonly used navigation technologies, Inertial Navigation System (INS) and Global Navigation Satellite System (GNSS) can provide accurate location information, but suffer from the accumulative error of inertial sensors and cannot be used in a satellite denied environment. The remarkable navigation ability of animals shows that the pattern of the polarization sky can be used for navigation. A bio-inspired POLarization Navigation Sensor (POLNS) is constructed to detect the polarization of skylight. Contrary to the previous approach, we utilize all the outputs of POLNS to compute input polarization angle, based on Least Squares, which provides optimal angle estimation. In addition, a new sensor calibration algorithm is presented, in which the installation angle errors and sensor biases are taken into consideration. Derivation and implementation of our calibration algorithm are discussed in detail. To evaluate the performance of our algorithms, simulation and real data test are done to compare our algorithms with several exiting algorithms. Comparison results indicate that our algorithms are superior to the others and are more feasible and effective in practice. PMID:25225872

Bio-inspired adaptive feedback error learning architecture for motor control.

PubMed

Tolu, Silvia; Vanegas, Mauricio; Luque, Niceto R; Garrido, Jesús A; Ros, Eduardo

2012-10-01

This study proposes an adaptive control architecture based on an accurate regression method called Locally Weighted Projection Regression (LWPR) and on a bio-inspired module, such as a cerebellar-like engine. This hybrid architecture takes full advantage of the machine learning module (LWPR kernel) to abstract an optimized representation of the sensorimotor space while the cerebellar component integrates this to generate corrective terms in the framework of a control task. Furthermore, we illustrate how the use of a simple adaptive error feedback term allows to use the proposed architecture even in the absence of an accurate analytic reference model. The presented approach achieves an accurate control with low gain corrective terms (for compliant control schemes). We evaluate the contribution of the different components of the proposed scheme comparing the obtained performance with alternative approaches. Then, we show that the presented architecture can be used for accurate manipulation of different objects when their physical properties are not directly known by the controller. We evaluate how the scheme scales for simulated plants of high Degrees of Freedom (7-DOFs).

A Bio-Inspired Herbal Tea Flavour Assessment Technique

PubMed Central

Zakaria, Nur Zawatil Isqi; Masnan, Maz Jamilah; Zakaria, Ammar; Shakaff, Ali Yeon Md

2014-01-01

Herbal-based products are becoming a widespread production trend among manufacturers for the domestic and international markets. As the production increases to meet the market demand, it is very crucial for the manufacturer to ensure that their products have met specific criteria and fulfil the intended quality determined by the quality controller. One famous herbal-based product is herbal tea. This paper investigates bio-inspired flavour assessments in a data fusion framework involving an e-nose and e-tongue. The objectives are to attain good classification of different types and brands of herbal tea, classification of different flavour masking effects and finally classification of different concentrations of herbal tea. Two data fusion levels were employed in this research, low level data fusion and intermediate level data fusion. Four classification approaches; LDA, SVM, KNN and PNN were examined in search of the best classifier to achieve the research objectives. In order to evaluate the classifiers' performance, an error estimator based on k-fold cross validation and leave-one-out were applied. Classification based on GC-MS TIC data was also included as a comparison to the classification performance using fusion approaches. Generally, KNN outperformed the other classification techniques for the three flavour assessments in the low level data fusion and intermediate level data fusion. However, the classification results based on GC-MS TIC data are varied. PMID:25010697

Bio-inspired nano-sensor-enhanced CNN visual computer.

PubMed

Porod, Wolfgang; Werblin, Frank; Chua, Leon O; Roska, Tamas; Rodriguez-Vazquez, Angel; Roska, Botond; Fay, Patrick; Bernstein, Gary H; Huang, Yih-Fang; Csurgay, Arpad I

2004-05-01

Nanotechnology opens new ways to utilize recent discoveries in biological image processing by translating the underlying functional concepts into the design of CNN (cellular neural/nonlinear network)-based systems incorporating nanoelectronic devices. There is a natural intersection joining studies of retinal processing, spatio-temporal nonlinear dynamics embodied in CNN, and the possibility of miniaturizing the technology through nanotechnology. This intersection serves as the springboard for our multidisciplinary project. Biological feature and motion detectors map directly into the spatio-temporal dynamics of CNN for target recognition, image stabilization, and tracking. The neural interactions underlying color processing will drive the development of nanoscale multispectral sensor arrays for image fusion. Implementing such nanoscale sensors on a CNN platform will allow the implementation of device feedback control, a hallmark of biological sensory systems. These biologically inspired CNN subroutines are incorporated into the new world of analog-and-logic algorithms and software, containing also many other active-wave computing mechanisms, including nature-inspired (physics and chemistry) as well as PDE-based sophisticated spatio-temporal algorithms. Our goal is to design and develop several miniature prototype devices for target detection, navigation, tracking, and robotics. This paper presents an example illustrating the synergies emerging from the convergence of nanotechnology, biotechnology, and information and cognitive science.

Bio-Inspired Polarized Skylight-Based Navigation Sensors: A Review

PubMed Central

Karman, Salmah B.; Diah, S. Zaleha M.; Gebeshuber, Ille C.

2012-01-01

Animal senses cover a broad range of signal types and signal bandwidths and have inspired various sensors and bioinstrumentation devices for biological and medical applications. Insects, such as desert ants and honeybees, for example, utilize polarized skylight pattern-based information in their navigation activities. They reliably return to their nests and hives from places many kilometers away. The insect navigation system involves the dorsal rim area in their compound eyes and the corresponding polarization sensitive neurons in the brain. The dorsal rim area is equipped with photoreceptors, which have orthogonally arranged small hair-like structures termed microvilli. These are the specialized sensors for the detection of polarized skylight patterns (e-vector orientation). Various research groups have been working on the development of novel navigation systems inspired by polarized skylight-based navigation in animals. Their major contributions are critically reviewed. One focus of current research activities is on imitating the integration path mechanism in desert ants. The potential for simple, high performance miniaturized bioinstrumentation that can assist people in navigation will be explored. PMID:23202158

Bio-inspired polarized skylight-based navigation sensors: a review.

PubMed

Karman, Salmah B; Diah, S Zaleha M; Gebeshuber, Ille C

2012-10-24

Animal senses cover a broad range of signal types and signal bandwidths and have inspired various sensors and bioinstrumentation devices for biological and medical applications. Insects, such as desert ants and honeybees, for example, utilize polarized skylight pattern-based information in their navigation activities. They reliably return to their nests and hives from places many kilometers away. The insect navigation system involves the dorsal rim area in their compound eyes and the corresponding polarization sensitive neurons in the brain. The dorsal rim area is equipped with photoreceptors, which have orthogonally arranged small hair-like structures termed microvilli. These are the specialized sensors for the detection of polarized skylight patterns (e-vector orientation). Various research groups have been working on the development of novel navigation systems inspired by polarized skylight-based navigation in animals. Their major contributions are critically reviewed. One focus of current research activities is on imitating the integration path mechanism in desert ants. The potential for simple, high performance miniaturized bioinstrumentation that can assist people in navigation will be explored.

The neuroscience of vision-based grasping: a functional review for computational modeling and bio-inspired robotics.

PubMed

Chinellato, Eris; Del Pobil, Angel P

2009-06-01

The topic of vision-based grasping is being widely studied in humans and in other primates using various techniques and with different goals. The fundamental related findings are reviewed in this paper, with the aim of providing researchers from different fields, including intelligent robotics and neural computation, a comprehensive but accessible view on the subject. A detailed description of the principal sensorimotor processes and the brain areas involved is provided following a functional perspective, in order to make this survey especially useful for computational modeling and bio-inspired robotic applications.

Bio-inspired in situ growth of monolayer silver nanoparticles on graphene oxide paper as multifunctional substrate

NASA Astrophysics Data System (ADS)

Li, Shi-Kuo; Yan, You-Xian; Wang, Jin-Long; Yu, Shu-Hong

2013-11-01

In this study, we report a facile bio-inspired method for large-scale preparation of highly dispersed Ag nanoparticles (NPs) on the surface of flexible reduced graphene oxide (rGO) paper with using dopamine (DA) both as a reductant and a surface modifier. Through the self-polymerization of dopamine, free-standing GO paper can be simultaneously reduced and modified with following in situ growth of monolayer Ag NPs on such a substrate. The spherical Ag NPs with an average diameter of 80 nm have a narrow size distribution and tunable cover density. Such a flexible rGO/Ag hybrid paper presents enhanced antibacterial activity against E. coli and a high active and sensitive SERS response toward Rhodamine 6G (R6G) molecules. The detection signals can be obtained while the R6G concentration is as low as to 10-8 M. This work provides a simple strategy for large-scale fabrication of monolayer Ag NPs on flexible rGO paper as a portable antibacterial substrate and a potential SERS substrate for molecular detection applications.In this study, we report a facile bio-inspired method for large-scale preparation of highly dispersed Ag nanoparticles (NPs) on the surface of flexible reduced graphene oxide (rGO) paper with using dopamine (DA) both as a reductant and a surface modifier. Through the self-polymerization of dopamine, free-standing GO paper can be simultaneously reduced and modified with following in situ growth of monolayer Ag NPs on such a substrate. The spherical Ag NPs with an average diameter of 80 nm have a narrow size distribution and tunable cover density. Such a flexible rGO/Ag hybrid paper presents enhanced antibacterial activity against E. coli and a high active and sensitive SERS response toward Rhodamine 6G (R6G) molecules. The detection signals can be obtained while the R6G concentration is as low as to 10-8 M. This work provides a simple strategy for large-scale fabrication of monolayer Ag NPs on flexible rGO paper as a portable antibacterial substrate and a

Design and development of a bio-inspired, under-actuated soft gripper.

PubMed

Hassan, Taimoor; Manti, Mariangela; Passetti, Giovanni; d'Elia, Nicolò; Cianchetti, Matteo; Laschi, Cecilia

2015-08-01

The development of robotic devices able to perform manipulation tasks mimicking the human hand has been assessed on large scale. This work stands in the challenging scenario where soft materials are combined with bio-inspired design in order to develop soft grippers with improved grasping and holding capabilities. We are going to show a low-cost, under-actuated and adaptable soft gripper, highlighting the design and the manufacturing process. In particular, a critical analysis is made among three versions of the gripper with same design and actuation mechanism, but based on different materials. A novel actuation principle has been implemented in both cases, in order to reduce the encumbrance of the entire system and improve its aesthetics. Grasping and holding capabilities have been tested for each device, with target objects varying in shape, size and material. Results highlight synergy between the geometry and the intrinsic properties of the soft material, showing the way to novel design principles for soft grippers.

Light manipulation for organic optoelectronics using bio-inspired moth's eye nanostructures.

PubMed

Zhou, Lei; Ou, Qing-Dong; Chen, Jing-De; Shen, Su; Tang, Jian-Xin; Li, Yan-Qing; Lee, Shuit-Tong

2014-02-10

Organic-based optoelectronic devices, including light-emitting diodes (OLEDs) and solar cells (OSCs) hold great promise as low-cost and large-area electro-optical devices and renewable energy sources. However, further improvement in efficiency remains a daunting challenge due to limited light extraction or absorption in conventional device architectures. Here we report a universal method of optical manipulation of light by integrating a dual-side bio-inspired moth's eye nanostructure with broadband anti-reflective and quasi-omnidirectional properties. Light out-coupling efficiency of OLEDs with stacked triple emission units is over 2 times that of a conventional device, resulting in drastic increase in external quantum efficiency and current efficiency to 119.7% and 366 cd A(-1) without introducing spectral distortion and directionality. Similarly, the light in-coupling efficiency of OSCs is increased 20%, yielding an enhanced power conversion efficiency of 9.33%. We anticipate this method would offer a convenient and scalable way for inexpensive and high-efficiency organic optoelectronic designs.

Directed assembly of bio-inspired hierarchical materials with controlled nanofibrillar architectures

NASA Astrophysics Data System (ADS)

Tseng, Peter; Napier, Bradley; Zhao, Siwei; Mitropoulos, Alexander N.; Applegate, Matthew B.; Marelli, Benedetto; Kaplan, David L.; Omenetto, Fiorenzo G.

2017-05-01

In natural systems, directed self-assembly of structural proteins produces complex, hierarchical materials that exhibit a unique combination of mechanical, chemical and transport properties. This controlled process covers dimensions ranging from the nano- to the macroscale. Such materials are desirable to synthesize integrated and adaptive materials and systems. We describe a bio-inspired process to generate hierarchically defined structures with multiscale morphology by using regenerated silk fibroin. The combination of protein self-assembly and microscale mechanical constraints is used to form oriented, porous nanofibrillar networks within predesigned macroscopic structures. This approach allows us to predefine the mechanical and physical properties of these materials, achieved by the definition of gradients in nano- to macroscale order. We fabricate centimetre-scale material geometries including anchors, cables, lattices and webs, as well as functional materials with structure-dependent strength and anisotropic thermal transport. Finally, multiple three-dimensional geometries and doped nanofibrillar constructs are presented to illustrate the facile integration of synthetic and natural additives to form functional, interactive, hierarchical networks.

Design and Characterization of a Novel Bio-inspired Hair Flow Sensor Based on Resonant Sensing

NASA Astrophysics Data System (ADS)

Guo, X.; Yang, B.; Wang, Q. H.; Lu, C. F.; Hu, D.

2018-03-01

Flow sensors inspired by the natural hair sensing mechanism have great prospect in the research of micro-autonomous system and technology (MAST) for the three-dimensional structure characteristics with high spatial and quality utilization. A novel bio-inspired hair flow sensor (BHFS) based on resonant sensing with a unique asymmetric design is presented in this paper. A hair transducer and a signal detector which is constituted of a two-stage micro-leverage mechanism and two symmetrical resonators (double ended tuning fork, DETF) are adopted to realize the high sensitivity to air flow. The sensitivity of the proposed BHFS is improved significantly than the published ones due to the high sensitivity of resonators and the higher amplification factor possessed by the two-stage micro-leverage mechanism. The standard deep dry silicon on glass (DDSOG) process is chosen to fabricate the proposed BHFS. The experiment result demonstrates that the fabricated BHFS has a mechanical sensitivity of 5.26 Hz/(m/s)2 at a resonant frequency of 22 kHz with the hair height of 6 mm.

An Advanced Bio-Inspired PhotoPlethysmoGraphy (PPG) and ECG Pattern Recognition System for Medical Assessment

PubMed Central

Rundo, Francesco; Ortis, Alessandro

2018-01-01

Physiological signals are widely used to perform medical assessment for monitoring an extensive range of pathologies, usually related to cardio-vascular diseases. Among these, both PhotoPlethysmoGraphy (PPG) and Electrocardiography (ECG) signals are those more employed. PPG signals are an emerging non-invasive measurement technique used to study blood volume pulsations through the detection and analysis of the back-scattered optical radiation coming from the skin. ECG is the process of recording the electrical activity of the heart over a period of time using electrodes placed on the skin. In the present paper we propose a physiological ECG/PPG “combo” pipeline using an innovative bio-inspired nonlinear system based on a reaction-diffusion mathematical model, implemented by means of the Cellular Neural Network (CNN) methodology, to filter PPG signal by assigning a recognition score to the waveforms in the time series. The resulting “clean” PPG signal exempts from distortion and artifacts is used to validate for diagnostic purpose an EGC signal simultaneously detected for a same patient. The multisite combo PPG-ECG system proposed in this work overpasses the limitations of the state of the art in this field providing a reliable system for assessing the above-mentioned physiological parameters and their monitoring over time for robust medical assessment. The proposed system has been validated and the results confirmed the robustness of the proposed approach. PMID:29385774

An Advanced Bio-Inspired PhotoPlethysmoGraphy (PPG) and ECG Pattern Recognition System for Medical Assessment.

PubMed

Rundo, Francesco; Conoci, Sabrina; Ortis, Alessandro; Battiato, Sebastiano

2018-01-30

Physiological signals are widely used to perform medical assessment for monitoring an extensive range of pathologies, usually related to cardio-vascular diseases. Among these, both PhotoPlethysmoGraphy (PPG) and Electrocardiography (ECG) signals are those more employed. PPG signals are an emerging non-invasive measurement technique used to study blood volume pulsations through the detection and analysis of the back-scattered optical radiation coming from the skin. ECG is the process of recording the electrical activity of the heart over a period of time using electrodes placed on the skin. In the present paper we propose a physiological ECG/PPG "combo" pipeline using an innovative bio-inspired nonlinear system based on a reaction-diffusion mathematical model, implemented by means of the Cellular Neural Network (CNN) methodology, to filter PPG signal by assigning a recognition score to the waveforms in the time series. The resulting "clean" PPG signal exempts from distortion and artifacts is used to validate for diagnostic purpose an EGC signal simultaneously detected for a same patient. The multisite combo PPG-ECG system proposed in this work overpasses the limitations of the state of the art in this field providing a reliable system for assessing the above-mentioned physiological parameters and their monitoring over time for robust medical assessment. The proposed system has been validated and the results confirmed the robustness of the proposed approach.

Bio-inspired benchmark generator for extracellular multi-unit recordings

PubMed Central

Mondragón-González, Sirenia Lizbeth; Burguière, Eric

2017-01-01

The analysis of multi-unit extracellular recordings of brain activity has led to the development of numerous tools, ranging from signal processing algorithms to electronic devices and applications. Currently, the evaluation and optimisation of these tools are hampered by the lack of ground-truth databases of neural signals. These databases must be parameterisable, easy to generate and bio-inspired, i.e. containing features encountered in real electrophysiological recording sessions. Towards that end, this article introduces an original computational approach to create fully annotated and parameterised benchmark datasets, generated from the summation of three components: neural signals from compartmental models and recorded extracellular spikes, non-stationary slow oscillations, and a variety of different types of artefacts. We present three application examples. (1) We reproduced in-vivo extracellular hippocampal multi-unit recordings from either tetrode or polytrode designs. (2) We simulated recordings in two different experimental conditions: anaesthetised and awake subjects. (3) Last, we also conducted a series of simulations to study the impact of different level of artefacts on extracellular recordings and their influence in the frequency domain. Beyond the results presented here, such a benchmark dataset generator has many applications such as calibration, evaluation and development of both hardware and software architectures. PMID:28233819

AER synthetic generation in hardware for bio-inspired spiking systems

NASA Astrophysics Data System (ADS)

Linares-Barranco, Alejandro; Linares-Barranco, Bernabe; Jimenez-Moreno, Gabriel; Civit-Balcells, Anton

2005-06-01

Address Event Representation (AER) is an emergent neuromorphic interchip communication protocol that allows for real-time virtual massive connectivity between huge number neurons located on different chips. By exploiting high speed digital communication circuits (with nano-seconds timings), synaptic neural connections can be time multiplexed, while neural activity signals (with mili-seconds timings) are sampled at low frequencies. Also, neurons generate 'events' according to their activity levels. More active neurons generate more events per unit time, and access the interchip communication channel more frequently, while neurons with low activity consume less communication bandwidth. When building multi-chip muti-layered AER systems it is absolutely necessary to have a computer interface that allows (a) to read AER interchip traffic into the computer and visualize it on screen, and (b) convert conventional frame-based video stream in the computer into AER and inject it at some point of the AER structure. This is necessary for test and debugging of complex AER systems. This paper addresses the problem of converting, in a computer, a conventional frame-based video stream into the spike event based representation AER. There exist several proposed software methods for synthetic generation of AER for bio-inspired systems. This paper presents a hardware implementation for one method, which is based on Linear-Feedback-Shift-Register (LFSR) pseudo-random number generation. The sequence of events generated by this hardware, which follows a Poisson distribution like a biological neuron, has been reconstructed using two AER integrator cells. The error of reconstruction for a set of images that produces different traffic loads of event in the AER bus is used as evaluation criteria. A VHDL description of the method, that includes the Xilinx PCI Core, has been implemented and tested using a general purpose PCI-AER board. This PCI-AER board has been developed by authors, and uses

Fusion of nacre, mussel, and lotus leaf: bio-inspired graphene composite paper with multifunctional integration

NASA Astrophysics Data System (ADS)

Zhong, Da; Yang, Qinglin; Guo, Lin; Dou, Shixue; Liu, Kesong; Jiang, Lei

2013-06-01

Multifunctional integration is an inherent characteristic for biological materials with multiscale structures. Learning from nature is an effective approach for scientists and engineers to construct multifunctional materials. In nature, mollusks (abalone), mussels, and the lotus have evolved different and optimized solutions to survive. Here, bio-inspired multifunctional graphene composite paper was fabricated in situ through the fusion of the different biological solutions from nacre (brick-and-mortar structure), mussel adhesive protein (adhesive property and reducing character), and the lotus leaf (self-cleaning effect). Owing to the special properties (self-polymerization, reduction, and adhesion), dopamine could be simultaneously used as a reducing agent for graphene oxide and as an adhesive, similar to the mortar in nacre, to crosslink the adjacent graphene. The resultant nacre-like graphene paper exhibited stable superhydrophobicity, self-cleaning, anti-corrosion, and remarkable mechanical properties underwater.Multifunctional integration is an inherent characteristic for biological materials with multiscale structures. Learning from nature is an effective approach for scientists and engineers to construct multifunctional materials. In nature, mollusks (abalone), mussels, and the lotus have evolved different and optimized solutions to survive. Here, bio-inspired multifunctional graphene composite paper was fabricated in situ through the fusion of the different biological solutions from nacre (brick-and-mortar structure), mussel adhesive protein (adhesive property and reducing character), and the lotus leaf (self-cleaning effect). Owing to the special properties (self-polymerization, reduction, and adhesion), dopamine could be simultaneously used as a reducing agent for graphene oxide and as an adhesive, similar to the mortar in nacre, to crosslink the adjacent graphene. The resultant nacre-like graphene paper exhibited stable superhydrophobicity, self

Dynamic analysis of a bio-inspired climbing robot using ADAMS-Simulink co-simulation

NASA Astrophysics Data System (ADS)

Chattopadhyay, P.; Dikshit, H.; Majumder, A.; Ghoshal, S.; Maity, A.

2018-04-01

Climbing robot has been an area of interest since the demand of inspection of pipeline, nuclear power plant, and various big structure is growing up rapidly. This paper represents the development of a bio-inspired modular robot which mimics inchworm locomotion during climbing. In the present paper, the climbing motion is achieved only on a flat vertical plane by magnetic adhesion principle. The robot is modelled as a 4-link planar mechanism with three revolute joints actuated by DC servo motors. Sinusoidal gait pattern is used to approximate the motion of an inchworm. The dynamics of the robot is presented by using ADAMS/MATLAB co-simulation methodology. The simulation result gives the maximum value of joint torque during one complete cycle of motion. This torque value is used for the selection of servo motor specifications required to build the prototype.

Obstacle traversal and self-righting of bio-inspired robots reveal the physics of multi-modal locomotion

NASA Astrophysics Data System (ADS)

Li, Chen; Fearing, Ronald; Full, Robert

Most animals move in nature in a variety of locomotor modes. For example, to traverse obstacles like dense vegetation, cockroaches can climb over, push across, reorient their bodies to maneuver through slits, or even transition among these modes forming diverse locomotor pathways; if flipped over, they can also self-right using wings or legs to generate body pitch or roll. By contrast, most locomotion studies have focused on a single mode such as running, walking, or jumping, and robots are still far from capable of life-like, robust, multi-modal locomotion in the real world. Here, we present two recent studies using bio-inspired robots, together with new locomotion energy landscapes derived from locomotor-environment interaction physics, to begin to understand the physics of multi-modal locomotion. (1) Our experiment of a cockroach-inspired legged robot traversing grass-like beam obstacles reveals that, with a terradynamically ``streamlined'' rounded body like that of the insect, robot traversal becomes more probable by accessing locomotor pathways that overcome lower potential energy barriers. (2) Our experiment of a cockroach-inspired self-righting robot further suggests that body vibrations are crucial for exploring locomotion energy landscapes and reaching lower barrier pathways. Finally, we posit that our new framework of locomotion energy landscapes holds promise to better understand and predict multi-modal biological and robotic movement.

Tunable band gaps in bio-inspired periodic composites with nacre-like microstructure

NASA Astrophysics Data System (ADS)

Chen, Yanyu; Wang, Lifeng

2014-08-01

Periodic composite materials have many promising applications due to their unique ability to control the propagation of waves. Here, we report the existence and frequency tunability of complete elastic wave band gaps in bio-inspired periodic composites with nacre-like, brick-and-mortar microstructure. Numerical results show that complete band gaps in these periodic composites derive from local resonances or Bragg scattering, depending on the lattice angle and the volume fraction of each phase in the composites. The investigation of elastic wave propagation in finite periodic composites validates the simulated complete band gaps and further reveals the mechanisms leading to complete band gaps. Moreover, our results indicate that the topological arrangement of the mineral platelets and changes of material properties can be utilized to tune the evolution of complete band gaps. Our finding provides new opportunities to design mechanically robust periodic composite materials for wave absorption under hostile environments, such as for deep water applications.

Bio-Inspired Distributed Decision Algorithms for Anomaly Detection

DTIC Science & Technology

2017-03-01

TERMS DIAMoND, Local Anomaly Detector, Total Impact Estimation, Threat Level Estimator 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT UU...21 4.2 Performance of the DIAMoND Algorithm as a DNS-Server Level Attack Detection and Mitigation...with 6 Nodes ........................................................................................ 13 8 Hierarchical 2- Level Topology

Carbon-Nanotube-Supported Bio-Inspired Nickel Catalyst and Its Integration in Hybrid Hydrogen/Air Fuel Cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gentil, Solène; Lalaoui, Noémie; Dutta, Arnab

A biomimetic nickel bis-diphosphine complex incorporating the amino-acid arginine in the outer coordination sphere, was immobilized on modified single-wall carbon nanotubes (SWCNTs) through electrostatic interactions. The sur-face-confined catalyst is characterized by a reversible 2-electron/2-proton redox process at potentials close to the equibrium potential of the H+/H2 couple. Consequently, the functionalized redox nanomaterial exhibits reversible electrocatalytic activity for the H2/2H+ interconversion over a broad range of pH. This system exhibits catalytic bias, analogous to hydrogenases, resulting in high turnover frequencies at low overpotentials for electrocatalytic H2 oxida-tion between pH 0 and 7. This allowed integrating such bio-inspired nanomaterial together with amore » multicopper oxi-dase at the cathode side in a hybrid bioinspired/enzymatic hydrogen fuel cell. This device delivers ~2 mW cm–2 with an open-circuit voltage of 1.0 V at room temperature and pH 5, which sets a new efficiency record for a bio-related hydrogen fuel cell with base metal catalysts.« less

Bio-inspired active materials

NASA Astrophysics Data System (ADS)

Fratzl, Peter

Biological tissues are naturally interactive and adaptive. In general, these features are due to the action of cells that provide sensing, actuation as well as tissue remodelling. There are also examples of materials synthesized by living organisms, such as plant seeds, which fulfil an active function without living cells working as mechanosensors and actuators. Thus the activity of these materials is based on physical principles alone, which provides inspiration for new concepts for artificial active materials. We will describe structural principles leading to movement in seed capsules triggered by ambient humidity and discuss the influence of internal architecture on the overall mechanical behaviour of materials, including actuation and motility. Several conceptual systems for actuating planar structures will be discussed.

Constrained VPH+: a local path planning algorithm for a bio-inspired crawling robot with customized ultrasonic scanning sensor.

PubMed

Rao, Akshay; Elara, Mohan Rajesh; Elangovan, Karthikeyan

This paper aims to develop a local path planning algorithm for a bio-inspired, reconfigurable crawling robot. A detailed description of the robotic platform is first provided, and the suitability for deployment of each of the current state-of-the-art local path planners is analyzed after an extensive literature review. The Enhanced Vector Polar Histogram algorithm is described and reformulated to better fit the requirements of the platform. The algorithm is deployed on the robotic platform in crawling configuration and favorably compared with other state-of-the-art local path planning algorithms.

Effects of bio-inspired microscale roughness on macroscale flow structures

NASA Astrophysics Data System (ADS)

Bocanegra Evans, Humberto; Hamed, Ali M.; Gorumlu, Serdar; Doosttalab, Ali; Aksak, Burak; Chamorro, Leonardo P.; Castillo, Luciano

2016-11-01

The interaction between rough surfaces and flows is a complex physical situation that produces rich flow phenomena. While random roughness typically increases drag, properly engineered roughness patterns may produce positive results, e.g. dimples in a golf ball. Here we present a set of PIV measurements in an index matched facility of the effect of a bio-inspired surface that consists of an array of mushroom-shaped micro-pillars. The experiments are carried out-under fully wetted conditions-in a flow with adverse pressure gradient, triggering flow separation. The introduction of the micro-pillars dramatically decreases the size of the recirculation bubble; the area with backflow is reduced by approximately 60%. This suggests a positive impact on the form drag generated by the fluid. Furthermore, a negligible effect is seen on the turbulence production terms. The micro-pillars affect the flow by generating low and high pressure perturbations at the interface between the bulk and roughness layer, in a fashion comparable to that of synthetic jets. The passive approach, however, facilitates the implementation of this coating. As the mechanism does not rely on surface hydrophobicity, it is well suited for underwater applications and its functionality should not degrade over time.

Bio-inspired online variable recruitment control of fluidic artificial muscles

NASA Astrophysics Data System (ADS)

Jenkins, Tyler E.; Chapman, Edward M.; Bryant, Matthew

2016-12-01

This paper details the creation of a hybrid variable recruitment control scheme for fluidic artificial muscle (FAM) actuators with an emphasis on maximizing system efficiency and switching control performance. Variable recruitment is the process of altering a system’s active number of actuators, allowing operation in distinct force regimes. Previously, FAM variable recruitment was only quantified with offline, manual valve switching; this study addresses the creation and characterization of novel, on-line FAM switching control algorithms. The bio-inspired algorithms are implemented in conjunction with a PID and model-based controller, and applied to a simulated plant model. Variable recruitment transition effects and chatter rejection are explored via a sensitivity analysis, allowing a system designer to weigh tradeoffs in actuator modeling, algorithm choice, and necessary hardware. Variable recruitment is further developed through simulation of a robotic arm tracking a variety of spline position inputs, requiring several levels of actuator recruitment. Switching controller performance is quantified and compared with baseline systems lacking variable recruitment. The work extends current variable recruitment knowledge by creating novel online variable recruitment control schemes, and exploring how online actuator recruitment affects system efficiency and control performance. Key topics associated with implementing a variable recruitment scheme, including the effects of modeling inaccuracies, hardware considerations, and switching transition concerns are also addressed.

Harnessing Electrostatic Forces to Grow Bio-inspired Hierarchical Vascular Networks

NASA Astrophysics Data System (ADS)

Behler, Kristopher; Melrose, Zachary; Schott, Andrew; Wetzel, Eric

2012-02-01

Vascular networks provide a system for fluid distribution. Artificial vascular materials with enhanced properties are currently being developed that could ultimately be integrated into systems reliant upon fluid transport while retaining their structural properties. An uninterrupted and controllable supply of liquid is optimal for many applications such as continual self-healing materials, in-situ delivery of index matched fluids, thermal management and drug delivery systems could benefit from a bio-inspired vascular approach that combines complex network geometries with minimal processing parameters. Two such approaches to induce vascular networks are electrohydrodynamic viscous fingering (EHVF) and electrical treeing (ET). EHVF is a phenomenon that occurs when a low viscosity liquid is forced through a high viscosity fluid or matrix, resulting in branches due to capillary and viscous forces in the high viscosity material. By applying voltages of 0 -- 60 kV, finger diameter is reduced. ET is the result of partial discharges in a dielectric material. In the vicinity of a small diameter electrode, the local electric field is greater than the global dielectric strength, causing a localized, step-wise, breakdown to occur forming a highly branched interconnected structure. ET is a viable method to produce networks on a smaller, micron, scale than the products of the EHVF method.

A Compact VLSI System for Bio-Inspired Visual Motion Estimation.

PubMed

Shi, Cong; Luo, Gang

2018-04-01

This paper proposes a bio-inspired visual motion estimation algorithm based on motion energy, along with its compact very-large-scale integration (VLSI) architecture using low-cost embedded systems. The algorithm mimics motion perception functions of retina, V1, and MT neurons in a primate visual system. It involves operations of ternary edge extraction, spatiotemporal filtering, motion energy extraction, and velocity integration. Moreover, we propose the concept of confidence map to indicate the reliability of estimation results on each probing location. Our algorithm involves only additions and multiplications during runtime, which is suitable for low-cost hardware implementation. The proposed VLSI architecture employs multiple (frame, pixel, and operation) levels of pipeline and massively parallel processing arrays to boost the system performance. The array unit circuits are optimized to minimize hardware resource consumption. We have prototyped the proposed architecture on a low-cost field-programmable gate array platform (Zynq 7020) running at 53-MHz clock frequency. It achieved 30-frame/s real-time performance for velocity estimation on 160 × 120 probing locations. A comprehensive evaluation experiment showed that the estimated velocity by our prototype has relatively small errors (average endpoint error < 0.5 pixel and angular error < 10°) for most motion cases.

Bio-inspired nanocatalysts for the oxygen reduction reaction.

PubMed

Grumelli, Doris; Wurster, Benjamin; Stepanow, Sebastian; Kern, Klaus

2013-01-01

Electrochemical conversions at fuel cell electrodes are complex processes. In particular, the oxygen reduction reaction has substantial overpotential limiting the electrical power output efficiency. Effective and inexpensive catalytic interfaces are therefore essential for increased performance. Taking inspiration from enzymes, earth-abundant metal centres embedded in organic environments present remarkable catalytic active sites. Here we show that these enzyme-inspired centres can be effectively mimicked in two-dimensional metal-organic coordination networks self-assembled on electrode surfaces. Networks consisting of trimesic acid and bis-pyridyl-bispyrimidine coordinating to single iron and manganese atoms on Au(111) effectively catalyse the oxygen reduction and reveal distinctive catalytic activity in alkaline media. These results demonstrate the potential of surface-engineered metal-organic networks for electrocatalytic conversions. Specifically designed coordination complexes at surfaces inspired by enzyme cofactors represent a new class of nanocatalysts with promising applications in electrocatalysis.

Water repellent/wetting characteristics of various bio-inspired morphologies and fluid drag reduction testing research.

PubMed

Luo, Yuehao; Song, Wen; Wang, Xudong

2016-03-01

It is well-known that the bio-inspired sharkskin covering the original pattern has the apparent drag reduction function in the turbulent flowing stations, which can be regarded as "sharkskin effect", and it has progressively been put application into the fluid engineering with obtaining great profits. In this paper, the anisotropic wetting phenomena on sharkskin are discovered, the contact angles and rolling angles on different orientations are not the same. In addition, the hydrodynamic experiments on different sharkskin surfaces are conducted, and the experimental results illustrate that the super-hydrophobic and drag-reducing properties on deformed biological surfaces are improved to some extent compared to the original morphology, which has important significance to expand its practical applications. Copyright © 2015 Elsevier Ltd. All rights reserved.

Converging the capabilities of EAP artificial muscles and the requirements of bio-inspired robotics

NASA Astrophysics Data System (ADS)

Hanson, David F.; White, Victor

2004-07-01

The characteristics of Electro-actuated polymers (EAP) are typically considered inadequate for applications in robotics. But in recent years, there has been both dramatic increases in EAP technological capbilities and reductions in power requirements for actuating bio-inspired robotics. As the two trends continue to converge, one may anticipate that dramatic breakthroughs in biologically inspired robotic actuation will result due to the marraige of these technologies. This talk will provide a snapshot of how EAP actuator scientists and roboticists may work together on a common platform to accelerate the growth of both technologies. To demonstrate this concept of a platform to accelerate this convergence, the authors will discuss their work in the niche application of robotic facial expression. In particular, expressive robots appear to be within the range of EAP actuation, thanks to their low force requirements. Several robots will be shown that demonstrate realistic expressions with dramatically decreased force requirements. Also, detailed descriptions will be given of the engineering innovations that have enabled these robotics advancements-most notably, Structured-Porosity Elastomer Materials (SPEMs). SPEM manufacturing techniques create delicate cell-structures in a variety of elastomers that maintain the high elongation characteristics of the mother material, but because of the porisity, behave as sponge-materials, thus lower the force required to emulate facial expressions to levels output by several extant EAP actuators.

Bio-inspired device: a novel smart MR spring featuring tendril structure

NASA Astrophysics Data System (ADS)

Kaluvan, Suresh; Park, Chun-Yong; Choi, Seung-Bok

2016-01-01

Smart materials such as piezoelectric patches, shape memory alloy, electro and magneto rheological fluid, magnetostrictive materials, etc are involved by far to design intelligent and high performance smart devices like injectors, dental braces, dampers, actuators and sensors. In this paper, an interesting smart device is proposed by inspiring on the structure of the bio climber plant. The key enabling concept of this proposed work is to design the smart spring damper as a helical shaped tendril structure using magneto-rheological (MR) fluid. The proposed smart spring consists of a hollow helical structure filled with MR fluid. The viscosity of the MR fluid decides the damping force of helical shaped smart spring, while the fluid intensity in the vine decides the strength of the tendril in the climber plant. Thus, the proposed smart spring can provide a new concept design of the damper which can be applicable to various damping system industries with tuneable damping force. The proposed smart spring damper has several advantageous such as cost effective, easy implementation compared with the conventional damper. In addition, the proposed spring damper can be easily designed to adapt different damping force levels without any alteration.

Hydrogels from Amorphous Calcium Carbonate and Polyacrylic Acid: Bio-Inspired Materials for "Mineral Plastics".

PubMed

Sun, Shengtong; Mao, Li-Bo; Lei, Zhouyue; Yu, Shu-Hong; Cölfen, Helmut

2016-09-19

Given increasing environmental issues due to the large usage of non-biodegradable plastics based on petroleum, new plastic materials, which are economic, environmentally friendly, and recyclable are in high demand. One feasible strategy is the bio-inspired synthesis of mineral-based hybrid materials. Herein we report a facile route for an amorphous CaCO3 (ACC)-based hydrogel consisting of very small ACC nanoparticles physically cross-linked by poly(acrylic acid). The hydrogel is shapeable, stretchable, and self-healable. Upon drying, the hydrogel forms free-standing, rigid, and transparent objects with remarkable mechanical performance. By swelling in water, the material can completely recover the initial hydrogel state. As a matrix, thermochromism can also be easily introduced. The present hybrid hydrogel may represent a new class of plastic materials, the "mineral plastics". © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Post-capture vibration suppression of spacecraft via a bio-inspired isolation system

NASA Astrophysics Data System (ADS)

Dai, Honghua; Jing, Xingjian; Wang, Yu; Yue, Xiaokui; Yuan, Jianping

2018-05-01

Inspired by the smooth motions of a running kangaroo, a bio-inspired quadrilateral shape (BIQS) structure is proposed to suppress the vibrations of a free-floating spacecraft subject to periodic or impulsive forces, which may be encountered during on-orbit servicing missions. In particular, the BIQS structure is installed between the satellite platform and the capture mechanism. The dynamical model of the BIQS isolation system, i.e. a BIQS structure connecting the platform and the capture mechanism at each side, is established by Lagrange's equations to simulate the post-capture dynamical responses. The BIQS system suffering an impulsive force is dealt with by means of a modified version of Lagrange's equations. Furthermore, the classical harmonic balance method is used to solve the nonlinear dynamical system subject to periodic forces, while for the case under impulsive forces the numerical integration method is adopted. Due to the weightless environment in space, the present BIQS system is essentially an under-constrained dynamical system with one of its natural frequencies being identical to zero. The effects of system parameters, such as the number of layers in BIQS, stiffness, assembly angle, rod length, damping coefficient, masses of satellite platform and capture mechanism, on the isolation performance of the present system are thoroughly investigated. In addition, comparisons between the isolation performances of the presently proposed BIQS isolator and the conventional spring-mass-damper (SMD) isolator are conducted to demonstrate the advantages of the present isolator. Numerical simulations show that the BIQS system has a much better performance than the SMD system under either periodic or impulsive forces. Overall, the present BIQS isolator offers a highly efficient passive way for vibration suppressions of free-floating spacecraft.

Bio-inspired color image enhancement

NASA Astrophysics Data System (ADS)

Meylan, Laurence; Susstrunk, Sabine

2004-06-01

Capturing and rendering an image that fulfills the observer's expectations is a difficult task. This is due to the fact that the signal reaching the eye is processed by a complex mechanism before forming a percept, whereas a capturing device only retains the physical value of light intensities. It is especially difficult to render complex scenes with highly varying luminances. For example, a picture taken inside a room where objects are visible through the windows will not be rendered correctly by a global technique. Either details in the dim room will be hidden in shadow or the objects viewed through the window will be too bright. The image has to be treated locally to resemble more closely to what the observer remembers. The purpose of this work is to develop a technique for rendering images based on human local adaptation. We take inspiration from a model of color vision called Retinex. This model determines the perceived color given spatial relationships of the captured signals. Retinex has been used as a computational model for image rendering. In this article, we propose a new solution inspired by Retinex that is based on a single filter applied to the luminance channel. All parameters are image-dependent so that the process requires no parameter tuning. That makes the method more flexible than other existing ones. The presented results show that our method suitably enhances high dynamic range images.

A High Sensitivity Bio Photosensor for Detecting a Luciferase Bioluminescence

NASA Astrophysics Data System (ADS)

Kameda, Seiji; Moriyama, Yusuke; Noda, Kenichi; Iwata, Atsushi

A high sensitivity CMOS bio photosensor applicable to a bioluminescent assay was developed with a 0.18µm CMOS image sensor (CIS) process. The bio photosensor consisting of a photosensor and a PWM 20bit A/D converter achieved high sensitivity for detecting a extremely low bioluminescence due to a large photodiode area, a long exposure time and the other noise reduction techniques. The bio photosensor chip has a 2×4 sensor array on a 2.45×2.45mm2 die. Experimental results with the bioluminescence showed the chip can detect below 10-5lux luminescence at room temperature and the power consumption is 32µW.

Artificial Roughness Encoding with a Bio-inspired MEMS- based Tactile Sensor Array

PubMed Central

Oddo, Calogero Maria; Beccai, Lucia; Felder, Martin; Giovacchini, Francesco; Carrozza, Maria Chiara

2009-01-01

A compliant 2×2 tactile sensor array was developed and investigated for roughness encoding. State of the art cross shape 3D MEMS sensors were integrated with polymeric packaging providing in total 16 sensitive elements to external mechanical stimuli in an area of about 20 mm2, similarly to the SA1 innervation density in humans. Experimental analysis of the bio-inspired tactile sensor array was performed by using ridged surfaces, with spatial periods from 2.6 mm to 4.1 mm, which were indented with regulated 1N normal force and stroked at constant sliding velocity from 15 mm/s to 48 mm/s. A repeatable and expected frequency shift of the sensor outputs depending on the applied stimulus and on its scanning velocity was observed between 3.66 Hz and 18.46 Hz with an overall maximum error of 1.7%. The tactile sensor could also perform contact imaging during static stimulus indentation. The experiments demonstrated the suitability of this approach for the design of a roughness encoding tactile sensor for an artificial fingerpad. PMID:22412304

Mobile Robots for Localizing Gas Emission Sources on Landfill Sites: Is Bio-Inspiration the Way to Go?

PubMed Central

Hernandez Bennetts, Victor; Lilienthal, Achim J.; Neumann, Patrick P.; Trincavelli, Marco

2011-01-01

Roboticists often take inspiration from animals for designing sensors, actuators, or algorithms that control the behavior of robots. Bio-inspiration is motivated with the uncanny ability of animals to solve complex tasks like recognizing and manipulating objects, walking on uneven terrains, or navigating to the source of an odor plume. In particular the task of tracking an odor plume up to its source has nearly exclusively been addressed using biologically inspired algorithms and robots have been developed, for example, to mimic the behavior of moths, dung beetles, or lobsters. In this paper we argue that biomimetic approaches to gas source localization are of limited use, primarily because animals differ fundamentally in their sensing and actuation capabilities from state-of-the-art gas-sensitive mobile robots. To support our claim, we compare actuation and chemical sensing available to mobile robots to the corresponding capabilities of moths. We further characterize airflow and chemosensor measurements obtained with three different robot platforms (two wheeled robots and one flying micro-drone) in four prototypical environments and show that the assumption of a constant and unidirectional airflow, which is the basis of many gas source localization approaches, is usually far from being valid. This analysis should help to identify how underlying principles, which govern the gas source tracking behavior of animals, can be usefully “translated” into gas source localization approaches that fully take into account the capabilities of mobile robots. We also describe the requirements for a reference application, monitoring of gas emissions at landfill sites with mobile robots, and discuss an engineered gas source localization approach based on statistics as an alternative to biologically inspired algorithms. PMID:22319493

Mobile robots for localizing gas emission sources on landfill sites: is bio-inspiration the way to go?

PubMed

Hernandez Bennetts, Victor; Lilienthal, Achim J; Neumann, Patrick P; Trincavelli, Marco

2011-01-01

Roboticists often take inspiration from animals for designing sensors, actuators, or algorithms that control the behavior of robots. Bio-inspiration is motivated with the uncanny ability of animals to solve complex tasks like recognizing and manipulating objects, walking on uneven terrains, or navigating to the source of an odor plume. In particular the task of tracking an odor plume up to its source has nearly exclusively been addressed using biologically inspired algorithms and robots have been developed, for example, to mimic the behavior of moths, dung beetles, or lobsters. In this paper we argue that biomimetic approaches to gas source localization are of limited use, primarily because animals differ fundamentally in their sensing and actuation capabilities from state-of-the-art gas-sensitive mobile robots. To support our claim, we compare actuation and chemical sensing available to mobile robots to the corresponding capabilities of moths. We further characterize airflow and chemosensor measurements obtained with three different robot platforms (two wheeled robots and one flying micro-drone) in four prototypical environments and show that the assumption of a constant and unidirectional airflow, which is the basis of many gas source localization approaches, is usually far from being valid. This analysis should help to identify how underlying principles, which govern the gas source tracking behavior of animals, can be usefully "translated" into gas source localization approaches that fully take into account the capabilities of mobile robots. We also describe the requirements for a reference application, monitoring of gas emissions at landfill sites with mobile robots, and discuss an engineered gas source localization approach based on statistics as an alternative to biologically inspired algorithms.

Fabrication of bio-inspired nitinol alloy surface with tunable anisotropic wetting and high adhesive ability.

PubMed

Tian, Yan L; Zhao, Yue C; Yang, Cheng J; Wang, Fu J; Liu, Xian P; Jing, Xiu B

2018-10-01

In this paper, micro/nano-scale structures were fabricated on nitinol alloy (NiTi) to realize tunable anisotropic wetting and high adhesive capability. Laser texturing and silanization process are utilized to change the morphological and chemical properties of substrates. It is noted that these treated substrates exhibit the joint characteristics of anisotropic wetting and high adhesive capability. In order to investigate the influences of laser-texturing and silanization processes on NiTi, these surfaces were evaluated using scanning electron microscope (SEM), a white light confocal microscope, X-ray photoelectron spectroscopy (XPS) and goniometer. The relationship between water volume and anisotropic wetting was also established. From the experimental testing, we can obtain the following conclusions: (1) the anisotropic wetting characterized by the difference between the water contact angles (WCAs) in the vertical and parallel directions ranges from 0° to 20.3°, which is far more than the value of natural rice leaves. (2) the water sliding angles (WSAs) kept stable at 180°, successfully mimicking the adhesive ability of rose petals. (3) the silanization process could strengthen the hydrophobicity but weaken anisotropic wetting. These bio-inspired NiTi surfaces have a tremendous potential applications such as microfluidic devices, bio-mimetic materials fabrication and lab on chip. Copyright © 2018 Elsevier Inc. All rights reserved.

Bio-nano interactions detected by nanochannel electrophoresis.

PubMed

Luan, Binquan

2016-08-01

Engineered nanoparticles have been widely used in industry and are present in many consumer products. However, their bio-safeties especially in a long term are largely unknown. Here, a nanochannel-electrophoresis-based method is proposed for detecting the potential bio-nano interactions that may further lead to damages to human health and/or biological environment. Through proof-of-concept molecular dynamics simulations, it was demonstrated that the transport of a protein-nanoparticle complex is very different from that of a protein along. By monitoring the change of ionic currents induced by a transported analyte as well as the transport velocities of the analyte, the complex (with bio-nano interaction) can be clearly distinguished from the protein alone (with no interaction with tested nanoparticles). © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A compact bio-inspired visible/NIR imager for image-guided surgery (Conference Presentation)

NASA Astrophysics Data System (ADS)

Gao, Shengkui; Garcia, Missael; Edmiston, Chris; York, Timothy; Marinov, Radoslav; Mondal, Suman B.; Zhu, Nan; Sudlow, Gail P.; Akers, Walter J.; Margenthaler, Julie A.; Liang, Rongguang; Pepino, Marta; Achilefu, Samuel; Gruev, Viktor

2016-03-01

Inspired by the visual system of the morpho butterfly, we have designed, fabricated, tested and clinically translated an ultra-sensitive, light weight and compact imaging sensor capable of simultaneously capturing near infrared (NIR) and visible spectrum information. The visual system of the morpho butterfly combines photosensitive cells with spectral filters at the receptor level. The spectral filters are realized by alternating layers of high and low dielectric constant, such as air and cytoplasm. We have successfully mimicked this concept by integrating pixelated spectral filters, realized by alternating silicon dioxide and silicon nitrate layers, with an array of CCD detectors. There are four different types of pixelated spectral filters in the imaging plane: red, green, blue and NIR. The high optical density (OD) of all spectral filters (OD>4) allow for efficient rejections of photons from unwanted bands. The single imaging chip weighs 20 grams with form factor of 5mm by 5mm. The imaging camera is integrated with a goggle display system. A tumor targeted agent, LS301, is used to identify all spontaneous tumors in a transgenic PyMT murine model of breast cancer. The imaging system achieved sensitivity of 98% and selectivity of 95%. We also used our imaging sensor to locate sentinel lymph nodes (SLNs) in patients with breast cancer using indocyanine green tracer. The surgeon was able to identify 100% of SLNs when using our bio-inspired imaging system, compared to 93% when using information from the lymphotropic dye and 96% when using information from the radioactive tracer.

Drawing inspiration from biological optical systems

NASA Astrophysics Data System (ADS)

Wolpert, H. D.

2009-08-01

Bio-Mimicking/Bio-Inspiration: How can we not be inspired by Nature? Life has evolved on earth over the last 3.5 to 4 billion years. Materials formed during this time were not toxic; they were created at low temperatures and low pressures unlike many of the materials developed today. The natural materials formed are self-assembled, multifunctional, nonlinear, complex, adaptive, self-repairing and biodegradable. The designs that failed are fossils. Those that survived are the success stories. Natural materials are mostly formed from organics, inorganic crystals and amorphous phases. The materials make economic sense by optimizing the design of the structures or systems to meet multiple needs. We constantly "see" many similar strategies in approaches, between man and nature, but we seldom look at the details of natures approaches. The power of image processing, in many of natures creatures, is a detail that is often overlooked. Seldon does the engineer interact with the biologist and learn what nature has to teach us. The variety and complexity of biological materials and the optical systems formed should inspire us.

Detection of proteins using a colorimetric bio-barcode assay.

PubMed

Nam, Jwa-Min; Jang, Kyung-Jin; Groves, Jay T

2007-01-01

The colorimetric bio-barcode assay is a red-to-blue color change-based protein detection method with ultrahigh sensitivity. This assay is based on both the bio-barcode amplification method that allows for detecting miniscule amount of targets with attomolar sensitivity and gold nanoparticle-based colorimetric DNA detection method that allows for a simple and straightforward detection of biomolecules of interest (here we detect interleukin-2, an important biomarker (cytokine) for many immunodeficiency-related diseases and cancers). The protocol is composed of the following steps: (i) conjugation of target capture molecules and barcode DNA strands onto silica microparticles, (ii) target capture with probes, (iii) separation and release of barcode DNA strands from the separated probes, (iv) detection of released barcode DNA using DNA-modified gold nanoparticle probes and (v) red-to-blue color change analysis with a graphic software. Actual target detection and quantification steps with premade probes take approximately 3 h (whole protocol including probe preparations takes approximately 3 days).

The Difference Se Makes: A Bio-Inspired Dppf-Supported Nickel Selenolate Complex Boosts Dihydrogen Evolution with High Oxygen Tolerance.

PubMed

Pan, Zhong-Hua; Tao, Yun-Wen; He, Quan-Feng; Wu, Qiao-Yu; Cheng, Li-Ping; Wei, Zhan-Hua; Wu, Ji-Huai; Lin, Jin-Qing; Sun, Di; Zhang, Qi-Chun; Tian, Dan; Luo, Geng-Geng

2018-06-12

Inspired by the metal active sites of [NiFeSe]-hydrogenases, a dppf-supported nickel(II) selenolate complex (dppf=1,1'-bis(diphenylphosphino)ferrocene) shows high catalytic activity for electrochemical proton reduction with a remarkable enzyme-like H 2 evolution turnover frequency (TOF) of 7838 s -1 under an Ar atmosphere, which markedly surpasses the activity of a dppf-supported nickel(II) thiolate analogue with a low TOF of 600 s -1 . A combined study of electrochemical experiments and DFT calculations shed light on the catalytic process, suggesting that selenium atom as a bio-inspired proton relay plays a key role in proton exchange and enhancing catalytic activity of H 2 production. For the first time, this type of Ni selenolate-containing electrocatalyst displays a high degree of O 2 and H 2 tolerance. Our results should encourage the development of the design of highly efficient oxygen-tolerant Ni selenolate molecular catalysts. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Hierarchical biointerfaces assembled by leukocyte-inspired particles for specifically recognizing cancer cells.

PubMed

Meng, Jingxin; Liu, Hongliang; Liu, Xueli; Yang, Gao; Zhang, Pengchao; Wang, Shutao; Jiang, Lei

2014-09-24

By mimicking certain biochemical and physical attributes of biological cells, bio-inspired particles have attracted great attention for potential biomedical applications based on cell-like biological functions. Inspired by leukocytes, hierarchical biointerfaces are designed and prepared based on specific molecules-modified leukocyte-inspired particles. These biointerfaces can efficiently recognize cancer cells from whole blood samples through the synergistic effect of molecular recognition and topographical interaction. Compared to flat, mono-micro or nano-biointerfaces, these micro/nano hierarchical biointerfaces are better able to promote specific recognition interactions, resulting in an enhanced cell-capture efficiency. It is anticipated that this study may provide promising guidance to develop new bio-inspired hierarchical biointerfaces for biomedical applications. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Distributed Synchronization Technique for OFDMA-Based Wireless Mesh Networks Using a Bio-Inspired Algorithm

PubMed Central

Kim, Mi Jeong; Maeng, Sung Joon; Cho, Yong Soo

2015-01-01

In this paper, a distributed synchronization technique based on a bio-inspired algorithm is proposed for an orthogonal frequency division multiple access (OFDMA)-based wireless mesh network (WMN) with a time difference of arrival. The proposed time- and frequency-synchronization technique uses only the signals received from the neighbor nodes, by considering the effect of the propagation delay between the nodes. It achieves a fast synchronization with a relatively low computational complexity because it is operated in a distributed manner, not requiring any feedback channel for the compensation of the propagation delays. In addition, a self-organization scheme that can be effectively used to construct 1-hop neighbor nodes is proposed for an OFDMA-based WMN with a large number of nodes. The performance of the proposed technique is evaluated with regard to the convergence property and synchronization success probability using a computer simulation. PMID:26225974

Distributed Synchronization Technique for OFDMA-Based Wireless Mesh Networks Using a Bio-Inspired Algorithm.

PubMed

Kim, Mi Jeong; Maeng, Sung Joon; Cho, Yong Soo

2015-07-28

In this paper, a distributed synchronization technique based on a bio-inspired algorithm is proposed for an orthogonal frequency division multiple access (OFDMA)-based wireless mesh network (WMN) with a time difference of arrival. The proposed time- and frequency-synchronization technique uses only the signals received from the neighbor nodes, by considering the effect of the propagation delay between the nodes. It achieves a fast synchronization with a relatively low computational complexity because it is operated in a distributed manner, not requiring any feedback channel for the compensation of the propagation delays. In addition, a self-organization scheme that can be effectively used to construct 1-hop neighbor nodes is proposed for an OFDMA-based WMN with a large number of nodes. The performance of the proposed technique is evaluated with regard to the convergence property and synchronization success probability using a computer simulation.

Direct fabrication of bio-inspired gecko-like geometries with vat polymerization additive manufacturing method

NASA Astrophysics Data System (ADS)

Davoudinejad, A.; Ribo, M. M.; Pedersen, D. B.; Islam, A.; Tosello, G.

2018-08-01

Functional surfaces have proven their potential to solve many engineering problems, attracting great interest among the scientific community. Bio-inspired multi-hierarchical micro-structures grant the surfaces with new properties, such as hydrophobicity, adhesion, unique optical properties and so on. The geometry and fabrication of these surfaces are still under research. In this study, the feasibility of using direct fabrication of microscale features by additive manufacturing (AM) processes was investigated. The investigation was carried out using a specifically designed vat photopolymerization AM machine-tool suitable for precision manufacturing at the micro dimensional scale which has previously been developed, built and validated at the Technical University of Denmark. It was shown that it was possible to replicate a simplified surface inspired by the Tokay gecko, the geometry was previously designed and replicated by a complex multi-step micromanufacturing method extracted from the literature and used as benchmark. Ultimately, the smallest printed features were analyzed by conducting a sensitivity analysis to obtain the righteous parameters in terms of layer thickness and exposure time. Moreover, two more intricate designs were fabricated with the same parameters to assess the surfaces functionality by its wettability. The surface with increased density and decreased feature size showed a water contact angle (CA) of 124°  ±  0.10°, agreeing with the Cassie–Baxter model. These results indicate the possibility of using precision AM for a rapid, easy and reliable fabrication method for functional surfaces.

Anti-icing property of bio-inspired micro-structure superhydrophobic surfaces and heat transfer model

NASA Astrophysics Data System (ADS)

Liu, Yan; Li, Xinlin; Jin, Jingfu; Liu, Jiaan; Yan, Yuying; Han, Zhiwu; Ren, Luquan

2017-04-01

Ice accumulation is a thorny problem which may inflict serious damage even disasters in many areas, such as aircraft, power line maintenance, offshore oil platform and locators of ships. Recent researches have shed light on some promising bio-inspired anti-icing strategies to solve this problem. Inspired by typical plant surfaces with super-hydrophobic character such as lotus leaves and rose petals, structured superhydrophobic surface are prepared to discuss the anti-icing property. 7075 Al alloy, an extensively used materials in aircrafts and marine vessels, is employed as the substrates. As-prepared surfaces are acquired by laser processing after being modified by stearic acid for 1 h at room temperature. The surface morphology, chemical composition and wettability are characterized by means of SEM, XPS, Fourier transform infrared (FTIR) spectroscopy and contact angle measurements. The morphologies of structured as-prepared samples include round hump, square protuberance and mountain-range-like structure, and that the as-prepared structured surfaces shows an excellent superhydrophobic property with a WCA as high as 166 ± 2°. Furthermore, the anti-icing property of as-prepared surfaces was tested by a self-established apparatus, and the crystallization process of a cooling water on the sample was recorded. More importantly, we introduced a model to analyze heat transfer process between the droplet and the structured surfaces. This study offers an insight into understanding the heat transfer process of the superhydrophobic surface, so as to further research about its unique property against ice accumulation.

Bio-inspired grasp control in a robotic hand with massive sensorial input.

PubMed

Ascari, Luca; Bertocchi, Ulisse; Corradi, Paolo; Laschi, Cecilia; Dario, Paolo

2009-02-01

The capability of grasping and lifting an object in a suitable, stable and controlled way is an outstanding feature for a robot, and thus far, one of the major problems to be solved in robotics. No robotic tools able to perform an advanced control of the grasp as, for instance, the human hand does, have been demonstrated to date. Due to its capital importance in science and in many applications, namely from biomedics to manufacturing, the issue has been matter of deep scientific investigations in both the field of neurophysiology and robotics. While the former is contributing with a profound understanding of the dynamics of real-time control of the slippage and grasp force in the human hand, the latter tries more and more to reproduce, or take inspiration by, the nature's approach, by means of hardware and software technology. On this regard, one of the major constraints robotics has to overcome is the real-time processing of a large amounts of data generated by the tactile sensors while grasping, which poses serious problems to the available computational power. In this paper a bio-inspired approach to tactile data processing has been followed in order to design and test a hardware-software robotic architecture that works on the parallel processing of a large amount of tactile sensing signals. The working principle of the architecture bases on the cellular nonlinear/neural network (CNN) paradigm, while using both hand shape and spatial-temporal features obtained from an array of microfabricated force sensors, in order to control the sensory-motor coordination of the robotic system. Prototypical grasping tasks were selected to measure the system performances applied to a computer-interfaced robotic hand. Successful grasps of several objects, completely unknown to the robot, e.g. soft and deformable objects like plastic bottles, soft balls, and Japanese tofu, have been demonstrated.

Development of multifunctional materials exhibiting distributed sensing and actuation inspired by fish

NASA Astrophysics Data System (ADS)

Philen, Michael

2011-04-01

This manuscript is an overview of the research that is currently being performed as part of a 2009 NSF Office of Emerging Frontiers in Research and Innnovation (EFRI) grant on BioSensing and BioActuation (BSBA). The objectives of this multi-university collaborative research are to achieve a greater understanding of the hierarchical organization and structure of the sensory, muscular, and control systems of fish, and to develop advanced biologically-inspired material systems having distributed sensing, actuation, and intelligent control. New experimental apparatus have been developed for performing experiments involving live fish and robotic devices, and new bio-inspired haircell sensors and artificial muscles are being developed using carbonaceous nanomaterials, bio-derived molecules, and composite technology. Results demonstrating flow sensing and actuation are presented.

The actuation of microflaps inspired by shark scales deeply embedded in a boundary layer

NASA Astrophysics Data System (ADS)

Morris, Jackson; Lang, Amy; Hubner, Paul

2016-11-01

Thanks to millions of years of natural selection, sharks have evolved to become quick apex predators. Shark skin is made up of microscopic scales on the order of 0.2 mm in size. This array of scales is hypothesized to be a flow control mechanism where individual scales are capable of being passively actuated by reversed flow in water due to their preferential orientation to attached flow. Previous research has proven shark skin to reduce flow separation in water, which would result in lower pressure drag. We believe shark scales are strategically sized to interact with the lower 5 percent of the boundary layer, where reversed flow occurs close to the wall. To test the capability of micro-flaps to be actuated in air various sets of flaps, inspired by shark scale geometry, were rapidly prototyped. These microflaps were tested in a low-speed wind tunnel at various flow speeds and boundary layer thicknesses. Boundary layer flow conditions were measured using a hot-wire probe and microflap actuation was observed. Microflap actuation in airflow would mean that this bio-inspired separation control mechanism found on shark skin has potential application for aircraft. Boeing.

Bio-Inspired Aggregation Control of Carbon Nanotubes for Ultra-Strong Composites

PubMed Central

Han, Yue; Zhang, Xiaohua; Yu, Xueping; Zhao, Jingna; Li, Shan; Liu, Feng; Gao, Peng; Zhang, Yongyi; Zhao, Tong; Li, Qingwen

2015-01-01

High performance nanocomposites require well dispersion and high alignment of the nanometer-sized components, at a high mass or volume fraction as well. However, the road towards such composite structure is severely hindered due to the easy aggregation of these nanometer-sized components. Here we demonstrate a big step to approach the ideal composite structure for carbon nanotube (CNT) where all the CNTs were highly packed, aligned, and unaggregated, with the impregnated polymers acting as interfacial adhesions and mortars to build up the composite structure. The strategy was based on a bio-inspired aggregation control to limit the CNT aggregation to be sub 20–50 nm, a dimension determined by the CNT growth. After being stretched with full structural relaxation in a multi-step way, the CNT/polymer (bismaleimide) composite yielded super-high tensile strengths up to 6.27–6.94 GPa, more than 100% higher than those of carbon fiber/epoxy composites, and toughnesses up to 117–192 MPa. We anticipate that the present study can be generalized for developing multifunctional and smart nanocomposites where all the surfaces of nanometer-sized components can take part in shear transfer of mechanical, thermal, and electrical signals. PMID:26098627

The tubercles on humpback whales' flippers: application of bio-inspired technology.

PubMed

Fish, Frank E; Weber, Paul W; Murray, Mark M; Howle, Laurens E

2011-07-01

The humpback whale (Megaptera novaeangliae) is exceptional among the large baleen whales in its ability to undertake aquabatic maneuvers to catch prey. Humpback whales utilize extremely mobile, wing-like flippers for banking and turning. Large rounded tubercles along the leading edge of the flipper are morphological structures that are unique in nature. The tubercles on the leading edge act as passive-flow control devices that improve performance and maneuverability of the flipper. Experimental analysis of finite wing models has demonstrated that the presence of tubercles produces a delay in the angle of attack until stall, thereby increasing maximum lift and decreasing drag. Possible fluid-dynamic mechanisms for improved performance include delay of stall through generation of a vortex and modification of the boundary layer, and increase in effective span by reduction of both spanwise flow and strength of the tip vortex. The tubercles provide a bio-inspired design that has commercial viability for wing-like structures. Control of passive flow has the advantages of eliminating complex, costly, high-maintenance, and heavy control mechanisms, while improving performance for lifting bodies in air and water. The tubercles on the leading edge can be applied to the design of watercraft, aircraft, ventilation fans, and windmills.

Biomimetic Sniffing Improves the Detection Performance of a 3D Printed Nose of a Dog and a Commercial Trace Vapor Detector

NASA Astrophysics Data System (ADS)

Staymates, Matthew E.; Maccrehan, William A.; Staymates, Jessica L.; Kunz, Roderick R.; Mendum, Thomas; Ong, Ta-Hsuan; Geurtsen, Geoffrey; Gillen, Greg J.; Craven, Brent A.

2016-12-01

Unlike current chemical trace detection technology, dogs actively sniff to acquire an odor sample. Flow visualization experiments with an anatomically-similar 3D printed dog’s nose revealed the external aerodynamics during canine sniffing, where ventral-laterally expired air jets entrain odorant-laden air toward the nose, thereby extending the “aerodynamic reach” for inspiration of otherwise inaccessible odors. Chemical sampling and detection experiments quantified two modes of operation with the artificial nose-active sniffing and continuous inspiration-and demonstrated an increase in odorant detection by a factor of up to 18 for active sniffing. A 16-fold improvement in detection was demonstrated with a commercially-available explosives detector by applying this bio-inspired design principle and making the device “sniff” like a dog. These lessons learned from the dog may benefit the next-generation of vapor samplers for explosives, narcotics, pathogens, or even cancer, and could inform future bio-inspired designs for optimized sampling of odor plumes.

Biomimetic Sniffing Improves the Detection Performance of a 3D Printed Nose of a Dog and a Commercial Trace Vapor Detector

PubMed Central

Staymates, Matthew E.; MacCrehan, William A.; Staymates, Jessica L.; Kunz, Roderick R.; Mendum, Thomas; Ong, Ta-Hsuan; Geurtsen, Geoffrey; Gillen, Greg J.; Craven, Brent A.

2016-01-01

Unlike current chemical trace detection technology, dogs actively sniff to acquire an odor sample. Flow visualization experiments with an anatomically-similar 3D printed dog’s nose revealed the external aerodynamics during canine sniffing, where ventral-laterally expired air jets entrain odorant-laden air toward the nose, thereby extending the “aerodynamic reach” for inspiration of otherwise inaccessible odors. Chemical sampling and detection experiments quantified two modes of operation with the artificial nose-active sniffing and continuous inspiration-and demonstrated an increase in odorant detection by a factor of up to 18 for active sniffing. A 16-fold improvement in detection was demonstrated with a commercially-available explosives detector by applying this bio-inspired design principle and making the device “sniff” like a dog. These lessons learned from the dog may benefit the next-generation of vapor samplers for explosives, narcotics, pathogens, or even cancer, and could inform future bio-inspired designs for optimized sampling of odor plumes. PMID:27906156

Fusion of nacre, mussel, and lotus leaf: bio-inspired graphene composite paper with multifunctional integration.

PubMed

Zhong, Da; Yang, Qinglin; Guo, Lin; Dou, Shixue; Liu, Kesong; Jiang, Lei

2013-07-07

Multifunctional integration is an inherent characteristic for biological materials with multiscale structures. Learning from nature is an effective approach for scientists and engineers to construct multifunctional materials. In nature, mollusks (abalone), mussels, and the lotus have evolved different and optimized solutions to survive. Here, bio-inspired multifunctional graphene composite paper was fabricated in situ through the fusion of the different biological solutions from nacre (brick-and-mortar structure), mussel adhesive protein (adhesive property and reducing character), and the lotus leaf (self-cleaning effect). Owing to the special properties (self-polymerization, reduction, and adhesion), dopamine could be simultaneously used as a reducing agent for graphene oxide and as an adhesive, similar to the mortar in nacre, to crosslink the adjacent graphene. The resultant nacre-like graphene paper exhibited stable superhydrophobicity, self-cleaning, anti-corrosion, and remarkable mechanical properties underwater.

BATMAV: a 2-DOF bio-inspired flapping flight platform

NASA Astrophysics Data System (ADS)

Bunget, Gheorghe; Seelecke, Stefan

2010-04-01

Due to the availability of small sensors, Micro-Aerial Vehicles (MAVs) can be used for detection missions of biological, chemical and nuclear agents. Traditionally these devices used fixed or rotary wings, actuated with electric DC motortransmission, a system which brings the disadvantage of a heavier platform. The overall objective of the BATMAV project is to develop a biologically inspired bat-like MAV with flexible and foldable wings for flapping flight. This paper presents a flight platform that features bat-inspired wings which are able to actively fold their elbow joints. A previous analysis of the flight physics for small birds, bats and large insects, revealed that the mammalian flight anatomy represents a suitable flight platform that can be actuated efficiently using Shape Memory Alloy (SMA) artificial-muscles. A previous study of the flight styles in bats based on the data collected by Norberg [1] helped to identify the required joint angles as relevant degrees of freedom for wing actuation. Using the engineering theory of robotic manipulators, engineering kinematic models of wings with 2 and 3-DOFs were designed to mimic the wing trajectories of the natural flier Plecotus auritus. Solid models of the bat-like skeleton were designed based on the linear and angular dimensions resulted from the kinematic models. This structure of the flight platform was fabricated using rapid prototyping technologies and assembled to form a desktop prototype with 2-DOFs wings. Preliminary flapping test showed suitable trajectories for wrist and wingtip that mimic the flapping cycle of the natural flyer.

Bio-inspired algorithms applied to molecular docking simulations.

PubMed

Heberlé, G; de Azevedo, W F

2011-01-01

Nature as a source of inspiration has been shown to have a great beneficial impact on the development of new computational methodologies. In this scenario, analyses of the interactions between a protein target and a ligand can be simulated by biologically inspired algorithms (BIAs). These algorithms mimic biological systems to create new paradigms for computation, such as neural networks, evolutionary computing, and swarm intelligence. This review provides a description of the main concepts behind BIAs applied to molecular docking simulations. Special attention is devoted to evolutionary algorithms, guided-directed evolutionary algorithms, and Lamarckian genetic algorithms. Recent applications of these methodologies to protein targets identified in the Mycobacterium tuberculosis genome are described.

Atomistic simulation on the plastic deformation and fracture of bio-inspired graphene/Ni nanocomposites

NASA Astrophysics Data System (ADS)

Yang, Zhenyu; Wang, Dandan; Lu, Zixing; Hu, Wenjun

2016-11-01

Molecular dynamics simulations were performed to investigate the plastic deformation and fracture behaviors of bio-inspired graphene/metal nanocomposites, which have a "brick-and-mortar" nanostructure, consisting of hard graphene single-layers embedded in a soft Ni matrix. The plastic deformation mechanisms of the nanocomposites were analyzed as well as their effects on the mechanical properties with various geometrical variations. It was found that the strength and ductility of the metal matrix can be highly enhanced with the addition of the staggered graphene layers, and the plastic deformation can be attributed to the interfacial sliding, dislocation nucleation, and cracks' combination. The strength of the nanocomposites strongly depends on the length scale of the nanostructure and the interlayer distance as well. In addition, slip at the interface releases the stress in graphene layers, leading to the stress distribution on the graphene more uniform. The present results are expected to contribute to the design of the nanolayered graphene/metal composites with high performance.

On-line high-speed rail defect detection.

DOT National Transportation Integrated Search

2004-10-01

This report presents the results of phase 2 of the project On-line high-speed rail defect detection aimed at improving the reliability and the speed of current defect detection in rails. Ultrasonic guided waves, traveling in the rail running di...

A bio-image sensor for simultaneous detection of multi-neurotransmitters.

PubMed

Lee, You-Na; Okumura, Koichi; Horio, Tomoko; Iwata, Tatsuya; Takahashi, Kazuhiro; Hattori, Toshiaki; Sawada, Kazuaki

2018-03-01

We report here a new bio-image sensor for simultaneous detection of spatial and temporal distribution of multi-neurotransmitters. It consists of multiple enzyme-immobilized membranes on a 128 × 128 pixel array with read-out circuit. Apyrase and acetylcholinesterase (AChE), as selective elements, are used to recognize adenosine 5'-triphosphate (ATP) and acetylcholine (ACh), respectively. To enhance the spatial resolution, hydrogen ion (H + ) diffusion barrier layers are deposited on top of the bio-image sensor and demonstrated their prevention capability. The results are used to design the space among enzyme-immobilized pixels and the null H + sensor to minimize the undesired signal overlap by H + diffusion. Using this bio-image sensor, we can obtain H + diffusion-independent imaging of concentration gradients of ATP and ACh in real-time. The sensing characteristics, such as sensitivity and detection of limit, are determined experimentally. With the proposed bio-image sensor the possibility exists for customizable monitoring of the activities of various neurochemicals by using different kinds of proton-consuming or generating enzymes. Copyright © 2017 Elsevier B.V. All rights reserved.

Star-shaped polymers of bio-inspired algae core and poly(acrylamide) and poly(acrylic acid) as arms in dissolution of silica/silicate.

PubMed

Chauhan, Kalpana; Patiyal, Priyanka; Chauhan, Ghanshyam S; Sharma, Praveen

2014-06-01

Silica, in natural waters (due to weathering of rocks) decreases system performance in water processing industry due to scaling. In view of that, the present work involves the synthesis of novel green star shaped additives of algae core (a bio-inspired material as diatom maintains silicic acid equilibrium in sea water) as silica polymerization inhibitors. Star shaped materials with bio-inspired core and poly(acrylamide) [poly(AAm)] and poly(acrylic acid) [poly(AAc)] arms were synthesized by economical green approach. The proficiency was evaluated in 'mini lab' scale for the synthesized APAAm (Algae-g-poly(AAm)) and APAAc (Algae-g-poly(AAc)) dendrimers (star shaped) in colloidal silica mitigation/inhibition at 35 °C and 55 °C. Synthesized dendrimers were equally proficient in silica inhibition at 12 h and maintains ≥450 ppm soluble silica. However, APAAm dendrimers of generation 0 confirmed better results (≈300 ppm) in contrast to APAAc dendrimers in silica inhibition at 55 °C. Additionally, dendrimers also worked as a nucleator for heterogeneous polymerization to inhibit silica homo-polymerization. APAAm dendrimer test set showed no silica deposit for more than 10 days of inhibition. EDX characterization results support nucleator mechanism with Si content of 6.97%-10.98% by weight in silica deposits (SiO2-APAAm dendrimer composites). Copyright © 2014 Elsevier Ltd. All rights reserved.

Development of a bio-inspired UAV perching system

NASA Astrophysics Data System (ADS)

Xie, Pu

of animals and human arms approaching to a fixed or moving target for grasping or capturing. The autonomous flight control was also implemented through a PID controller. Autonomous flight performance was proved through simulation in SimMechanics. Finally, the prototyping of our designs were conducted in different generations of our bio-inspired UAV perching system, which include the leg prototype, gripper prototype, and system prototype. Both the machined prototype and 3D printed prototype were tried. The performance of these prototypes was tested through experiments.

Three-Dimensional Path Planning for Uninhabited Combat Aerial Vehicle Based on Predator-Prey Pigeon-Inspired Optimization in Dynamic Environment.

PubMed

Zhang, Bo; Duan, Haibin

2017-01-01

Three-dimension path planning of uninhabited combat aerial vehicle (UCAV) is a complicated optimal problem, which mainly focused on optimizing the flight route considering the different types of constrains under complex combating environment. A novel predator-prey pigeon-inspired optimization (PPPIO) is proposed to solve the UCAV three-dimension path planning problem in dynamic environment. Pigeon-inspired optimization (PIO) is a new bio-inspired optimization algorithm. In this algorithm, map and compass operator model and landmark operator model are used to search the best result of a function. The prey-predator concept is adopted to improve global best properties and enhance the convergence speed. The characteristics of the optimal path are presented in the form of a cost function. The comparative simulation results show that our proposed PPPIO algorithm is more efficient than the basic PIO, particle swarm optimization (PSO), and different evolution (DE) in solving UCAV three-dimensional path planning problems.

Design, synthesis and characterization of a hexapeptide bio-inspired by acetylcholinesterase and its interaction with pesticide dichlorvos.

PubMed

dos Santos, Glauco Pilon; da Silva, Bianca Ferreira; Garrido, Saulo Santesso; Mascini, Marcello; Yamanaka, Hideko

2014-01-07

This paper describes the molecular modeling design, synthesis and characterization of a new bio-inspired hexapeptide of acetylcholinesterase enzyme and its interaction with the organophosphate pesticide dichlorvos monitored by UV-Vis spectroscopy and mass spectrometry. This strategy can contribute to the development of synthetic receptors to be coupled to biosensor transducers, avoiding the issues associated with proteins such as low stability under different pH and temperature conditions and high production cost. The resulting data of this work indicate a strong interaction between the pesticide dichlorvos and the hexapeptide (NH3(+)-Glu-His-Gly-Gly-Pro-Ser-COO(-)) with a binding constant of 4.10 × 10(5) M(-1) and the formation of an adduct by covalent binding on the serine residue from the hexapeptide.

A new bio-inspired stimulator to suppress hyper-synchronized neural firing in a cortical network.

PubMed

Amiri, Masoud; Amiri, Mahmood; Nazari, Soheila; Faez, Karim

2016-12-07

Hyper-synchronous neural oscillations are the character of several neurological diseases such as epilepsy. On the other hand, glial cells and particularly astrocytes can influence neural synchronization. Therefore, based on the recent researches, a new bio-inspired stimulator is proposed which basically is a dynamical model of the astrocyte biophysical model. The performance of the new stimulator is investigated on a large-scale, cortical network. Both excitatory and inhibitory synapses are also considered in the simulated spiking neural network. The simulation results show that the new stimulator has a good performance and is able to reduce recurrent abnormal excitability which in turn avoids the hyper-synchronous neural firing in the spiking neural network. In this way, the proposed stimulator has a demand controlled characteristic and is a good candidate for deep brain stimulation (DBS) technique to successfully suppress the neural hyper-synchronization. Copyright © 2016 Elsevier Ltd. All rights reserved.

Bio-Functional Au/Si Nanorods for Pathogen Detection

USDA-ARS?s Scientific Manuscript database

Technical Abstract Nanotechnology applications for food safety and biosecurity, especially development of nanoscale sensors for foodborne pathogen measurement are emerging. A novel bio-functional nanosensor for Salmonella detection was developed using hetero-nanorods. The silica nanorods were fabr...

Holarchical Systems and Emotional Holons : Biologically-Inspired System Designs for Control of Autonomous Aerial Vehicles

NASA Technical Reports Server (NTRS)

Ippolito, Corey; Plice, Laura; Pisanich, Greg

2003-01-01

The BEES (Bio-inspired Engineering for Exploration Systems) for Mars project at NASA Ames Research Center has the goal of developing bio-inspired flight control strategies to enable aerial explorers for Mars scientific investigations. This paper presents a summary of our ongoing research into biologically inspired system designs for control of unmanned autonomous aerial vehicle communities for Mars exploration. First, we present cooperative design considerations for robotic explorers based on the holarchical nature of biological systems and communities. Second, an outline of an architecture for cognitive decision making and control of individual robotic explorers is presented, modeled after the emotional nervous system of cognitive biological systems. Keywords: Holarchy, Biologically Inspired, Emotional UAV Flight Control

Bio-inspired, colorful, flexible, defrostable light-scattering hybrid films for the effective distribution of LED light.

PubMed

An, Seongpil; Jo, Hong Seok; Kim, Yong Il; Song, Kyo Yong; Kim, Min-Woo; Lee, Kyu Bum; Yarin, Alexander L; Yoon, Sam S

2017-07-06

Bioluminescent jellyfish has a unique structure derived from fiber/polymer interfaces that is advantageous for effective light scattering in the dark, deep sea water. Herein, we demonstrate the fabrication of bio-inspired hybrid films by mimicry of the jellyfish's structure, leading to excellent light-scattering performance and defrosting capability. A haze value reaching 59.3% and a heating temperature of up to 292 °C were achieved with the films. Accordingly, the developed surface constitutes an attractive optical device for lighting applications, especially for street or vehicle luminaries for freezing Arctic-climate countries. The morphological details of the hybrid films were revealed by scanning electron microscopy. The light-scattering properties of these films were examined by ultraviolet-visible-infrared spectrophotometry and anti-glare effect analyses. The defrosting performance of the hybrid films was evaluated via heating tests and infra-red observations.

Bio-inspired metal-coordinate hydrogels with programmable viscoelastic material functions controlled by longwave UV light.

PubMed

Grindy, Scott C; Holten-Andersen, Niels

2017-06-07

Control over the viscoelastic mechanical properties of hydrogels intended for use as biomedical materials has long been a goal of soft matter scientists. Recent research has shown that materials made from polymers with reversibly associating transient crosslinks are a promising strategy for controlling viscoelasticity in hydrogels, for example leading to systems with precisely tunable mechanical energy-dissipation. We and others have shown that bio-inspired histidine:transition metal ion complexes allow highly precise and tunable control over the viscoelastic properties of transient network hydrogels. In this paper, we extend the design of these hydrogels such that their viscoelastic properties respond to longwave UV radiation. We show that careful selection of the histidine:transition metal ion crosslink mixtures allows unique control over pre- and post-UV viscoelastic properties. We anticipate that our strategy for controlling stimuli-responsive viscoelastic properties will aid biomedical materials scientists in the development of soft materials with specific stress-relaxing or energy-dissipating properties.

Novel High Integrity Bio-Inspired Systems with On-Line Self-Test and Self-Repair Properties

NASA Astrophysics Data System (ADS)

Samie, Mohammad; Dragffy, Gabriel; Pipe, Tony

2011-08-01

Since the beginning of life nature has been developing some remarkable solutions to the problem of creating reliable systems that can operate under difficult environmental and fault conditions. Yet, no matter how sophisticated our systems are, we are still unable to match the high degree of reliability that biological organisms posses. Since the early '90s attempts have been made to adapt biological properties and processes to the design of electronic systems but the results have always been unduly complex.This paper, proposes a novel model using a radically new approach to construct highly reliable electronic systems with online fault repair properties. It uses the characteristics and behaviour of unicellular bacteria and bacterial communities to achieve this. The result is a configurable bio-inspired cellular array architecture that, with built-in self-diagnostic and self-repair properties, can implement any application specific electronic system but is particularly suited for safety critical environments, such as space.

Bio-inspired optical rotation sensor

NASA Astrophysics Data System (ADS)

O'Carroll, David C.; Shoemaker, Patrick A.; Brinkworth, Russell S. A.

2007-01-01

Traditional approaches to calculating self-motion from visual information in artificial devices have generally relied on object identification and/or correlation of image sections between successive frames. Such calculations are computationally expensive and real-time digital implementation requires powerful processors. In contrast flies arrive at essentially the same outcome, the estimation of self-motion, in a much smaller package using vastly less power. Despite the potential advantages and a few notable successes, few neuromorphic analog VLSI devices based on biological vision have been employed in practical applications to date. This paper describes a hardware implementation in aVLSI of our recently developed adaptive model for motion detection. The chip integrates motion over a linear array of local motion processors to give a single voltage output. Although the device lacks on-chip photodetectors, it includes bias circuits to use currents from external photodiodes, and we have integrated it with a ring-array of 40 photodiodes to form a visual rotation sensor. The ring configuration reduces pattern noise and combined with the pixel-wise adaptive characteristic of the underlying circuitry, permits a robust output that is proportional to image rotational velocity over a large range of speeds, and is largely independent of either mean luminance or the spatial structure of the image viewed. In principle, such devices could be used as an element of a velocity-based servo to replace or augment inertial guidance systems in applications such as mUAVs.

Bio-inspired dental fillings

NASA Astrophysics Data System (ADS)

Deyhle, Hans; Bunk, Oliver; Buser, Stefan; Krastl, Gabriel; Zitzmann, Nicola U.; Ilgenstein, Bernd; Beckmann, Felix; Pfeiffer, Franz; Weiger, Roland; Müller, Bert

2009-08-01

Human teeth are anisotropic composites. Dentin as the core material of the tooth consists of nanometer-sized calcium phosphate crystallites embedded in collagen fiber networks. It shows its anisotropy on the micrometer scale by its well-oriented microtubules. The detailed three-dimensional nanostructure of the hard tissues namely dentin and enamel, however, is not understood, although numerous studies on the anisotropic mechanical properties have been performed and evaluated to explain the tooth function including the enamel-dentin junction acting as effective crack barrier. Small angle X-ray scattering (SAXS) with a spatial resolution in the 10 μm range allows determining the size and orientation of the constituents on the nanometer scale with reasonable precision. So far, only some dental materials, i.e. the fiber reinforced posts exhibit anisotropic properties related to the micrometer-size glass fibers. Dental fillings, composed of nanostructures oriented similar to the natural hard tissues of teeth, however, do not exist at all. The current X-ray-based investigations of extracted human teeth provide evidence for oriented micro- and nanostructures in dentin and enamel. These fundamental quantitative findings result in profound knowledge to develop biologically inspired dental fillings with superior resistance to thermal and mechanical shocks.

Vision based speed breaker detection for autonomous vehicle

NASA Astrophysics Data System (ADS)

C. S., Arvind; Mishra, Ritesh; Vishal, Kumar; Gundimeda, Venugopal

2018-04-01

In this paper, we are presenting a robust and real-time, vision-based approach to detect speed breaker in urban environments for autonomous vehicle. Our method is designed to detect the speed breaker using visual inputs obtained from a camera mounted on top of a vehicle. The method performs inverse perspective mapping to generate top view of the road and segment out region of interest based on difference of Gaussian and median filter images. Furthermore, the algorithm performs RANSAC line fitting to identify the possible speed breaker candidate region. This initial guessed region via RANSAC, is validated using support vector machine. Our algorithm can detect different categories of speed breakers on cement, asphalt and interlock roads at various conditions and have achieved a recall of 0.98.

Bio-inspired Computing for Robots

NASA Technical Reports Server (NTRS)

Laufenberg, Larry

2003-01-01

Living creatures may provide algorithms to enable active sensing/control systems in robots. Active sensing could enable planetary rovers to feel their way in unknown environments. The surface of Jupiter's moon Europa consists of fractured ice over a liquid sea that may contain microbes similar to those on Earth. To explore such extreme environments, NASA needs robots that autonomously survive, navigate, and gather scientific data. They will be too far away for guidance from Earth. They must sense their environment and control their own movements to avoid obstacles or investigate a science opportunity. To meet this challenge, CICT's Information Technology Strategic Research (ITSR) Project is funding neurobiologists at NASA's Jet Propulsion Laboratory (JPL) and selected universities to search for biologically inspired algorithms that enable robust active sensing and control for exploratory robots. Sources for these algorithms are living creatures, including rats and electric fish.

Bio-inspired nano tools for neuroscience.

PubMed

Das, Suradip; Carnicer-Lombarte, Alejandro; Fawcett, James W; Bora, Utpal

2016-07-01

Research and treatment in the nervous system is challenged by many physiological barriers posing a major hurdle for neurologists. The CNS is protected by a formidable blood brain barrier (BBB) which limits surgical, therapeutic and diagnostic interventions. The hostile environment created by reactive astrocytes in the CNS along with the limited regeneration capacity of the PNS makes functional recovery after tissue damage difficult and inefficient. Nanomaterials have the unique ability to interface with neural tissue in the nano-scale and are capable of influencing the function of a single neuron. The ability of nanoparticles to transcend the BBB through surface modifications has been exploited in various neuro-imaging techniques and for targeted drug delivery. The tunable topography of nanofibers provides accurate spatio-temporal guidance to regenerating axons. This review is an attempt to comprehend the progress in understanding the obstacles posed by the complex physiology of the nervous system and the innovations in design and fabrication of advanced nanomaterials drawing inspiration from natural phenomenon. We also discuss the development of nanomaterials for use in Neuro-diagnostics, Neuro-therapy and the fabrication of advanced nano-devices for use in opto-electronic and ultrasensitive electrophysiological applications. The energy efficient and parallel computing ability of the human brain has inspired the design of advanced nanotechnology based computational systems. However, extensive use of nanomaterials in neuroscience also raises serious toxicity issues as well as ethical concerns regarding nano implants in the brain. In conclusion we summarize these challenges and provide an insight into the huge potential of nanotechnology platforms in neuroscience. Copyright © 2016 Elsevier Ltd. All rights reserved.

Direct comparison of the performance of a bio-inspired synthetic nickel catalyst and a [NiFe]-hydrogenase, both covalently attached to electrodes.

PubMed

Rodriguez-Maciá, Patricia; Dutta, Arnab; Lubitz, Wolfgang; Shaw, Wendy J; Rüdiger, Olaf

2015-10-12

The active site of hydrogenases has been a source of inspiration for the development of molecular catalysts. However, direct comparisons between molecular catalysts and enzymes have not been possible because different techniques are used to evaluate both types of catalysts, minimizing our ability to determine how far we have come in mimicking the enzymatic performance. The catalytic properties of the [Ni(P(Cy) 2 N(Gly) 2 )2 ](2+) complex with the [NiFe]-hydrogenase from Desulfovibrio vulgaris immobilized on a functionalized electrode were compared under identical conditions. At pH 7, the enzyme shows higher activity and lower overpotential with better stability, while at low pH, the molecular catalyst outperforms the enzyme in all respects. This is the first direct comparison of enzymes and molecular complexes, enabling a unique understanding of the benefits and detriments of both systems, and advancing our understanding of the utilization of these bio-inspired complexes in fuel cells. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Biologically Inspired Technology Using Electroactive Polymers (EAP)

NASA Technical Reports Server (NTRS)

Bar-Cohen, Yoseph

2006-01-01

Evolution allowed nature to introduce highly effective biological mechanisms that are incredible inspiration for innovation. Humans have always made efforts to imitate nature's inventions and we are increasingly making advances that it becomes significantly easier to imitate, copy, and adapt biological methods, processes and systems. This brought us to the ability to create technology that is far beyond the simple mimicking of nature. Having better tools to understand and to implement nature's principles we are now equipped like never before to be inspired by nature and to employ our tools in far superior ways. Effectively, by bio-inspiration we can have a better view and value of nature capability while studying its models to learn what can be extracted, copied or adapted. Using electroactive polymers (EAP) as artificial muscles is adding an important element to the development of biologically inspired technologies.

Recent Advances in Skin-Inspired Sensors Enabled by Nanotechnology

NASA Astrophysics Data System (ADS)

Loh, Kenneth J.; Azhari, Faezeh

2012-07-01

The highly optimized performance of nature's creations and biological assemblies has inspired the development of their bio-inspired artificial counterparts that can potentially outperform conventional systems. In particular, the skin of humans, animals, and insects exhibits unique functionalities and properties and has subsequently led to active research in developing skin-inspired sensors. This paper presents a summary of selected work related to skin-inspired tactile, distributed strain, and artificial hair cell flow sensors, with a particular focus on technologies enabled by recent advancements in the nanotechnology domain. The purpose is not to present a comprehensive review on this broad subject matter but rather to use selected work to outline the diversity of current research activities.

Comparing Neuromorphic Solutions in Action: Implementing a Bio-Inspired Solution to a Benchmark Classification Task on Three Parallel-Computing Platforms

PubMed Central

Diamond, Alan; Nowotny, Thomas; Schmuker, Michael

2016-01-01

Neuromorphic computing employs models of neuronal circuits to solve computing problems. Neuromorphic hardware systems are now becoming more widely available and “neuromorphic algorithms” are being developed. As they are maturing toward deployment in general research environments, it becomes important to assess and compare them in the context of the applications they are meant to solve. This should encompass not just task performance, but also ease of implementation, speed of processing, scalability, and power efficiency. Here, we report our practical experience of implementing a bio-inspired, spiking network for multivariate classification on three different platforms: the hybrid digital/analog Spikey system, the digital spike-based SpiNNaker system, and GeNN, a meta-compiler for parallel GPU hardware. We assess performance using a standard hand-written digit classification task. We found that whilst a different implementation approach was required for each platform, classification performances remained in line. This suggests that all three implementations were able to exercise the model's ability to solve the task rather than exposing inherent platform limits, although differences emerged when capacity was approached. With respect to execution speed and power consumption, we found that for each platform a large fraction of the computing time was spent outside of the neuromorphic device, on the host machine. Time was spent in a range of combinations of preparing the model, encoding suitable input spiking data, shifting data, and decoding spike-encoded results. This is also where a large proportion of the total power was consumed, most markedly for the SpiNNaker and Spikey systems. We conclude that the simulation efficiency advantage of the assessed specialized hardware systems is easily lost in excessive host-device communication, or non-neuronal parts of the computation. These results emphasize the need to optimize the host-device communication architecture

Quadrupedal galloping control for a wide range of speed via vertical impulse scaling.

PubMed

Park, Hae-Won; Kim, Sangbae

2015-03-25

This paper presents a bio-inspired quadruped controller that allows variable-speed galloping. The controller design is inspired by observations from biological runners. Quadrupedal animals increase the vertical impulse that is generated by ground reaction forces at each stride as running speed increases and the duration of each stance phase reduces, whereas the swing phase stays relatively constant. Inspired by this observation, the presented controller estimates the required vertical impulse at each stride by applying the linear momentum conservation principle in the vertical direction and prescribes the ground reaction forces at each stride. The design process begins with deriving a planar model from the MIT Cheetah 2 robot. A baseline periodic limit cycle is obtained by optimizing ground reaction force profiles and the temporal gait pattern (timing and duration of gait phases). To stabilize the optimized limit cycle, the obtained limit cycle is converted to a state feedback controller by representing the obtained ground reaction force profiles as functions of the state variable, which is monotonically increasing throughout the gait, adding impedance control around the height and pitch trajectories of the obtained limit cycle and introducing a finite state machine and a pattern stabilizer to enforce the optimized gait pattern. The controller that achieves a stable 3 m s(-1) gallop successfully adapts the speed change by scaling the vertical ground reaction force to match the momentum lost by gravity and adding a simple speed controller that controls horizontal speed. Without requiring additional gait optimization processes, the controller achieves galloping at speeds ranging from 3 m s(-1) to 14.9 m s(-1) while respecting the torque limit of the motor used in the MIT Cheetah 2 robot. The robustness of the controller is verified by demonstrating stable running during various disturbances, including 1.49 m step down and 0.18 m step up, as well as random ground

A nonlinear mechanics model of bio-inspired hierarchical lattice materials consisting of horseshoe microstructures

PubMed Central

Ma, Qiang; Cheng, Huanyu; Jang, Kyung-In; Luan, Haiwen; Hwang, Keh-Chih; Rogers, John A.; Huang, Yonggang; Zhang, Yihui

2016-01-01

Development of advanced synthetic materials that can mimic the mechanical properties of non-mineralized soft biological materials has important implications in a wide range of technologies. Hierarchical lattice materials constructed with horseshoe microstructures belong to this class of bio-inspired synthetic materials, where the mechanical responses can be tailored to match the nonlinear J-shaped stress-strain curves of human skins. The underlying relations between the J-shaped stress-strain curves and their microstructure geometry are essential in designing such systems for targeted applications. Here, a theoretical model of this type of hierarchical lattice material is developed by combining a finite deformation constitutive relation of the building block (i.e., horseshoe microstructure), with the analyses of equilibrium and deformation compatibility in the periodical lattices. The nonlinear J-shaped stress-strain curves and Poisson ratios predicted by this model agree very well with results of finite element analyses (FEA) and experiment. Based on this model, analytic solutions were obtained for some key mechanical quantities, e.g., elastic modulus, Poisson ratio, peak modulus, and critical strain around which the tangent modulus increases rapidly. A negative Poisson effect is revealed in the hierarchical lattice with triangular topology, as opposed to a positive Poisson effect in hierarchical lattices with Kagome and honeycomb topologies. The lattice topology is also found to have a strong influence on the stress-strain curve. For the three isotropic lattice topologies (triangular, Kagome and honeycomb), the hierarchical triangular lattice material renders the sharpest transition in the stress-strain curve and relative high stretchability, given the same porosity and arc angle of horseshoe microstructure. Furthermore, a demonstrative example illustrates the utility of the developed model in the rapid optimization of hierarchical lattice materials for

A nonlinear mechanics model of bio-inspired hierarchical lattice materials consisting of horseshoe microstructures

NASA Astrophysics Data System (ADS)

Ma, Qiang; Cheng, Huanyu; Jang, Kyung-In; Luan, Haiwen; Hwang, Keh-Chih; Rogers, John A.; Huang, Yonggang; Zhang, Yihui

2016-05-01

Development of advanced synthetic materials that can mimic the mechanical properties of non-mineralized soft biological materials has important implications in a wide range of technologies. Hierarchical lattice materials constructed with horseshoe microstructures belong to this class of bio-inspired synthetic materials, where the mechanical responses can be tailored to match the nonlinear J-shaped stress-strain curves of human skins. The underlying relations between the J-shaped stress-strain curves and their microstructure geometry are essential in designing such systems for targeted applications. Here, a theoretical model of this type of hierarchical lattice material is developed by combining a finite deformation constitutive relation of the building block (i.e., horseshoe microstructure), with the analyses of equilibrium and deformation compatibility in the periodical lattices. The nonlinear J-shaped stress-strain curves and Poisson ratios predicted by this model agree very well with results of finite element analyses (FEA) and experiment. Based on this model, analytic solutions were obtained for some key mechanical quantities, e.g., elastic modulus, Poisson ratio, peak modulus, and critical strain around which the tangent modulus increases rapidly. A negative Poisson effect is revealed in the hierarchical lattice with triangular topology, as opposed to a positive Poisson effect in hierarchical lattices with Kagome and honeycomb topologies. The lattice topology is also found to have a strong influence on the stress-strain curve. For the three isotropic lattice topologies (triangular, Kagome and honeycomb), the hierarchical triangular lattice material renders the sharpest transition in the stress-strain curve and relative high stretchability, given the same porosity and arc angle of horseshoe microstructure. Furthermore, a demonstrative example illustrates the utility of the developed model in the rapid optimization of hierarchical lattice materials for

A nonlinear mechanics model of bio-inspired hierarchical lattice materials consisting of horseshoe microstructures.

PubMed

Ma, Qiang; Cheng, Huanyu; Jang, Kyung-In; Luan, Haiwen; Hwang, Keh-Chih; Rogers, John A; Huang, Yonggang; Zhang, Yihui

2016-05-01

Development of advanced synthetic materials that can mimic the mechanical properties of non-mineralized soft biological materials has important implications in a wide range of technologies. Hierarchical lattice materials constructed with horseshoe microstructures belong to this class of bio-inspired synthetic materials, where the mechanical responses can be tailored to match the nonlinear J-shaped stress-strain curves of human skins. The underlying relations between the J-shaped stress-strain curves and their microstructure geometry are essential in designing such systems for targeted applications. Here, a theoretical model of this type of hierarchical lattice material is developed by combining a finite deformation constitutive relation of the building block (i.e., horseshoe microstructure), with the analyses of equilibrium and deformation compatibility in the periodical lattices. The nonlinear J-shaped stress-strain curves and Poisson ratios predicted by this model agree very well with results of finite element analyses (FEA) and experiment. Based on this model, analytic solutions were obtained for some key mechanical quantities, e.g., elastic modulus, Poisson ratio, peak modulus, and critical strain around which the tangent modulus increases rapidly. A negative Poisson effect is revealed in the hierarchical lattice with triangular topology, as opposed to a positive Poisson effect in hierarchical lattices with Kagome and honeycomb topologies. The lattice topology is also found to have a strong influence on the stress-strain curve. For the three isotropic lattice topologies (triangular, Kagome and honeycomb), the hierarchical triangular lattice material renders the sharpest transition in the stress-strain curve and relative high stretchability, given the same porosity and arc angle of horseshoe microstructure. Furthermore, a demonstrative example illustrates the utility of the developed model in the rapid optimization of hierarchical lattice materials for

NegBio: a high-performance tool for negation and uncertainty detection in radiology reports.

PubMed

Peng, Yifan; Wang, Xiaosong; Lu, Le; Bagheri, Mohammadhadi; Summers, Ronald; Lu, Zhiyong

2018-01-01

Negative and uncertain medical findings are frequent in radiology reports, but discriminating them from positive findings remains challenging for information extraction. Here, we propose a new algorithm, NegBio, to detect negative and uncertain findings in radiology reports. Unlike previous rule-based methods, NegBio utilizes patterns on universal dependencies to identify the scope of triggers that are indicative of negation or uncertainty. We evaluated NegBio on four datasets, including two public benchmarking corpora of radiology reports, a new radiology corpus that we annotated for this work, and a public corpus of general clinical texts. Evaluation on these datasets demonstrates that NegBio is highly accurate for detecting negative and uncertain findings and compares favorably to a widely-used state-of-the-art system NegEx (an average of 9.5% improvement in precision and 5.1% in F1-score). https://github.com/ncbi-nlp/NegBio.

New bioactive bone-like microspheres with intrinsic magnetic properties obtained by bio-inspired mineralisation process.

PubMed

Fernandes Patrício, Tatiana Marisa; Panseri, Silvia; Sandri, Monica; Tampieri, Anna; Sprio, Simone

2017-08-01

A bio-inspired mineralisation process was investigated and applied to develop novel hybrid magnetic materials by heterogeneous nucleation of Fe 2+ /Fe 3+ -doped hydroxyapatite nanocrystals onto a biopolymeric matrix made of a Type I collagen-based recombinant peptide (RCP). The effect of the synthesis temperature on the phase composition, crystallinity and magnetic properties of the nucleated inorganic phase was studied. The as-obtained magnetic materials were then engineered, by using a water-in-oil emulsification process, into hybrid magnetic microspheres, which were stabilized by de-hydrothermal treatment yielding cross-linking of the macromolecular matrix. Thorough investigation of the physicochemical, morphological and biological properties of the new hybrid microspheres, as induced by the presence of the inorganic nanophase and controlled iron substitution into hydroxyapatite lattice, revealed bone-like composition, good cytocompatibility, designed shape and size, and tailored magnetization. Such features are interesting and promising for application as new biomaterials with ability of remote activation and control by using external magnetic fields, for smart and personalized applications in medicine, particularly in bone tissue regeneration. Copyright © 2017 Elsevier B.V. All rights reserved.

A noble metal-free proton-exchange membrane fuel cell based on bio-inspired molecular catalysts.

PubMed

Tran, P D; Morozan, A; Archambault, S; Heidkamp, J; Chenevier, P; Dau, H; Fontecave, M; Martinent, A; Jousselme, B; Artero, V

2015-03-01

Hydrogen is a promising energy vector for storing renewable energies: obtained from water-splitting, in electrolysers or photoelectrochemical cells, it can be turned back to electricity on demand in fuel cells (FCs). Proton exchange membrane (PEM) devices with low internal resistance, high compactness and stability are an attractive technology optimized over decades, affording fast start-up times and low operating temperatures. However, they rely on the powerful catalytic properties of noble metals such as platinum, while lower cost, more abundant materials would be needed for economic viability. Replacing these noble metals at both electrodes has long proven to be a difficult task, so far incompatible with PEM technologies. Here we take advantage of newly developed bio-inspired molecular H 2 oxidation catalysts and noble metal-free O 2 -reducing materials, to fabricate a noble metal-free PEMFC, with an 0.74 V open circuit voltage and a 23 μW cm -2 output power under technologically relevant conditions. X-ray absorption spectroscopy measurements confirm that the catalysts are stable and retain their structure during turnover.

A wireless fatigue monitoring system utilizing a bio-inspired tree ring data tracking technique.

PubMed

Bai, Shi; Li, Xuan; Xie, Zhaohui; Zhou, Zhi; Ou, Jinping

2014-03-05

Fatigue, a hot scientific research topic for centuries, can trigger sudden failure of critical structures such as aircraft and railway systems, resulting in enormous casualties as well as economic losses. The fatigue life of certain structures is intrinsically random and few monitoring techniques are capable of tracking the full life-cycle fatigue damage. In this paper, a novel in-situ wireless real-time fatigue monitoring system using a bio-inspired tree ring data tracking technique is proposed. The general framework, methodology, and verification of this intelligent system are discussed in details. The rain-flow counting (RFC) method is adopted as the core algorithm which quantifies fatigue damages, and Digital Signal Processing (DSP) is introduced as the core module for data collection and analysis. Laboratory test results based on strain gauges and polyvinylidene fluoride (PVDF) sensors have shown that the developed intelligent system can provide a reliable quick feedback and early warning of fatigue failure. With the merits of low cost, high accuracy and great reliability, the developed wireless fatigue sensing system can be further applied to mechanical engineering, civil infrastructures, transportation systems, aerospace engineering, etc.

A Wireless Fatigue Monitoring System Utilizing a Bio-Inspired Tree Ring Data Tracking Technique

PubMed Central

Bai, Shi; Li, Xuan; Xie, Zhaohui; Zhou, Zhi; Ou, Jinping

2014-01-01

Fatigue, a hot scientific research topic for centuries, can trigger sudden failure of critical structures such as aircraft and railway systems, resulting in enormous casualties as well as economic losses. The fatigue life of certain structures is intrinsically random and few monitoring techniques are capable of tracking the full life-cycle fatigue damage. In this paper, a novel in-situ wireless real-time fatigue monitoring system using a bio-inspired tree ring data tracking technique is proposed. The general framework, methodology, and verification of this intelligent system are discussed in details. The rain-flow counting (RFC) method is adopted as the core algorithm which quantifies fatigue damages, and Digital Signal Processing (DSP) is introduced as the core module for data collection and analysis. Laboratory test results based on strain gauges and polyvinylidene fluoride (PVDF) sensors have shown that the developed intelligent system can provide a reliable quick feedback and early warning of fatigue failure. With the merits of low cost, high accuracy and great reliability, the developed wireless fatigue sensing system can be further applied to mechanical engineering, civil infrastructures, transportation systems, aerospace engineering, etc. PMID:24603635

Parameter estimation with bio-inspired meta-heuristic optimization: modeling the dynamics of endocytosis.

PubMed

Tashkova, Katerina; Korošec, Peter; Silc, Jurij; Todorovski, Ljupčo; Džeroski, Sašo

2011-10-11

artificial data, for all observability scenarios considered, and for all amounts of noise added to the artificial data. In sum, the meta-heuristic methods considered are suitable for estimating the parameters in the ODE model of the dynamics of endocytosis under a range of conditions: With the model and conditions being representative of parameter estimation tasks in ODE models of biochemical systems, our results clearly highlight the promise of bio-inspired meta-heuristic methods for parameter estimation in dynamic system models within system biology.

Parameter estimation with bio-inspired meta-heuristic optimization: modeling the dynamics of endocytosis

PubMed Central

2011-01-01

results hold for both real and artificial data, for all observability scenarios considered, and for all amounts of noise added to the artificial data. In sum, the meta-heuristic methods considered are suitable for estimating the parameters in the ODE model of the dynamics of endocytosis under a range of conditions: With the model and conditions being representative of parameter estimation tasks in ODE models of biochemical systems, our results clearly highlight the promise of bio-inspired meta-heuristic methods for parameter estimation in dynamic system models within system biology. PMID:21989196

Bio-inspired magnetic swimming microrobots for biomedical applications.

PubMed

Peyer, Kathrin E; Zhang, Li; Nelson, Bradley J

2013-02-21

Microrobots have been proposed for future biomedical applications in which they are able to navigate in viscous fluidic environments. Nature has inspired numerous microrobotic locomotion designs, which are suitable for propulsion generation at low Reynolds numbers. This article reviews the various swimming methods with particular focus on helical propulsion inspired by E. coli bacteria. There are various magnetic actuation methods for biomimetic and non-biomimetic microrobots, such as rotating fields, oscillating fields, or field gradients. They can be categorized into force-driven or torque-driven actuation methods. Both approaches are reviewed and a previous publication has shown that torque-driven actuation scales better to the micro- and nano-scale than force-driven actuation. Finally, the implementation of swarm or multi-agent control is discussed. The use of multiple microrobots may be beneficial for in vivo as well as in vitro applications. Thus, the frequency-dependent behavior of helical microrobots is discussed and preliminary experimental results are presented showing the decoupling of an individual agent within a group of three microrobots.

High-speed event detector for embedded nanopore bio-systems.

PubMed

Huang, Yiyun; Magierowski, Sebastian; Ghafar-Zadeh, Ebrahim; Wang, Chengjie

2015-08-01

Biological measurements of microscopic phenomena often deal with discrete-event signals. The ability to automatically carry out such measurements at high-speed in a miniature embedded system is desirable but compromised by high-frequency noise along with practical constraints on filter quality and sampler resolution. This paper presents a real-time event-detection method in the context of nanopore sensing that helps to mitigate these drawbacks and allows accurate signal processing in an embedded system. Simulations show at least a 10× improvement over existing on-line detection methods.

Communication analysis for feedback control of civil infrastructure using cochlea-inspired sensing nodes

NASA Astrophysics Data System (ADS)

Peckens, Courtney A.; Cook, Ireana; Lynch, Jerome P.

2016-04-01

Wireless sensor networks (WSNs) have emerged as a reliable, low-cost alternative to the traditional wired sensing paradigm. While such networks have made significant progress in the field of structural monitoring, significantly less development has occurred for feedback control applications. Previous work in WSNs for feedback control has highlighted many of the challenges of using this technology including latency in the wireless communication channel and computational inundation at the individual sensing nodes. This work seeks to overcome some of those challenges by drawing inspiration from the real-time sensing and control techniques employed by the biological central nervous system and in particular the mammalian cochlea. A novel bio-inspired wireless sensor node was developed that employs analog filtering techniques to perform time-frequency decomposition of a sensor signal, thus encompassing the functionality of the cochlea. The node then utilizes asynchronous sampling of the filtered signal to compress the signal prior to communication. This bio-inspired sensing architecture is extended to a feedback control application in order to overcome the traditional challenges currently faced by wireless control. In doing this, however, the network experiences high bandwidths of low-significance information exchange between nodes, resulting in some lost data. This study considers the impact of this lost data on the control capabilities of the bio-inspired control architecture and finds that it does not significantly impact the effectiveness of control.

Bio-inspired hybrid microelectrodes: a hybrid solution to improve long-term performance of chronic intracortical implants.

PubMed

De Faveri, Sara; Maggiolini, Emma; Miele, Ermanno; De Angelis, Francesco; Cesca, Fabrizia; Benfenati, Fabio; Fadiga, Luciano

2014-01-01

The use of implants that allow chronic electrical stimulation and recording in the brain of human patients is currently limited by a series of events that cause the deterioration over time of both the electrode surface and the surrounding tissue. The main reason of failure is the tissue inflammatory reaction that eventually causes neuronal loss and glial encapsulation, resulting in a progressive increase of the electrode-electrolyte impedance. Here, we describe a new method to create bio-inspired electrodes to mimic the mechanical properties and biological composition of the host tissue. This combination has a great potential to increase the implant lifetime by reducing tissue reaction and improving electrical coupling. Our method implies coating the electrode with reprogrammed neural or glial cells encapsulated within a hydrogel layer. We chose fibrin as a hydrogel and primary hippocampal neurons or astrocytes from rat brain as cellular layer. We demonstrate that fibrin coating is highly biocompatible, forms uniform coatings of controllable thickness, does not alter the electrochemical properties of the microelectrode and allows good quality recordings. Moreover, it reduces the amount of host reactive astrocytes - over time - compared to a bare wire and is fully reabsorbed by the surrounding tissue within 7 days after implantation, avoiding the common problem of hydrogels swelling. Both astrocytes and neurons could be successfully grown onto the electrode surface within the fibrin hydrogel without altering the electrochemical properties of the microelectrode. This bio-hybrid device has therefore a good potential to improve the electrical integration at the neuron-electrode interface and support the long-term success of neural prostheses.

Nanoplatforms for Detection, Remediation and Protection Against Chem-Bio Warfare

NASA Astrophysics Data System (ADS)

Denkbaş, E. B.; Bayram, C.; Kavaz, D.; Çirak, T.; Demirbilek, M.

Chemical and biological substances have been used as warfare agents by terrorists by varying degree of sophistication. It is critical that these agents be detected in real-time with high level of sensitively, specificity, and accuracy. Many different types of techniques and systems have been developed to detect these agents. But there are some limitations in these conventional techniques and systems. Limitations include the collection, handling and sampling procedures, detection limits, sample transfer, expensive equipment, personnel training, and detection materials. Due to the unique properties such as quantum effect, very high surface/volume ratio, enhanced surface reactivity, conductivity, electrical and magnetic properties of the nanomaterials offer great opportunity to develop very fast, sensitive, accurate and cost effective detection techniques and systems to detect chemical and biological (chem.-bio) warfare agents. Furthermore, surface modification of the materials is very easy and effective way to get functional or smart surfaces to be used as nano-biosensor platform. In that respect many different types of nanomaterials have been developed and used for the detection, remediation and protection, such as gold and silver nanoparticles, quantum dots, Nano chips and arrays, fluorescent polymeric and magnetic nanoparticles, fiber optic and cantilever based nanobiosensors, nanofibrillar nanostructures etc. This study summarizes preparation and characterization of nanotechnology based approaches for the detection of and remediation and protection against chem.-bio warfare agents.

Wave study of compound eyes for efficient infrared detection

NASA Astrophysics Data System (ADS)

Kilinc, Takiyettin Oytun; Hayran, Zeki; Kocer, Hasan; Kurt, Hamza

2017-08-01

Improving sensitivity in the infrared spectrum is a challenging task. Detecting infrared light over a wide bandwidth and at low power consumption is very important. Novel solutions can be acquired by mimicking biological eyes such as compound eye with many individual lenses inspired from the nature. The nature provides many ingenious approaches of sensing and detecting the surrounding environment. Even though compound eye consists of small optical units, it can detect wide-angle electromagnetic waves and it has high transmission and low reflection loss. Insects have eyes that are superior compared to human eyes (single-aperture eyes) in terms of compactness, robustness, wider field of view, higher sensitivity of light intensity and being cheap vision systems. All these desired properties are accompanied by an important drawback: lower spatial resolution. The first step to investigate the feasibility of bio-inspired optics in photodetectors is to perform light interaction with the optical system that gather light and detect it. The most common method used in natural vision systems is the ray analysis. Light wave characteristics are not taken into consideration in such analyses, such as the amount of energy at the focal point or photoreceptor site, the losses caused by reflection at the interfaces and absorption cannot be investigated. In this study, we present a bio-inspired optical detection system investigated by wave analysis. We numerically model the wave analysis based on Maxwell equations from the viewpoint of efficient light detection and revealing the light propagation after intercepting the first interface of the eye towards the photoreceptor site.

A comparative study of bio-inspired protective scales using 3D printing and mechanical testing.

PubMed

Martini, Roberto; Balit, Yanis; Barthelat, Francois

2017-06-01

Flexible natural armors from fish, alligators or armadillo are attracting an increasing amount of attention for their unique combinations of hardness, flexibility and light weight. The extreme contrast of stiffness between hard scales and surrounding soft tissues gives rise to unusual and attractive mechanisms, which now serve as models for the design of bio-inspired armors. Despite this growing interest, there is little guideline for the choice of materials, optimum thickness, size, shape and arrangement for the protective scales. In this work, we explore how the geometry and arrangement of hard scales can be tailored to promote scale-scale interactions. We use 3D printing to fabricate arrays of scales with increasingly complex geometries and arrangements, from simple squares with no overlap to complex ganoid-scales with overlaps and interlocking features. We performed puncture tests and flexural tests on each of the 3D printed materials, and we report the puncture resistance - compliance characteristics of each design on an Ashby chart. The interactions between the scales can significantly increase the resistance to puncture, and these interactions can be maximized by tuning the geometry and arrangement of the scales. Interestingly, the designs that offer the best combinations of puncture resistance and flexural compliance are similar to the geometry and arrangement of natural teleost and ganoid scales, which suggests that natural evolution has shaped these systems to maximize flexible protection. This study yields new insights into the mechanisms of natural dermal armor, and also suggests new designs for personal protective systems. Flexible natural armors from fishes, alligators or armadillos are attracting an increasing amount of attention for their unique and attractive combinations of hardness, flexibility and low weight. Despite a growing interest in bio-inspired flexible protection, there is still little guideline for the choice of materials, optimum

Self-organization, embodiment, and biologically inspired robotics.

PubMed

Pfeifer, Rolf; Lungarella, Max; Iida, Fumiya

2007-11-16

Robotics researchers increasingly agree that ideas from biology and self-organization can strongly benefit the design of autonomous robots. Biological organisms have evolved to perform and survive in a world characterized by rapid changes, high uncertainty, indefinite richness, and limited availability of information. Industrial robots, in contrast, operate in highly controlled environments with no or very little uncertainty. Although many challenges remain, concepts from biologically inspired (bio-inspired) robotics will eventually enable researchers to engineer machines for the real world that possess at least some of the desirable properties of biological organisms, such as adaptivity, robustness, versatility, and agility.

Network Community Detection based on the Physarum-inspired Computational Framework.

PubMed

Gao, Chao; Liang, Mingxin; Li, Xianghua; Zhang, Zili; Wang, Zhen; Zhou, Zhili

2016-12-13

Community detection is a crucial and essential problem in the structure analytics of complex networks, which can help us understand and predict the characteristics and functions of complex networks. Many methods, ranging from the optimization-based algorithms to the heuristic-based algorithms, have been proposed for solving such a problem. Due to the inherent complexity of identifying network structure, how to design an effective algorithm with a higher accuracy and a lower computational cost still remains an open problem. Inspired by the computational capability and positive feedback mechanism in the wake of foraging process of Physarum, which is a large amoeba-like cell consisting of a dendritic network of tube-like pseudopodia, a general Physarum-based computational framework for community detection is proposed in this paper. Based on the proposed framework, the inter-community edges can be identified from the intra-community edges in a network and the positive feedback of solving process in an algorithm can be further enhanced, which are used to improve the efficiency of original optimization-based and heuristic-based community detection algorithms, respectively. Some typical algorithms (e.g., genetic algorithm, ant colony optimization algorithm, and Markov clustering algorithm) and real-world datasets have been used to estimate the efficiency of our proposed computational framework. Experiments show that the algorithms optimized by Physarum-inspired computational framework perform better than the original ones, in terms of accuracy and computational cost. Moreover, a computational complexity analysis verifies the scalability of our framework.

Detection of airborne bacteria with disposable bio-precipitator and NanoGene assay.

PubMed

Lee, Eun-Hee; Chua, Beelee; Son, Ahjeong

2016-09-15

We demonstrated the detection of airborne bacteria by a disposable bio-precipitator and NanoGene assay combination. The bio-precipitator employed micro corona discharge at 1960V and at less than 35µA to simultaneously charge, capture and lyse the airborne bacteria. This was enabled by the use of a 15μL liquid anode. Using a custom exposure setup, the target bacterium Bacillus subtilis in the atomization solution was rendered airborne. After exposure, the liquid anode in the bio-precipitator was subsequently measured for DNA concentration and analyzed with the NanoGene assay. As the bacterial concentration increased from 0.0104 to 42.6 g-DCW/L the released DNA concentration in the liquid anode increased from 2.10±1.57 to 75.00±7.15ng/μL. More importantly, the NanoGene assay showed an increase in normalized fluorescence (gene quantification) from 18.03±1.18 to 49.71±1.82 as the bacterial concentrations increased from 0.0104 to 42.6 g-DCW/L. the electrical power consumption of the bio-precipitator was shown to be amenable for portable use. In addition, the detection limit of bio-precipitator and NanoGene assay combination in the context of environmentally relevant levels of airborne bacteria was also discussed. Copyright © 2016 Elsevier B.V. All rights reserved.

One-Pot Evolution of Ageladine A through a Bio-Inspired Cascade towards Selective Modulators of Neuronal Differentiation.

PubMed

Iwata, Takayuki; Otsuka, Satoshi; Tsubokura, Kazuki; Kurbangalieva, Almira; Arai, Daisuke; Fukase, Koichi; Nakao, Yoichi; Tanaka, Katsunori

2016-10-04

A bio-inspired cascade reaction has been developed for the construction of the marine natural product ageladine A and a de novo array of its N1-substituted derivatives. This cascade features a 2-aminoimidazole formation that is modeled after an arginine post-translational modification and an aza-electrocyclization. It can be effectively carried out in a one-pot procedure from simple anilines or guanidines, leading to structural analogues of ageladine A that had been otherwise synthetically inaccessible. We found that some compounds out of this structurally novel library show a significant activity in modulating the neural differentiation. Namely, these compounds selectively activate or inhibit the differentiation of neural stem cells to neurons, while being negligible in the differentiation to astrocytes. This study represents a successful case in which the native biofunction of a natural product could be altered by structural modifications. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A Bio-Inspired Model-Based Approach for Context-Aware Post-WIMP Tele-Rehabilitation.

PubMed

López-Jaquero, Víctor; Rodríguez, Arturo C; Teruel, Miguel A; Montero, Francisco; Navarro, Elena; Gonzalez, Pascual

2016-10-13

Tele-rehabilitation is one of the main domains where Information and Communication Technologies (ICT) have been proven useful to move healthcare from care centers to patients' home. Moreover, patients, especially those carrying out a physical therapy, cannot use a traditional Window, Icon, Menu, Pointer (WIMP) system, but they need to interact in a natural way, that is, there is a need to move from WIMP systems to Post-WIMP ones. Moreover, tele-rehabilitation systems should be developed following the context-aware approach, so that they are able to adapt to the patients' context to provide them with usable and effective therapies. In this work a model-based approach is presented to assist stakeholders in the development of context-aware Post-WIMP tele-rehabilitation systems. It entails three different models: (i) a task model for designing the rehabilitation tasks; (ii) a context model to facilitate the adaptation of these tasks to the context; and (iii) a bio-inspired presentation model to specify thoroughly how such tasks should be performed by the patients. Our proposal overcomes one of the limitations of the model-based approach for the development of context-aware systems supporting the specification of non-functional requirements. Finally, a case study is used to illustrate how this proposal can be put into practice to design a real world rehabilitation task.

Incipient Fault Detection for Rolling Element Bearings under Varying Speed Conditions.

PubMed

Xue, Lang; Li, Naipeng; Lei, Yaguo; Li, Ningbo

2017-06-20

Varying speed conditions bring a huge challenge to incipient fault detection of rolling element bearings because both the change of speed and faults could lead to the amplitude fluctuation of vibration signals. Effective detection methods need to be developed to eliminate the influence of speed variation. This paper proposes an incipient fault detection method for bearings under varying speed conditions. Firstly, relative residual (RR) features are extracted, which are insensitive to the varying speed conditions and are able to reflect the degradation trend of bearings. Then, a health indicator named selected negative log-likelihood probability (SNLLP) is constructed to fuse a feature set including RR features and non-dimensional features. Finally, based on the constructed SNLLP health indicator, a novel alarm trigger mechanism is designed to detect the incipient fault. The proposed method is demonstrated using vibration signals from bearing tests and industrial wind turbines. The results verify the effectiveness of the proposed method for incipient fault detection of rolling element bearings under varying speed conditions.

Carbon-Nanotube-Supported Bio-Inspired Nickel Catalyst and Its Integration in Hybrid Hydrogen/Air Fuel Cells.

PubMed

Gentil, Solène; Lalaoui, Noémie; Dutta, Arnab; Nedellec, Yannig; Cosnier, Serge; Shaw, Wendy J; Artero, Vincent; Le Goff, Alan

2017-02-06

A biomimetic nickel bis-diphosphine complex incorporating the amino acid arginine in the outer coordination sphere was immobilized on modified carbon nanotubes (CNTs) through electrostatic interactions. The functionalized redox nanomaterial exhibits reversible electrocatalytic activity for the H 2 /2 H + interconversion from pH 0 to 9, with catalytic preference for H 2 oxidation at all pH values. The high activity of the complex over a wide pH range allows us to integrate this bio-inspired nanomaterial either in an enzymatic fuel cell together with a multicopper oxidase at the cathode, or in a proton exchange membrane fuel cell (PEMFC) using Pt/C at the cathode. The Ni-based PEMFC reaches 14 mW cm -2 , only six-times-less as compared to full-Pt conventional PEMFC. The Pt-free enzyme-based fuel cell delivers ≈2 mW cm -2 , a new efficiency record for a hydrogen biofuel cell with base metal catalysts. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Tidal interactions of inspiraling compact binaries

NASA Technical Reports Server (NTRS)

Bildsten, Lars; Cutler, Curt

1992-01-01

We discuss the tidal interaction in neutron star-neutron star and neutron star-black hole binaries and argue that they will not be tidally locked during the gravitational inspiral. More specifically, we show that, for inspiraling neutron stars of mass greater than about 1.2 solar mass, the shortest possible tidal synchronization time exceeds the gravitational decay time, so that the neutron star cannot be tidally locked prior to tidal disruption, regardless of its internal viscosity. For smaller mass neutron stars, an implausibly large kinematic viscosity - nearly the speed of light times the stellar radius - is required for tidal locking. We also argue that the mass transfer which occurs when the neutron star reaches the tidal radius will be unstable in neutron star-black hole binaries, and the instability will destroy the neutron star in a few orbital periods. The implications of our work for the detection of these sources by LIGO and other gravitational wave observatories and for the gamma-ray burst scenarios of Paczynski (1986, 1991) are discussed.

Boundary layer drag reduction research hypotheses derived from bio-inspired surface and recent advanced applications.

PubMed

Luo, Yuehao; Yuan, Lu; Li, Jianhua; Wang, Jianshe

2015-12-01

Nature has supplied the inexhaustible resources for mankind, and at the same time, it has also progressively developed into the school for scientists and engineers. Through more than four billions years of rigorous and stringent evolution, different creatures in nature gradually exhibit their own special and fascinating biological functional surfaces. For example, sharkskin has the potential drag-reducing effect in turbulence, lotus leaf possesses the self-cleaning and anti-foiling function, gecko feet have the controllable super-adhesion surfaces, the flexible skin of dolphin can accelerate its swimming velocity. Great profits of applying biological functional surfaces in daily life, industry, transportation and agriculture have been achieved so far, and much attention from all over the world has been attracted and focused on this field. In this overview, the bio-inspired drag-reducing mechanism derived from sharkskin is explained and explored comprehensively from different aspects, and then the main applications in different fluid engineering are demonstrated in brief. This overview will inevitably improve the comprehension of the drag reduction mechanism of sharkskin surface and better understand the recent applications in fluid engineering. Copyright © 2015 Elsevier Ltd. All rights reserved.

Bio-inspired hybrid microelectrodes: a hybrid solution to improve long-term performance of chronic intracortical implants

PubMed Central

De Faveri, Sara; Maggiolini, Emma; Miele, Ermanno; De Angelis, Francesco; Cesca, Fabrizia; Benfenati, Fabio; Fadiga, Luciano

2014-01-01

The use of implants that allow chronic electrical stimulation and recording in the brain of human patients is currently limited by a series of events that cause the deterioration over time of both the electrode surface and the surrounding tissue. The main reason of failure is the tissue inflammatory reaction that eventually causes neuronal loss and glial encapsulation, resulting in a progressive increase of the electrode-electrolyte impedance. Here, we describe a new method to create bio-inspired electrodes to mimic the mechanical properties and biological composition of the host tissue. This combination has a great potential to increase the implant lifetime by reducing tissue reaction and improving electrical coupling. Our method implies coating the electrode with reprogrammed neural or glial cells encapsulated within a hydrogel layer. We chose fibrin as a hydrogel and primary hippocampal neurons or astrocytes from rat brain as cellular layer. We demonstrate that fibrin coating is highly biocompatible, forms uniform coatings of controllable thickness, does not alter the electrochemical properties of the microelectrode and allows good quality recordings. Moreover, it reduces the amount of host reactive astrocytes – over time – compared to a bare wire and is fully reabsorbed by the surrounding tissue within 7 days after implantation, avoiding the common problem of hydrogels swelling. Both astrocytes and neurons could be successfully grown onto the electrode surface within the fibrin hydrogel without altering the electrochemical properties of the microelectrode. This bio-hybrid device has therefore a good potential to improve the electrical integration at the neuron-electrode interface and support the long-term success of neural prostheses. PMID:24782757

Incipient Fault Detection for Rolling Element Bearings under Varying Speed Conditions

PubMed Central

Xue, Lang; Li, Naipeng; Lei, Yaguo; Li, Ningbo

2017-01-01

Varying speed conditions bring a huge challenge to incipient fault detection of rolling element bearings because both the change of speed and faults could lead to the amplitude fluctuation of vibration signals. Effective detection methods need to be developed to eliminate the influence of speed variation. This paper proposes an incipient fault detection method for bearings under varying speed conditions. Firstly, relative residual (RR) features are extracted, which are insensitive to the varying speed conditions and are able to reflect the degradation trend of bearings. Then, a health indicator named selected negative log-likelihood probability (SNLLP) is constructed to fuse a feature set including RR features and non-dimensional features. Finally, based on the constructed SNLLP health indicator, a novel alarm trigger mechanism is designed to detect the incipient fault. The proposed method is demonstrated using vibration signals from bearing tests and industrial wind turbines. The results verify the effectiveness of the proposed method for incipient fault detection of rolling element bearings under varying speed conditions. PMID:28773035

Production of bioelectricity, bio-hydrogen, high value chemicals and bioinspired nanomaterials by electrochemically active biofilms.

PubMed

Kalathil, Shafeer; Khan, Mohammad Mansoob; Lee, Jintae; Cho, Moo Hwan

2013-11-01

Microorganisms naturally form biofilms on solid surfaces for their mutual benefits including protection from environmental stresses caused by contaminants, nutritional depletion or imbalances. The biofilms are normally dangerous to human health due to their inherited robustness. On the other hand, a recent study suggested that electrochemically active biofilms (EABs) generated by electrically active microorganisms have properties that can be used to catalyze or control the electrochemical reactions in a range of fields, such as bioenergy production, bioremediation, chemical/biological synthesis, bio-corrosion mitigation and biosensor development. EABs have attracted considerable attraction in bioelectrochemical systems (BESs), such as microbial fuel cells and microbial electrolysis cells, where they act as living bioanode or biocathode catalysts. Recently, it was reported that EABs can be used to synthesize metal nanoparticles and metal nanocomposites. The EAB-mediated synthesis of metal and metal-semiconductor nanocomposites is expected to provide a new avenue for the greener synthesis of nanomaterials with high efficiency and speed than other synthetic methods. This review covers the general introduction of EABs, as well as the applications of EABs in BESs, and the production of bio-hydrogen, high value chemicals and bio-inspired nanomaterials. Copyright © 2013 Elsevier Inc. All rights reserved.

Detection strategies for extreme mass ratio inspirals

NASA Astrophysics Data System (ADS)

Cornish, Neil J.

2011-05-01

The capture of compact stellar remnants by galactic black holes provides a unique laboratory for exploring the near-horizon geometry of the Kerr spacetime, or possible departures from general relativity if the central cores prove not to be black holes. The gravitational radiation produced by these extreme mass ratio inspirals (EMRIs) encodes a detailed map of the black hole geometry, and the detection and characterization of these signals is a major scientific goal for the LISA mission. The waveforms produced are very complex, and the signals need to be coherently tracked for tens of thousands of cycles to produce a detection, making EMRI signals one of the most challenging data analysis problems in all of gravitational wave astronomy. Estimates for the number of templates required to perform an exhaustive grid-based matched-filter search for these signals are astronomically large, and far out of reach of current computational resources. Here I describe an alternative approach that employs a hybrid between genetic algorithms and Markov chain Monte Carlo techniques, along with several time-saving techniques for computing the likelihood function. This approach has proven effective at the blind extraction of relatively weak EMRI signals from simulated LISA data sets.

Bio-inspired co-catalysts bonded to a silicon photocathode for solar hydrogen evolution

NASA Astrophysics Data System (ADS)

Hou, Yidong; Abrams, Billie L.; Vesborg, Peter C. K.; Bjørketun, Mårten E.; Herbst, Konrad; Bech, Lone; Seger, Brian; Pedersen, Thomas; Hansen, Ole; Rossmeisl, Jan; Dahl, Søren; Nørskov, Jens K.; Chorkendorff, Ib

2011-10-01

The production of fuels directly or indirectly from sunlight represents one of the major challenges to the development of a sustainable energy system. Hydrogen is the simplest fuel to produce and while platinum and other noble metals are efficient catalysts for photoelectrochemical hydrogen evolution, earth-abundant alternatives are needed for largescale use. We show that bio-inspired molecular clusters based on molybdenum sulfides and tungsten sulfides mimic nature's enzymes for hydrogen evolution, molybdenum sulfides evolve hydrogen at a slightly higher overpotential than platinum when deposited on various supports. It will be demonstrated how this overpotential can be eliminated by depositing the same type of hydrogen evolution catalyst on p-type Si which can harvest the red part of the solar spectrum. Such a system could constitute the cathode part of a tandem dream device where the red part of the spectrum is utilized for hydrogen evolution while the blue part is reserved for the more difficult oxygen evolution. The samples have been illuminated with a simulated red part of the solar spectrum i.e. long wavelength (" > 620 nm) part of simulated AM 1.5G radiation. The current densities at the reversible potential match the requirement of a photoelectrochemical hydrogen production system with a solar-to-hydrogen efficiency in excess of 10%. The experimental observations are supported by DFT calculations of the Mo3S4 cluster adsorbed on the hydrogen-terminated silicon surface providing insights into the nature of the active site.

Experimental study of surface pattern effects on the propulsive performance and wake of a bio-inspired pitching panel

NASA Astrophysics Data System (ADS)

King, Justin; Kumar, Rajeev; Green, Melissa

2016-11-01

Force measurements and stereoscopic particle image velocimetry (PIV) were used to characterize the propulsive performance and wake structure of rigid, bio-inspired trapezoidal pitching panels. In the literature, it has been demonstrated that quantities such as thrust coefficient and propulsive efficiency are affected by changes in the surface characteristics of a pitching panel or foil. More specifically, the variation of surface pattern produces significant changes in wake structure and dynamics, especially in the distribution of vorticity in the wake. Force measurements and PIV data were collected for multiple surface patterns chosen to mimic fish surface morphology over a Strouhal number range of 0.17 to 0.56. Performance quantities are compared with the three-dimensional vortex wake structure for both the patterned and smooth panels to determine the nature and magnitude of surface pattern effects in terms of thrust produced, drag reduced, and wake vortices reshaped and reorganized. This work was supported by the Office of Naval Research under ONR Award No. N00014-14-1-0418.

Detection of HIV-1 p24 Gag in plasma by a nanoparticle-based bio-barcode-amplification method.

PubMed

Kim, Eun-Young; Stanton, Jennifer; Korber, Bette T M; Krebs, Kendall; Bogdan, Derek; Kunstman, Kevin; Wu, Samuel; Phair, John P; Mirkin, Chad A; Wolinsky, Steven M

2008-06-01

Detection of HIV-1 in patients is limited by the sensitivity and selectivity of available tests. The nanotechnology-based bio-barcode-amplification method offers an innovative approach to detect specific HIV-1 antigens from diverse HIV-1 subtypes. We evaluated the efficacy of this protein-detection method in detecting HIV-1 in men enrolled in the Chicago component of the Multicenter AIDS Cohort Study (MACS). The method relies on magnetic microparticles with antibodies that specifically bind the HIV-1 p24 Gag protein and nanoparticles that are encoded with DNA and antibodies that can sandwich the target protein captured by the microparticle-bound antibodies. The aggregate sandwich structures are magnetically separated from solution, and treated to remove the conjugated barcode DNA. The DNA barcodes (hundreds per target) were identified by a nanoparticle-based detection method that does not rely on PCR. Of 112 plasma samples from HIV-1-infected subjects, 111 were positive for HIV-1 p24 Gag protein (range: 0.11-71.5 ng/ml of plasma) by the bio-barcode-amplification method. HIV-1 p24 Gag protein was detected in only 23 out of 112 men by the conventional ELISA. A total of 34 uninfected subjects were negative by both tests. Thus, the specificity of the bio-barcode-amplification method was 100% and the sensitivity 99%. The bio-barcode-amplification method detected HIV-1 p24 Gag protein in plasma from all study subjects with less than 200 CD4(+) T cells/microl of plasma (100%) and 19 out of 20 (95%) HIV-1-infected men who had less than 50 copies/ml of plasma of HIV-1 RNA. In a separate group of 60 diverse international isolates, representative of clades A, B, C and D and circulating recombinant forms CRF01_AE and CRF02_AG, the bio-barcode-amplification method identified the presence of virus correctly. The bio-barcode-amplification method was superior to the conventional ELISA assay for the detection of HIV-1 p24 Gag protein in plasma with a breadth of coverage for diverse

DSP-Based dual-polarity mass spectrum pattern recognition for bio-detection

DOE Office of Scientific and Technical Information (OSTI.GOV)

Riot, V; Coffee, K; Gard, E

2006-04-21

The Bio-Aerosol Mass Spectrometry (BAMS) instrument analyzes single aerosol particles using a dual-polarity time-of-flight mass spectrometer recording simultaneously spectra of thirty to a hundred thousand points on each polarity. We describe here a real-time pattern recognition algorithm developed at Lawrence Livermore National Laboratory that has been implemented on a nine Digital Signal Processor (DSP) system from Signatec Incorporated. The algorithm first preprocesses independently the raw time-of-flight data through an adaptive baseline removal routine. The next step consists of a polarity dependent calibration to a mass-to-charge representation, reducing the data to about five hundred to a thousand channels per polarity. Themore » last step is the identification step using a pattern recognition algorithm based on a library of known particle signatures including threat agents and background particles. The identification step includes integrating the two polarities for a final identification determination using a score-based rule tree. This algorithm, operating on multiple channels per-polarity and multiple polarities, is well suited for parallel real-time processing. It has been implemented on the PMP8A from Signatec Incorporated, which is a computer based board that can interface directly to the two one-Giga-Sample digitizers (PDA1000 from Signatec Incorporated) used to record the two polarities of time-of-flight data. By using optimized data separation, pipelining, and parallel processing across the nine DSPs it is possible to achieve a processing speed of up to a thousand particles per seconds, while maintaining the recognition rate observed on a non-real time implementation. This embedded system has allowed the BAMS technology to improve its throughput and therefore its sensitivity while maintaining a large dynamic range (number of channels and two polarities) thus maintaining the systems specificity for bio-detection.« less

Pushing the lipid envelope: using bio-inspired nanocomposites to understand and exploit lipid membrane limitations

NASA Astrophysics Data System (ADS)

Montano, Gabriel

Lipids serve as the organizing matrix material for biological membranes, the site of interaction of cells with the external environment. . As such, lipids play a critical role in structure/function relationships of an extraordinary number of critical biological processes. In this talk, we will look at bio-inspired membrane assemblies to better understand the roles of lipids in biological systems as well as attempt to generate materials that can mimic and potentially advance upon biological membrane processes. First, we will investigate the response of lipids to adverse conditions. In particular, I will present data that demonstrates the response of lipids to harsh conditions and how such responses can be exploited to generate nanocomposite rearrangements. I will also show the effect of adding the endotoxin lipopolysaccharide (LPS) to lipid bilayer assemblies and describe implications on our understanding of LPS organization in biological systems as well as describe induced lipid modifications that can be exploited to organize membrane composites with precise, two-dimensional geometric control. Lastly, I will describe the use of amphiphilic block copolymers to create membrane nanocomposites capable of mimicking biological systems. In particular, I will describe the use of our polymer-based membranes in creating artificial photosynthetic assemblies that rival biological systems in function in a more flexible, dynamic matrix.

Fabrication, testing and modeling of a new flexible armor inspired from natural fish scales and osteoderms.

PubMed

Chintapalli, Ravi Kiran; Mirkhalaf, Mohammad; Dastjerdi, Ahmad Khayer; Barthelat, Francois

2014-09-01

Crocodiles, armadillo, turtles, fish and many other animal species have evolved flexible armored skins in the form of hard scales or osteoderms, which can be described as hard plates of finite size embedded in softer tissues. The individual hard segments provide protection from predators, while the relative motion of these segments provides the flexibility required for efficient locomotion. In this work, we duplicated these broad concepts in a bio-inspired segmented armor. Hexagonal segments of well-defined size and shape were carved within a thin glass plate using laser engraving. The engraved plate was then placed on a soft substrate which simulated soft tissues, and then punctured with a sharp needle mounted on a miniature loading stage. The resistance of our segmented armor was significantly higher when smaller hexagons were used, and our bio-inspired segmented glass displayed an increase in puncture resistance of up to 70% compared to a continuous plate of glass of the same thickness. Detailed structural analyses aided by finite elements revealed that this extraordinary improvement is due to the reduced span of individual segments, which decreases flexural stresses and delays fracture. This effect can however only be achieved if the plates are at least 1000 stiffer than the underlying substrate, which is the case for natural armor systems. Our bio-inspired system also displayed many of the attributes of natural armors: flexible, robust with 'multi-hit' capabilities. This new segmented glass therefore suggests interesting bio-inspired strategies and mechanisms which could be systematically exploited in high-performance flexible armors. This study also provides new insights and a better understanding of the mechanics of natural armors such as scales and osteoderms.

A review on robotic fish enabled by ionic polymer-metal composite artificial muscles.

PubMed

Chen, Zheng

2017-01-01

A novel actuating material, which is lightweight, soft, and capable of generating large flapping motion under electrical stimuli, is highly desirable to build energy-efficient and maneuverable bio-inspired underwater robots. Ionic polymer-metal composites are important category of electroactive polymers, since they can generate large bending motions under low actuation voltages. IPMCs are ideal artificial muscles for small-scale and bio-inspired robots. This paper takes a system perspective to review the recent work on IPMC-enabled underwater robots, from modeling, fabrication, and bio-inspired design perspectives. First, a physics-based and control-oriented model of IPMC actuator will be reviewed. Second, a bio-inspired robotic fish propelled by IPMC caudal fin will be presented and a steady-state speed model of the fish will be demonstrated. Third, a novel fabrication process for 3D actuating membrane will be introduced and a bio-inspired robotic manta ray propelled by two IPMC pectoral fins will be demonstrated. Fourth, a 2D maneuverable robotic fish propelled by multiple IPMC fin will be presented. Last, advantages and challenges of using IPMC artificial muscles in bio-inspired robots will be concluded.

Bio-inspired hemispherical compound eye camera

NASA Astrophysics Data System (ADS)

Xiao, Jianliang; Song, Young Min; Xie, Yizhu; Malyarchuk, Viktor; Jung, Inhwa; Choi, Ki-Joong; Liu, Zhuangjian; Park, Hyunsung; Lu, Chaofeng; Kim, Rak-Hwan; Li, Rui; Crozier, Kenneth B.; Huang, Yonggang; Rogers, John A.

2014-03-01

Compound eyes in arthropods demonstrate distinct imaging characteristics from human eyes, with wide angle field of view, low aberrations, high acuity to motion and infinite depth of field. Artificial imaging systems with similar geometries and properties are of great interest for many applications. However, the challenges in building such systems with hemispherical, compound apposition layouts cannot be met through established planar sensor technologies and conventional optics. We present our recent progress in combining optics, materials, mechanics and integration schemes to build fully functional artificial compound eye cameras. Nearly full hemispherical shapes (about 160 degrees) with densely packed artificial ommatidia were realized. The number of ommatidia (180) is comparable to those of the eyes of fire ants and bark beetles. The devices combine elastomeric compound optical elements with deformable arrays of thin silicon photodetectors, which were fabricated in the planar geometries and then integrated and elastically transformed to hemispherical shapes. Imaging results and quantitative ray-tracing-based simulations illustrate key features of operation. These general strategies seem to be applicable to other compound eye devices, such as those inspired by moths and lacewings (refracting superposition eyes), lobster and shrimp (reflecting superposition eyes), and houseflies (neural superposition eyes).

Low-cost synchronization of high-speed audio and video recordings in bio-acoustic experiments.

PubMed

Laurijssen, Dennis; Verreycken, Erik; Geipel, Inga; Daems, Walter; Peremans, Herbert; Steckel, Jan

2018-02-27

In this paper, we present a method for synchronizing high-speed audio and video recordings of bio-acoustic experiments. By embedding a random signal into the recorded video and audio data, robust synchronization of a diverse set of sensor streams can be performed without the need to keep detailed records. The synchronization can be performed using recording devices without dedicated synchronization inputs. We demonstrate the efficacy of the approach in two sets of experiments: behavioral experiments on different species of echolocating bats and the recordings of field crickets. We present the general operating principle of the synchronization method, discuss its synchronization strength and provide insights into how to construct such a device using off-the-shelf components. © 2018. Published by The Company of Biologists Ltd.

Bio-inspired self-healing structural color hydrogel

PubMed Central

Fu, Fanfan; Chen, Zhuoyue; Zhao, Ze; Wang, Huan; Shang, Luoran; Gu, Zhongze

2017-01-01

Biologically inspired self-healing structural color hydrogels were developed by adding a glucose oxidase (GOX)- and catalase (CAT)-filled glutaraldehyde cross-linked BSA hydrogel into methacrylated gelatin (GelMA) inverse opal scaffolds. The composite hydrogel materials with the polymerized GelMA scaffold could maintain the stability of an inverse opal structure and its resultant structural colors, whereas the protein hydrogel filler could impart self-healing capability through the reversible covalent attachment of glutaraldehyde to lysine residues of BSA and enzyme additives. A series of unprecedented structural color materials could be created by assembling and healing the elements of the composite hydrogel. In addition, as both the GelMA and the protein hydrogels were derived from organisms, the composite materials presented high biocompatibility and plasticity. These features of self-healing structural color hydrogels make them excellent functional materials for different applications. PMID:28533368

Retina-Inspired Filter.

PubMed

Doutsi, Effrosyni; Fillatre, Lionel; Antonini, Marc; Gaulmin, Julien

2018-07-01

This paper introduces a novel filter, which is inspired by the human retina. The human retina consists of three different layers: the Outer Plexiform Layer (OPL), the inner plexiform layer, and the ganglionic layer. Our inspiration is the linear transform which takes place in the OPL and has been mathematically described by the neuroscientific model "virtual retina." This model is the cornerstone to derive the non-separable spatio-temporal OPL retina-inspired filter, briefly renamed retina-inspired filter, studied in this paper. This filter is connected to the dynamic behavior of the retina, which enables the retina to increase the sharpness of the visual stimulus during filtering before its transmission to the brain. We establish that this retina-inspired transform forms a group of spatio-temporal Weighted Difference of Gaussian (WDoG) filters when it is applied to a still image visible for a given time. We analyze the spatial frequency bandwidth of the retina-inspired filter with respect to time. It is shown that the WDoG spectrum varies from a lowpass filter to a bandpass filter. Therefore, while time increases, the retina-inspired filter enables to extract different kinds of information from the input image. Finally, we discuss the benefits of using the retina-inspired filter in image processing applications such as edge detection and compression.

Augmented kludge waveforms for detecting extreme-mass-ratio inspirals

NASA Astrophysics Data System (ADS)

Chua, Alvin J. K.; Moore, Christopher J.; Gair, Jonathan R.

2017-08-01

The extreme-mass-ratio inspirals (EMRIs) of stellar-mass compact objects into massive black holes are an important class of source for the future space-based gravitational-wave detector LISA. Detecting signals from EMRIs will require waveform models that are both accurate and computationally efficient. In this paper, we present the latest implementation of an augmented analytic kludge (AAK) model, publicly available at https://github.com/alvincjk/EMRI_Kludge_Suite as part of an EMRI waveform software suite. This version of the AAK model has improved accuracy compared to its predecessors, with two-month waveform overlaps against a more accurate fiducial model exceeding 0.97 for a generic range of sources; it also generates waveforms 5-15 times faster than the fiducial model. The AAK model is well suited for scoping out data analysis issues in the upcoming round of mock LISA data challenges. A simple analytic argument shows that it might even be viable for detecting EMRIs with LISA through a semicoherent template bank method, while the use of the original analytic kludge in the same approach will result in around 90% fewer detections.

Invited Review Article: Review of centrifugal microfluidic and bio-optical disks

PubMed Central

Nolte, David D.

2009-01-01

Spinning biodisks have advantages that make them attractive for specialized biochip applications. The two main classes of spinning biodisks are microfluidic disks and bio-optical compact disks (BioCD). Microfluidic biodisks take advantage of noninertial pumping for lab-on-a-chip devices using noninertial valves and switches under centrifugal and Coriolis forces to distribute fluids about the disks. BioCDs use spinning-disk interferometry, under the condition of common-path phase quadrature, to perform interferometric label-free detection of molecular recognition and binding. The optical detection of bound molecules on a disk is facilitated by rapid spinning that enables high-speed repetitive sampling to eliminate 1∕f noise through common-mode rejection of intensity fluctuations and extensive signal averaging. Multiple quadrature classes have been developed, such as microdiffraction, in-line, phase contrast, and holographic adaptive optics. Thin molecular films are detected through the surface dipole density with a surface height sensitivity for the detection of protein spots that is approximately 1 pm. This sensitivity easily resolves a submonolayer of solid-support immobilized antibodies and their antigen targets. Fluorescence and light scattering provide additional optical detection techniques on spinning disks. Immunoassays have been applied to haptoglobin using protein A∕G immobilization of antibodies and to prostate specific antigen. Small protein spots enable scalability to many spots per disk for high-throughput and highly multiplexed immonoassays. PMID:19895047

An IPMC-enabled bio-inspired bending/twisting fin for underwater applications

NASA Astrophysics Data System (ADS)

Palmre, Viljar; Hubbard, Joel J.; Fleming, Maxwell; Pugal, David; Kim, Sungjun; Kim, Kwang J.; Leang, Kam K.

2013-01-01

This paper discusses the design, fabrication, and characterization of an ionic polymer-metal composite (IPMC) actuator-based bio-inspired active fin capable of bending and twisting motion. It is pointed out that IPMC strip actuators are used in the simple cantilever configuration to create simple bending (flapping-like) motion for propulsion in underwater autonomous systems. However, the resulting motion is a simple 1D bending and performance is rather limited. To enable more complex deformation, such as the flapping (pitch and heaving) motion of real pectoral and caudal fish fins, a new approach which involves molding or integrating IPMC actuators into a soft boot material to create an active control surface (called a ‘fin’) is presented. The fin can be used to realize complex deformation depending on the orientation and placement of the actuators. In contrast to previously created IPMCs with patterned electrodes for the same purpose, the proposed design avoids (1) the more expensive process of electroless plating platinum all throughout the surface of the actuator and (2) the need for specially patterning the electrodes. Therefore, standard shaped IPMC actuators such as those with rectangular dimensions with varying thicknesses can be used. One unique advantage of the proposed structural design is that custom shaped fins and control surfaces can be easily created without special materials processing. The molding process is cost effective and does not require functionalizing or ‘activating’ the boot material similar to creating IPMCs. For a prototype fin (90 mm wide × 60 mm long × 1.5 mm thick), the measured maximum tip displacement was approximately 44 mm and the twist angle of the fin exceeded 10°. Lift and drag measurements in water where the prototype fin with an airfoil profile was dragged through water at a velocity of 21 cm s-1 showed that the lift and drag forces can be affected by controlling the IPMCs embedded into the fin structure. These

Dew inspired breathing-based detection of genetic point mutation visualized by naked eye

PubMed Central

Xie, Liping; Wang, Tongzhou; Huang, Tianqi; Hou, Wei; Huang, Guoliang; Du, Yanan

2014-01-01

A novel label-free method based on breathing-induced vapor condensation was developed for detection of genetic point mutation. The dew-inspired detection was realized by integration of target-induced DNA ligation with rolling circle amplification (RCA). The vapor condensation induced by breathing transduced the RCA-amplified variances in DNA contents into visible contrast. The image could be recorded by a cell phone for further or even remote analysis. This green assay offers a naked-eye-reading method potentially applied for point-of-care liver cancer diagnosis in resource-limited regions. PMID:25199907

Dew inspired breathing-based detection of genetic point mutation visualized by naked eye

NASA Astrophysics Data System (ADS)

Xie, Liping; Wang, Tongzhou; Huang, Tianqi; Hou, Wei; Huang, Guoliang; Du, Yanan

2014-09-01

A novel label-free method based on breathing-induced vapor condensation was developed for detection of genetic point mutation. The dew-inspired detection was realized by integration of target-induced DNA ligation with rolling circle amplification (RCA). The vapor condensation induced by breathing transduced the RCA-amplified variances in DNA contents into visible contrast. The image could be recorded by a cell phone for further or even remote analysis. This green assay offers a naked-eye-reading method potentially applied for point-of-care liver cancer diagnosis in resource-limited regions.

Dew inspired breathing-based detection of genetic point mutation visualized by naked eye.

PubMed

Xie, Liping; Wang, Tongzhou; Huang, Tianqi; Hou, Wei; Huang, Guoliang; Du, Yanan

2014-09-09

A novel label-free method based on breathing-induced vapor condensation was developed for detection of genetic point mutation. The dew-inspired detection was realized by integration of target-induced DNA ligation with rolling circle amplification (RCA). The vapor condensation induced by breathing transduced the RCA-amplified variances in DNA contents into visible contrast. The image could be recorded by a cell phone for further or even remote analysis. This green assay offers a naked-eye-reading method potentially applied for point-of-care liver cancer diagnosis in resource-limited regions.

Enhancing thermal reliability of fiber-optic sensors for bio-inspired applications at ultra-high temperatures

NASA Astrophysics Data System (ADS)

Kang, Donghoon; Kim, Heon-Young; Kim, Dae-Hyun

2014-07-01

The rapid growth of bio-(inspired) sensors has led to an improvement in modern healthcare and human-robot systems in recent years. Higher levels of reliability and better flexibility, essential features of these sensors, are very much required in many application fields (e.g. applications at ultra-high temperatures). Fiber-optic sensors, and fiber Bragg grating (FBG) sensors in particular, are being widely studied as suitable sensors for improved structural health monitoring (SHM) due to their many merits. To enhance the thermal reliability of FBG sensors, thermal sensitivity, generally expressed as αf + ξf and considered a constant, should be investigated more precisely. For this purpose, the governing equation of FBG sensors is modified using differential derivatives between the wavelength shift and the temperature change in this study. Through a thermal test ranging from RT to 900 °C, the thermal sensitivity of FBG sensors is successfully examined and this guarantees thermal reliability of FBG sensors at ultra-high temperatures. In detail, αf + ξf has a non-linear dependence on temperature and varies from 6.0 × 10-6 °C-1 (20 °C) to 10.6 × 10-6 °C-1 (650 °C). Also, FBGs should be carefully used for applications at ultra-high temperatures due to signal disappearance near 900 °C.

Bio-inspired Plasmonic Nanoarchitectured Hybrid System Towards Enhanced Far Red-to-Near Infrared Solar Photocatalysis

NASA Astrophysics Data System (ADS)

Yan, Runyu; Chen, Min; Zhou, Han; Liu, Tian; Tang, Xingwei; Zhang, Ke; Zhu, Hanxing; Ye, Jinhua; Zhang, Di; Fan, Tongxiang

2016-01-01

Solar conversion to fuels or to electricity in semiconductors using far red-to-near infrared (NIR) light, which accounts for about 40% of solar energy, is highly significant. One main challenge is the development of novel strategies for activity promotion and new basic mechanisms for NIR response. Mother Nature has evolved to smartly capture far red-to-NIR light via their intelligent systems due to unique micro/nanoarchitectures, thus motivating us for biomimetic design. Here we report the first demonstration of a new strategy, based on adopting nature’s far red-to-NIR responsive architectures for an efficient bio-inspired photocatalytic system. The system is constructed by controlled assembly of light-harvesting plasmonic nanoantennas onto a typical photocatalytic unit with butterfly wings’ 3D micro/nanoarchitectures. Experiments and finite-difference time-domain (FDTD) simulations demonstrate the structural effects on obvious far red-to-NIR photocatalysis enhancement, which originates from (1) Enhancing far red-to-NIR (700~1200 nm) harvesting, up to 25%. (2) Enhancing electric-field amplitude of localized surface plasmon (LSPs) to more than 3.5 times than that of the non-structured one, which promotes the rate of electron-hole pair formation, thus substantially reinforcing photocatalysis. This proof-of-concept study provides a new methodology for NIR photocatalysis and would potentially guide future conceptually new NIR responsive system designs.

Bio-inspired Plasmonic Nanoarchitectured Hybrid System Towards Enhanced Far Red-to-Near Infrared Solar Photocatalysis.

PubMed

Yan, Runyu; Chen, Min; Zhou, Han; Liu, Tian; Tang, Xingwei; Zhang, Ke; Zhu, Hanxing; Ye, Jinhua; Zhang, Di; Fan, Tongxiang

2016-01-28

Solar conversion to fuels or to electricity in semiconductors using far red-to-near infrared (NIR) light, which accounts for about 40% of solar energy, is highly significant. One main challenge is the development of novel strategies for activity promotion and new basic mechanisms for NIR response. Mother Nature has evolved to smartly capture far red-to-NIR light via their intelligent systems due to unique micro/nanoarchitectures, thus motivating us for biomimetic design. Here we report the first demonstration of a new strategy, based on adopting nature's far red-to-NIR responsive architectures for an efficient bio-inspired photocatalytic system. The system is constructed by controlled assembly of light-harvesting plasmonic nanoantennas onto a typical photocatalytic unit with butterfly wings' 3D micro/nanoarchitectures. Experiments and finite-difference time-domain (FDTD) simulations demonstrate the structural effects on obvious far red-to-NIR photocatalysis enhancement, which originates from (1) Enhancing far red-to-NIR (700~1200 nm) harvesting, up to 25%. (2) Enhancing electric-field amplitude of localized surface plasmon (LSPs) to more than 3.5 times than that of the non-structured one, which promotes the rate of electron-hole pair formation, thus substantially reinforcing photocatalysis. This proof-of-concept study provides a new methodology for NIR photocatalysis and would potentially guide future conceptually new NIR responsive system designs.

Characterization of anthocyanin based dye-sensitized organic solar cells (DSSC) and modifications based on bio-inspired ion mobility improvements

NASA Astrophysics Data System (ADS)

Mawyin, Jose Amador

The worldwide electrical energy consumption will increase from currently 10 terawatts to 30 terawatts by 2050. To decrease the current atmospheric CO2 would require our civilization to develop a 20 terawatts non-greenhouse emitting (renewable) electrical power generation capability. Solar photovoltaic electric power generation is thought to be a major component of proposed renewable energy-based economy. One approach to less costly, easily manufactured solar cells is the Dye-sensitized solar cells (DSSC) introduced by Greatzel and others. This dissertation describes the work focused on improving the performance of DSSC type solar cells. In particular parameters affecting dye-sensitized solar cells (DSSC) based on anthocyanin pigments extracted from California blackberries (Rubus ursinus) and bio-inspired modifications were analyzed and solar cell designs optimized. Using off-the-shelf materials DSSC were constructed and tested using a custom made solar spectrum simulator and photoelectric property characterization. This equipment facilitated the taking of automated I-V curve plots and the experimental determination of parameters such as open circuit voltage (V OC), short circuit current (JSC), fill factor (FF), etc. This equipment was used to probe the effect of various modifications such as changes in the annealing time and composition of the of the electrode counter-electrode. Solar cell optimization schemes included novel schemes such as solar spectrum manipulation to increase the percentage of the solar spectrum capable of generating power in the DSSC. Solar manipulation included light scattering and photon upconversion. Techniques examined here focused on affordable materials such as silica nanoparticles embedded inside a TiO2 matrix. Such materials were examined for controlled scattering of visible light and optimize light trapping within the matrix as well as a means to achieve photon up-energy-conversion using the Raman effect in silica nano-particles (due

Bio-inspired robot design for viscous fluids

NASA Astrophysics Data System (ADS)

Ma, Grace; Lipman, Tyler; Jung, Sunghwan

Many modern micro-robots are designed for biomedical applications to transport drugs to targets or to operate tests in the body for diagnosis. However, most micro-robots simply mimic the morphology and the propulsive mechanism of micro-organisms without understanding the underlying physics of low-Re swimming. Two types of swimming motions have been observed in micro-organisms; stresslet and source-dipole swimming. The stresslet swimmer (e.g. E. coli) uses a rotating helical appendage, whereas the source-dipole swimmer (e.g. Paramecium) creates surface velocity for propulsion. Using this principle, we designed a robot to swim in very viscous fluids either by rotating a helix or creating surface velocity, simply by changing the orientation of the appendage. Further, we will discuss the performance of this robot (swimming speed and rotation speed) with respect to the number, winding angle, and radius of helices in a very viscous fluid.

Controlled biological and biomimetic systems for landmine detection.

PubMed

Habib, Maki K

2007-08-30

Humanitarian demining requires to accurately detect, locate and deactivate every single landmine and other buried mine-like objects as safely and as quickly as possible, and in the most non-invasive manner. The quality of landmine detection affects directly the efficiency and safety of this process. Most of the available methods to detect explosives and landmines are limited by their sensitivity and/or operational complexities. All landmines leak with time small amounts of their explosives that can be found on surrounding ground and plant life. Hence, explosive signatures represent the robust primary indicator of landmines. Accordingly, developing innovative technologies and efficient techniques to identify in real-time explosives residue in mined areas represents an attractive and promising approach. Biological and biologically inspired detection technology has the potential to compete with or be used in conjunction with other artificial technology to complement performance strengths. Biological systems are sensitive to many different scents concurrently, a property that has proven difficult to replicate artificially. Understanding biological systems presents unique opportunities for developing new capabilities through direct use of trained bio-systems, integration of living and non-living components, or inspiring new design by mimicking biological capabilities. It is expected that controlled bio-systems, biotechnology and microbial techniques will contribute to the advancement of mine detection and other application domains. This paper provides directions, evaluation and analysis on the progress of controlled biological and biomimetic systems for landmine detection. It introduces and discusses different approaches developed, underlining their relative advantages and limitations, and highlighting trends, safety and ecology concern, and possible future directions.

Vehicle speed detection based on gaussian mixture model using sequential of images

NASA Astrophysics Data System (ADS)

Setiyono, Budi; Ratna Sulistyaningrum, Dwi; Soetrisno; Fajriyah, Farah; Wahyu Wicaksono, Danang

2017-09-01

Intelligent Transportation System is one of the important components in the development of smart cities. Detection of vehicle speed on the highway is supporting the management of traffic engineering. The purpose of this study is to detect the speed of the moving vehicles using digital image processing. Our approach is as follows: The inputs are a sequence of frames, frame rate (fps) and ROI. The steps are following: First we separate foreground and background using Gaussian Mixture Model (GMM) in each frames. Then in each frame, we calculate the location of object and its centroid. Next we determine the speed by computing the movement of centroid in sequence of frames. In the calculation of speed, we only consider frames when the centroid is inside the predefined region of interest (ROI). Finally we transform the pixel displacement into a time unit of km/hour. Validation of the system is done by comparing the speed calculated manually and obtained by the system. The results of software testing can detect the speed of vehicles with the highest accuracy is 97.52% and the lowest accuracy is 77.41%. And the detection results of testing by using real video footage on the road is included with real speed of the vehicle.

[Research on Detection Method with Wearable Respiration Device Based on the Theory of Bio-impedance].

PubMed

Liu, Guangda; Wang, Xianzhong; Cai, Jing; Wang, Wei; Zha, Yutong

2016-12-01

Considering the importance of the human respiratory signal detection and based on the Cole-Cole bio-impedance model,we developed a wearable device for detecting human respiratory signal.The device can be used to analyze the impedance characteristics of human body at different frequencies based on the bio-impedance theory.The device is also based on the method of proportion measurement to design a high signal to noise ratio(SNR)circuit to get human respiratory signal.In order to obtain the waveform of the respiratory signal and the value of the respiration rate,we used the techniques of discrete Fourier transform(DFT)and dynamic difference threshold peak detection.Experiments showed that this system was valid,and we could see that it could accurately detect the waveform of respiration and the detection accuracy rate of respiratory wave peak point detection results was over 98%.So it can meet the needs of the actual breath test.

On-line high-speed rail defect detection : part II.

DOT National Transportation Integrated Search

2012-03-01

The objectives of this project were (1) to improve the defect detection reliability and (2) to improve the inspection speed of conventional rail defect detection methods. The prototype developed in this work uses noncontact transducers, ultrasonic gu...

Electronic and optoelectronic materials and devices inspired by nature

NASA Astrophysics Data System (ADS)

Meredith, P.; Bettinger, C. J.; Irimia-Vladu, M.; Mostert, A. B.; Schwenn, P. E.

2013-03-01

Inorganic semiconductors permeate virtually every sphere of modern human existence. Micro-fabricated memory elements, processors, sensors, circuit elements, lasers, displays, detectors, etc are ubiquitous. However, the dawn of the 21st century has brought with it immense new challenges, and indeed opportunities—some of which require a paradigm shift in the way we think about resource use and disposal, which in turn directly impacts our ongoing relationship with inorganic semiconductors such as silicon and gallium arsenide. Furthermore, advances in fields such as nano-medicine and bioelectronics, and the impending revolution of the ‘ubiquitous sensor network’, all require new functional materials which are bio-compatible, cheap, have minimal embedded manufacturing energy plus extremely low power consumption, and are mechanically robust and flexible for integration with tissues, building structures, fabrics and all manner of hosts. In this short review article we summarize current progress in creating materials with such properties. We focus primarily on organic and bio-organic electronic and optoelectronic systems derived from or inspired by nature, and outline the complex charge transport and photo-physics which control their behaviour. We also introduce the concept of electrical devices based upon ion or proton flow (‘ionics and protonics’) and focus particularly on their role as a signal interface with biological systems. Finally, we highlight recent advances in creating working devices, some of which have bio-inspired architectures, and summarize the current issues, challenges and potential solutions. This is a rich new playground for the modern materials physicist.

Insect-Inspired Optical-Flow Navigation Sensors

NASA Technical Reports Server (NTRS)

Thakoor, Sarita; Morookian, John M.; Chahl, Javan; Soccol, Dean; Hines, Butler; Zornetzer, Steven

2005-01-01

Integrated circuits that exploit optical flow to sense motions of computer mice on or near surfaces ( optical mouse chips ) are used as navigation sensors in a class of small flying robots now undergoing development for potential use in such applications as exploration, search, and surveillance. The basic principles of these robots were described briefly in Insect-Inspired Flight Control for Small Flying Robots (NPO-30545), NASA Tech Briefs, Vol. 29, No. 1 (January 2005), page 61. To recapitulate from the cited prior article: The concept of optical flow can be defined, loosely, as the use of texture in images as a source of motion cues. The flight-control and navigation systems of these robots are inspired largely by the designs and functions of the vision systems and brains of insects, which have been demonstrated to utilize optical flow (as detected by their eyes and brains) resulting from their own motions in the environment. Optical flow has been shown to be very effective as a means of avoiding obstacles and controlling speeds and altitudes in robotic navigation. Prior systems used in experiments on navigating by means of optical flow have involved the use of panoramic optics, high-resolution image sensors, and programmable imagedata- processing computers.

Biomechanical model of batoid (skates and rays) pectoral fins predicts the influence of skeletal structure on fin kinematics: implications for bio-inspired design.

PubMed

Russo, R S; Blemker, S S; Fish, F E; Bart-Smith, H

2015-06-16

Growing interest in the development of bio-inspired autonomous underwater vehicles (AUVs) has motivated research in understanding the mechanisms behind the propulsion systems of marine animals. For example, the locomotive behavior of rays (Batoidea) by movement of the pectoral fins is of particular interest due to their superior performance characteristics over contemporary AUV propulsion systems. To better understand the mechanics of pectoral fin propulsion, this paper introduces a biomechanical model that simulates how batoid skeletal structures function to achieve the swimming locomotion observed in nature. Two rays were studied, Dasyatis sabina (Atlantic ray), and Rhinoptera bonasus (cownose ray). These species were selected because they exhibit very different swimming styles (undulation versus oscillation), but all use primarily their pectoral fins for propulsion (unlike electric rays or guitarfishes). Computerized tomography scans of each species were taken to image the underlying structure, which reveal a complex system of cartilaginous joints and linkages. Data collected from these images were used to quantify the complete skeletal morphometry of each batoid fin. Morphological differences were identified in the internal cartilage arrangement between each species including variations in the orientation of the skeletal elements, or radials, and the joint patterns between them, called the inter-radial joint pattern. These data were used as the primary input into the biomechanical model to couple a given ray skeletal structure with various swimming motions. A key output of the model is an estimation of the uniaxial strain that develops in the skeletal connective tissue in order for the structure to achieve motions observed during swimming. Tensile load tests of this connective tissue were conducted to further investigate the implications of the material strain predictions. The model also demonstrates that changes in the skeletal architecture (e.g., joint

A Bio-inspired Collision Avoidance Model Based on Spatial Information Derived from Motion Detectors Leads to Common Routes

PubMed Central

Bertrand, Olivier J. N.; Lindemann, Jens P.; Egelhaaf, Martin

2015-01-01

Avoiding collisions is one of the most basic needs of any mobile agent, both biological and technical, when searching around or aiming toward a goal. We propose a model of collision avoidance inspired by behavioral experiments on insects and by properties of optic flow on a spherical eye experienced during translation, and test the interaction of this model with goal-driven behavior. Insects, such as flies and bees, actively separate the rotational and translational optic flow components via behavior, i.e. by employing a saccadic strategy of flight and gaze control. Optic flow experienced during translation, i.e. during intersaccadic phases, contains information on the depth-structure of the environment, but this information is entangled with that on self-motion. Here, we propose a simple model to extract the depth structure from translational optic flow by using local properties of a spherical eye. On this basis, a motion direction of the agent is computed that ensures collision avoidance. Flying insects are thought to measure optic flow by correlation-type elementary motion detectors. Their responses depend, in addition to velocity, on the texture and contrast of objects and, thus, do not measure the velocity of objects veridically. Therefore, we initially used geometrically determined optic flow as input to a collision avoidance algorithm to show that depth information inferred from optic flow is sufficient to account for collision avoidance under closed-loop conditions. Then, the collision avoidance algorithm was tested with bio-inspired correlation-type elementary motion detectors in its input. Even then, the algorithm led successfully to collision avoidance and, in addition, replicated the characteristics of collision avoidance behavior of insects. Finally, the collision avoidance algorithm was combined with a goal direction and tested in cluttered environments. The simulated agent then showed goal-directed behavior reminiscent of components of the navigation

On-chip electrical detection of parallel loop-mediated isothermal amplification with DG-BioFETs for the detection of foodborne bacterial pathogens

USDA-ARS?s Scientific Manuscript database

The use of field effect transistors (FETs) as the transduction element for the detection of DNA amplification reactions will enable portable and inexpensive nucleic acid analysis. Transistors used as biological sensors,or BioFETs, minimize the cost and size of detection platforms by leveraging fabri...

Aerodynamic Performance and Particle Image Velocimetery of Piezo Actuated Biomimetic Manduca Sexta Engineered Wings Towards the Design and Application of a Flapping Wing Flight Vehicle

DTIC Science & Technology

2013-12-01

95 3.3. Displacement sensor ... Bio vs. engineered wing modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92 3.1. High speed camera specifications...expanding and evolving mission areas, especially in the arena of bio -inspired Flap- ping Wing Micro Air Vehicles (FWMAV). This chapter will introduce the

Underwater sonar image detection: A combination of non-local spatial information and quantum-inspired shuffled frog leaping algorithm.

PubMed

Wang, Xingmei; Liu, Shu; Liu, Zhipeng

2017-01-01

This paper proposes a combination of non-local spatial information and quantum-inspired shuffled frog leaping algorithm to detect underwater objects in sonar images. Specifically, for the first time, the problem of inappropriate filtering degree parameter which commonly occurs in non-local spatial information and seriously affects the denoising performance in sonar images, was solved with the method utilizing a novel filtering degree parameter. Then, a quantum-inspired shuffled frog leaping algorithm based on new search mechanism (QSFLA-NSM) is proposed to precisely and quickly detect sonar images. Each frog individual is directly encoded by real numbers, which can greatly simplify the evolution process of the quantum-inspired shuffled frog leaping algorithm (QSFLA). Meanwhile, a fitness function combining intra-class difference with inter-class difference is adopted to evaluate frog positions more accurately. On this basis, recurring to an analysis of the quantum-behaved particle swarm optimization (QPSO) and the shuffled frog leaping algorithm (SFLA), a new search mechanism is developed to improve the searching ability and detection accuracy. At the same time, the time complexity is further reduced. Finally, the results of comparative experiments using the original sonar images, the UCI data sets and the benchmark functions demonstrate the effectiveness and adaptability of the proposed method.

Underwater sonar image detection: A combination of non-local spatial information and quantum-inspired shuffled frog leaping algorithm

PubMed Central

Liu, Zhipeng

2017-01-01

This paper proposes a combination of non-local spatial information and quantum-inspired shuffled frog leaping algorithm to detect underwater objects in sonar images. Specifically, for the first time, the problem of inappropriate filtering degree parameter which commonly occurs in non-local spatial information and seriously affects the denoising performance in sonar images, was solved with the method utilizing a novel filtering degree parameter. Then, a quantum-inspired shuffled frog leaping algorithm based on new search mechanism (QSFLA-NSM) is proposed to precisely and quickly detect sonar images. Each frog individual is directly encoded by real numbers, which can greatly simplify the evolution process of the quantum-inspired shuffled frog leaping algorithm (QSFLA). Meanwhile, a fitness function combining intra-class difference with inter-class difference is adopted to evaluate frog positions more accurately. On this basis, recurring to an analysis of the quantum-behaved particle swarm optimization (QPSO) and the shuffled frog leaping algorithm (SFLA), a new search mechanism is developed to improve the searching ability and detection accuracy. At the same time, the time complexity is further reduced. Finally, the results of comparative experiments using the original sonar images, the UCI data sets and the benchmark functions demonstrate the effectiveness and adaptability of the proposed method. PMID:28542266

Sensing parasites: Proteomic and advanced bio-detection alternatives.

PubMed

Sánchez-Ovejero, Carlos; Benito-Lopez, Fernando; Díez, Paula; Casulli, Adriano; Siles-Lucas, Mar; Fuentes, Manuel; Manzano-Román, Raúl

2016-03-16

Parasitic diseases have a great impact in human and animal health. The gold standard for the diagnosis of the majority of parasitic infections is still conventional microscopy, which presents important limitations in terms of sensitivity and specificity and commonly requires highly trained technicians. More accurate molecular-based diagnostic tools are needed for the implementation of early detection, effective treatments and massive screenings with high-throughput capacities. In this respect, sensitive and affordable devices could greatly impact on sustainable control programmes which exist against parasitic diseases, especially in low income settings. Proteomics and nanotechnology approaches are valuable tools for sensing pathogens and host alteration signatures within microfluidic detection platforms. These new devices might provide novel solutions to fight parasitic diseases. Newly described specific parasite derived products with immune-modulatory properties have been postulated as the best candidates for the early and accurate detection of parasitic infections as well as for the blockage of parasite development. This review provides the most recent methodological and technological advances with great potential for bio-sensing parasites in their hosts, showing the newest opportunities offered by modern "-omics" and platforms for parasite detection and control. Copyright © 2016 Elsevier B.V. All rights reserved.

Demonstrations of bio-inspired perching landing gear for UAVs

NASA Astrophysics Data System (ADS)

Tieu, Mindy; Michael, Duncan M.; Pflueger, Jeffery B.; Sethi, Manik S.; Shimazu, Kelli N.; Anthony, Tatiana M.; Lee, Christopher L.

2016-04-01

Results are presented which demonstrate the feasibility and performance of two concepts of biologically-inspired landing-gear systems that enable bird-sized, unmanned aerial vehicles (UAV's) to land, perch, and take-off from branchlike structures and/or ledges. The first concept follows the anatomy of birds that can grasp ahold of a branch and perch as tendons in their legs are tensioned. This design involves a gravity-activated, cable-driven, underactuated, graspingfoot mechanism. As the UAV lands, its weight collapses a four-bar linkage pulling a cable which curls two opposing, multi-segmented feet to grasp the landing target. Each foot is a single, compliant mechanism fabricated by simultaneouly 3D-printing a flexible thermo-plastic and a stiffer ABS plastic. The design is optimized to grasp structures over a range of shapes and sizes. Quasi-static and flight tests of this landing gear affixed to RC rotorcraft (24 cm to 550 cm in diameter) demonstrate that the aircraft can land, perch, and take-off from a tree branch, rectangular wood board, PVC pipe, metal hand rail, chair armrest, and in addition, a stone wall ledge. Stability tests show that perching is maintained under base and wind disturbances. The second design concept, inspired by roosting bats, is a two-material, 3D-printed hooking mechanism that enables the UAV to stably suspend itself from a wire or small-diameter branch. The design balances structural stiffness for support and flexibility for the perching process. A flight-test demonstrates the attaching and dis-engaging of a small, RC quadcopter from a suspended line.

Bio-Inspired Extreme Wetting Surfaces for Biomedical Applications

PubMed Central

Shin, Sera; Seo, Jungmok; Han, Heetak; Kang, Subin; Kim, Hyunchul; Lee, Taeyoon

2016-01-01

Biological creatures with unique surface wettability have long served as a source of inspiration for scientists and engineers. More specifically, materials exhibiting extreme wetting properties, such as superhydrophilic and superhydrophobic surfaces, have attracted considerable attention because of their potential use in various applications, such as self-cleaning fabrics, anti-fog windows, anti-corrosive coatings, drag-reduction systems, and efficient water transportation. In particular, the engineering of surface wettability by manipulating chemical properties and structure opens emerging biomedical applications ranging from high-throughput cell culture platforms to biomedical devices. This review describes design and fabrication methods for artificial extreme wetting surfaces. Next, we introduce some of the newer and emerging biomedical applications using extreme wetting surfaces. Current challenges and future prospects of the surfaces for potential biomedical applications are also addressed. PMID:28787916

BATMAV - A Bio-Inspired Micro-Aerial Vehicle for Flapping Flight

NASA Astrophysics Data System (ADS)

Bunget, Gheorghe

The main objective of the BATMAV project is the development of a biologically-inspired Micro Aerial Vehicle (MAV) with flexible and foldable wings for flapping flight. While flapping flight in MAV has been previously studied and a number of models were realized they usually had unfoldable wings actuated with DC motors and mechanical transmission to achieve flapping motion. This approach limits the system to a rather small number of degrees of freedom with little flexibility and introduces an additional disadvantage of a heavy flight platform. The BATMAV project aims at the development of a flight platform that features bat-inspired wings with smart materials-based flexible joints and artificial muscles, which has the potential to closely mimic the kinematics of the real mammalian flyer. The bat-like flight platform was selected after an extensive analysis of morphological and aerodynamic flight parameters of small birds, bats and large insects characterized by a superior maneuverability and wind gust rejection. Morphological and aerodynamic parameters were collected from existing literature and compared concluding that bat wing present a suitable platform that can be actuated efficiently using artificial muscles. Due to their wing camber variation, the bat species can operate effectively at a large range of speeds and exhibit a remarkably maneuverable and agile flight. Although numerous studies were recently investigated the flapping flight, flexible and foldable wings that reproduce the natural intricate and efficient flapping motion were not designed yet. A comprehensive analysis of flight styles in bats based on the data collected by Norberg (Norberg, 1976) and the engineering theory of robotic manipulators resulted in a 2 and 3-DOF models which managed to mimic the wingbeat cycle of the natural flyer. The flexible joints of the 2 and 2-DOF models were replicated using smart materials like superelastic Shape Memory Alloys (SMA). The results of these kinematic

A bio-inspired device for drag reduction on a three-dimensional model vehicle.

PubMed

Kim, Dongri; Lee, Hoon; Yi, Wook; Choi, Haecheon

2016-03-10

In this paper, we introduce a bio-mimetic device for the reduction of the drag force on a three-dimensional model vehicle, the Ahmed body (Ahmed et al 1984 SAE Technical Paper 840300). The device, called automatic moving deflector (AMD), is designed inspired by the movement of secondary feathers on bird's wing suction surface: i.e., secondary feathers pop up when massive separation occurs on bird's wing suction surface at high angles of attack, which increases the lift force at landing. The AMD is applied to the rear slanted surface of the Ahmed body to control the flow separation there. The angle of the slanted surface considered is 25° at which the drag coefficient on the Ahmed body is highest. The wind tunnel experiment is conducted at Re H  = 1.0 × 10(5)-3.8 × 10(5), based on the height of the Ahmed body (H) and the free-stream velocity (U ∞). Several AMDs of different sizes and materials are tested by measuring the drag force on the Ahmed body, and showed drag reductions up to 19%. The velocity and surface-pressure measurements show that AMD starts to pop up when the pressure in the thin gap between the slanted surface and AMD is much larger than that on the upper surface of AMD. We also derive an empirical formula that predicts the critical free-stream velocity at which AMD starts to operate. Finally, it is shown that the drag reduction by AMD is mainly attributed to a pressure recovery on the slanted surface by delaying the flow separation and suppressing the strength of the longitudinal vortices emanating from the lateral edges of the slanted surface.

Folic acid bio-inspired route for facile synthesis of AuPt nanodendrites as enhanced electrocatalysts for methanol and ethanol oxidation reactions

NASA Astrophysics Data System (ADS)

Wang, Ai-Jun; Ju, Ke-Jian; Zhang, Qian-Li; Song, Pei; Wei, Jie; Feng, Jiu-Ju

2016-09-01

Folic acid (FA), as an important biomolecule in cell division and growth, is firstly employed as the structure director and stabilizing agent for controlled synthesis of uniform Au65Pt35 nanodendrites (NDs) by a one-pot wet-chemical bio-inspired route at room temperature. No pre-seed, template, organic solvent, polymer, surfactant or complex instrument is involved. The products are mainly characterized by transmission electron microscopy (TEM), high angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), X-ray diffraction (XRD), and X-Ray photoelectron spectroscopy (XPS). The architectures have enlarged electrochemically active surface area (60.6 m2 gPt-1), enhanced catalytic activity and durability for methanol and ethanol oxidation in contrast with commercial Pt black and the other AuPt alloys by tuning the molar ratios of Au to Pt (e.g., Au31Pt69 and Au82Pt18 nanoparticles). This strategy would be applied to fabricate other bimetallic nanocatalysts in fuel cells.

Fly-ear inspired acoustic sensors for gunshot localization

NASA Astrophysics Data System (ADS)

Liu, Haijun; Currano, Luke; Gee, Danny; Yang, Benjamin; Yu, Miao

2009-05-01

The supersensitive ears of the parasitoid fly Ormia ochracea have inspired researchers to develop bio-inspired directional microphone for sound localization. Although the fly ear is optimized for localizing the narrow-band calling song of crickets at 5 kHz, experiments and simulation have shown that it can amplify directional cues for a wide frequency range. In this article, a theoretical investigation is presented to study the use of fly-ear inspired directional microphones for gunshot localization. Using an equivalent 2-DOF model of the fly ear, the time responses of the fly ear structure to a typical shock wave are obtained and the associated time delay is estimated by using cross-correlation. Both near-field and far-field scenarios are considered. The simulation shows that the fly ear can greatly amplify the time delay by ~20 times, which indicates that with an interaural distance of only 1.2 mm the fly ear is able to generate a time delay comparable to that obtained by a conventional microphone pair with a separation as large as 24 mm. Since the parameters of the fly ear structure can also be tuned for muzzle blast and other impulse stimulus, fly-ear inspired acoustic sensors offers great potential for developing portable gunshot localization systems.

Analysis of the resistive network in a bio-inspired CMOS vision chip

NASA Astrophysics Data System (ADS)

Kong, Jae-Sung; Sung, Dong-Kyu; Hyun, Hyo-Young; Shin, Jang-Kyoo

2007-12-01

CMOS vision chips for edge detection based on a resistive circuit have recently been developed. These chips help develop neuromorphic systems with a compact size, high speed of operation, and low power dissipation. The output of the vision chip depends dominantly upon the electrical characteristics of the resistive network which consists of a resistive circuit. In this paper, the body effect of the MOSFET for current distribution in a resistive circuit is discussed with a simple model. In order to evaluate the model, two 160×120 CMOS vision chips have been fabricated by using a standard CMOS technology. The experimental results have been nicely matched with our prediction.

Design of gecko-inspired fibrillar surfaces with strong attachment and easy-removal properties: a numerical analysis of peel-zone

PubMed Central

Zhou, Ming; Pesika, Noshir; Zeng, Hongbo; Wan, Jin; Zhang, Xiangjun; Meng, Yonggang; Wen, Shizhu; Tian, Yu

2012-01-01

Despite successful fabrication of gecko-inspired fibrillar surfaces with strong adhesion forces, how to achieve an easy-removal property becomes a major concern that may restrict the wide applications of these bio-inspired surfaces. Research on how geckos detach rapidly has inspired the design of novel adhesive surfaces with strong and reversible adhesion capabilities, which relies on further fundamental understanding of the peeling mechanisms. Recent studies showed that the peel-zone plays an important role in the peeling off of adhesive tapes or fibrillar surfaces. In this study, a numerical method was developed to evaluate peel-zone deformation and the resulting mechanical behaviour due to the deformations of fibrillar surfaces detaching from a smooth rigid substrate. The effect of the geometrical parameters of pillars and the stiffness of backing layer on the peel-zone and peel strength, and the strong attachment and easy-removal properties have been analysed to establish a design map for bio-inspired fibrillar surfaces, which shows that the optimized strong attachment and easy-removal properties can vary by over three orders of magnitude. The adhesion and peeling design map established provides new insights into the design and development of novel gecko-inspired fibrillar surfaces. PMID:22572030

Bio-Aerosol Detection Using Mass Spectrometry: Public Health Applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ludvigson, Laura D.

2004-01-01

I recently spent a summer as an intern at the Lawrence Livermore National Laboratory. I worked on a project involving the real-time, reagentless, single cell detection of aerosolized pathogens using a novel mass spectrometry approach called Bio-Aerosol Mass Spectrometry (BAMS). Based upon preliminary results showing the differentiation capabilities of BAMS, I would like to explore the development and use of this novel detection system in the context of both environmental and clinical sample pathogen detection. I would also like to explore the broader public health applications that a system such as BAMS might have in terms of infectious disease preventionmore » and control. In order to appreciate the potential of this instrument, I will demonstrate the need for better pathogen detection methods, and outline the instrumentation, data analysis and preliminary results that lead me toward a desire to explore this technology further. I will also discuss potential experiments for the future along with possible problems that may be encountered along the way.« less

Coaxial electrospinning of WO3 nanotubes functionalized with bio-inspired Pd catalysts and their superior hydrogen sensing performance

NASA Astrophysics Data System (ADS)

Choi, Seon-Jin; Chattopadhyay, Saptarshi; Kim, Jae Jin; Kim, Sang-Joon; Tuller, Harry L.; Rutledge, Gregory C.; Kim, Il-Doo

2016-04-01

Macroporous WO3 nanotubes (NTs) functionalized with nanoscale catalysts were fabricated using coaxial electrospinning combined with sacrificial templating and protein-encapsulated catalysts. The macroporous thin-walled nanotubular structures were obtained by introducing colloidal polystyrene (PS) particles to a shell solution of W precursor and poly(vinylpyrrolidone). After coaxial electrospinning with a core liquid of mineral oil and subsequent calcination, open pores with an average diameter of 173 nm were formed on the surface of WO3 NTs due to decomposition of the PS colloids. In addition, catalytic Pd nanoparticles (NPs) were synthesized using bio-inspired protein cages, i.e., apoferritin, and uniformly dispersed within the shell solution and subsequently on the WO3 NTs. The resulting Pd functionalized macroporous WO3 NTs were demonstrated to be high performance hydrogen (H2) sensors. In particular, Pd-functionalized macroporous WO3 NTs exhibited a very high H2 response (Rair/Rgas) of 17.6 at 500 ppm with a short response time. Furthermore, the NTs were shown to be highly selective for H2 compared to other gases such as carbon monoxide (CO), ammonia (NH3), and methane (CH4). The results demonstrate a new synthetic method to prepare highly porous nanotubular structures with well-dispersed nanoscale catalysts, which can provide improved microstructures for chemical sensing.Macroporous WO3 nanotubes (NTs) functionalized with nanoscale catalysts were fabricated using coaxial electrospinning combined with sacrificial templating and protein-encapsulated catalysts. The macroporous thin-walled nanotubular structures were obtained by introducing colloidal polystyrene (PS) particles to a shell solution of W precursor and poly(vinylpyrrolidone). After coaxial electrospinning with a core liquid of mineral oil and subsequent calcination, open pores with an average diameter of 173 nm were formed on the surface of WO3 NTs due to decomposition of the PS colloids. In addition

Peristaltic Wave Locomotion and Shape Morphing with a Millipede Inspired System

NASA Astrophysics Data System (ADS)

Spinello, Davide; Fattahi, Javad S.

2017-08-01

We present the mechanical model of a bio-inspired deformable system, modeled as a Timoshenko beam, which is coupled to a substrate by a system of distributed elements. The locomotion action is inspired by the coordinated motion of coupling elements that mimic the legs of millipedes and centipedes, whose leg-to-ground contact can be described as a peristaltic displacement wave. The multi-legged structure is crucial in providing redundancy and robustness in the interaction with unstructured environments and terrains. A Lagrangian approach is used to derive the governing equations of the system that couple locomotion and shape morphing. Features and limitations of the model are illustrated with numerical simulations.

A bio-inspired real-time capable artificial lateral line system for freestream flow measurements.

PubMed

Abels, C; Qualtieri, A; De Vittorio, M; Megill, W M; Rizzi, F

2016-06-03

To enhance today's artificial flow sensing capabilities in aerial and underwater robotics, future robots could be equipped with a large number of miniaturized sensors distributed over the surface to provide high resolution measurement of the surrounding fluid flow. In this work we show a linear array of closely separated bio-inspired micro-electro-mechanical flow sensors whose sensing mechanism is based on a piezoresistive strain-gauge along a stress-driven cantilever beam, mimicking the biological superficial neuromasts found in the lateral line organ of fishes. Aiming to improve state-of-the-art flow sensing capability in autonomously flying and swimming robots, our artificial lateral line system was designed and developed to feature multi-parameter freestream flow measurements which provide information about (1) local flow velocities as measured by the signal amplitudes from the individual cantilevers as well as (2) propagation velocity, (3) linear forward/backward direction along the cantilever beam orientation and (4) periodicity of pulses or pulse trains determined by cross-correlating sensor signals. A real-time capable cross-correlation procedure was developed which makes it possible to extract freestream flow direction and velocity information from flow fluctuations. The computed flow velocities deviate from a commercial system by 0.09 m s(-1) at 0.5 m s(-1) and 0.15 m s(-1) at 1.0 m s(-1) flow velocity for a sampling rate of 240 Hz and a sensor distance of 38 mm. Although experiments were performed in air, the presented flow sensing system can be applied to underwater vehicles as well, once the sensors are embedded in a waterproof micro-electro-mechanical systems package.

Field Test Data for Detecting Vibrations of a Building Using High-Speed Video Cameras

DTIC Science & Technology

2017-10-01

ARL-TR-8185 ● OCT 2017 US Army Research Laboratory Field Test Data for Detecting Vibrations of a Building Using High -Speed Video...Field Test Data for Detecting Vibrations of a Building Using High -Speed Video Cameras by Caitlin P Conn and Geoffrey H Goldman Sensors and...June 2016 – October 2017 4. TITLE AND SUBTITLE Field Test Data for Detecting Vibrations of a Building Using High -Speed Video Cameras 5a. CONTRACT

Bio-inspired voltage-dependent calcium channel blockers.

PubMed

Yang, Tingting; He, Lin-Ling; Chen, Ming; Fang, Kun; Colecraft, Henry M

2013-01-01

Ca(2+) influx via voltage-dependent CaV1/CaV2 channels couples electrical signals to biological responses in excitable cells. CaV1/CaV2 channel blockers have broad biotechnological and therapeutic applications. Here we report a general method for developing novel genetically encoded calcium channel blockers inspired by Rem, a small G-protein that constitutively inhibits CaV1/CaV2 channels. We show that diverse cytosolic proteins (CaVβ, 14-3-3, calmodulin and CaMKII) that bind pore-forming α1-subunits can be converted into calcium channel blockers with tunable selectivity, kinetics and potency, simply by anchoring them to the plasma membrane. We term this method 'channel inactivation induced by membrane-tethering of an associated protein' (ChIMP). ChIMP is potentially extendable to small-molecule drug discovery, as engineering FK506-binding protein into intracellular sites within CaV1.2-α1C permits heterodimerization-initiated channel inhibition with rapamycin. The results reveal a universal method for developing novel calcium channel blockers that may be extended to develop probes for a broad cohort of unrelated ion channels.

Programmable snapping composites with bio-inspired architecture.

PubMed

Schmied, Jascha U; Le Ferrand, Hortense; Ermanni, Paolo; Studart, André R; Arrieta, Andres F

2017-03-13

The development of programmable self-shaping materials enables the onset of new and innovative functionalities in many application fields. Commonly, shape adaptation is achieved by exploiting diffusion-driven swelling or nano-scale phase transition, limiting the change of shape to slow motion predominantly determined by the environmental conditions and/or the materials specificity. To address these shortcomings, we report shape adaptable programmable shells that undergo morphing via a snap-through mechanism inspired by the Dionaea muscipula leaf, known as the Venus fly trap. The presented shells are composite materials made of epoxy reinforced by stiff anisotropic alumina micro-platelets oriented in specific directions. By tailoring the microstructure via magnetically-driven alignment of the platelets, we locally tune the pre-strain and stiffness anisotropy of the composite. This novel approach enables the fabrication of complex shapes showing non-orthotropic curvatures and stiffness gradients, radically extending the design space when compared to conventional long-fibre reinforced multi-stable composites. The rare combination of large stresses, short actuation times and complex shapes, results in hinge-free artificial shape adaptable systems with large design freedom for a variety of morphing applications.

A Mechanism for Error Detection in Speeded Response Time Tasks

ERIC Educational Resources Information Center

Holroyd, Clay B.; Yeung, Nick; Coles, Michael G. H.; Cohen, Jonathan D.

2005-01-01

The concept of error detection plays a central role in theories of executive control. In this article, the authors present a mechanism that can rapidly detect errors in speeded response time tasks. This error monitor assigns values to the output of cognitive processes involved in stimulus categorization and response generation and detects errors…

High-performance mussel-inspired adhesives of reduced complexity.

PubMed

Ahn, B Kollbe; Das, Saurabh; Linstadt, Roscoe; Kaufman, Yair; Martinez-Rodriguez, Nadine R; Mirshafian, Razieh; Kesselman, Ellina; Talmon, Yeshayahu; Lipshutz, Bruce H; Israelachvili, Jacob N; Waite, J Herbert

2015-10-19

Despite the recent progress in and demand for wet adhesives, practical underwater adhesion remains limited or non-existent for diverse applications. Translation of mussel-inspired wet adhesion typically entails catechol functionalization of polymers and/or polyelectrolytes, and solution processing of many complex components and steps that require optimization and stabilization. Here we reduced the complexity of a wet adhesive primer to synthetic low-molecular-weight catecholic zwitterionic surfactants that show very strong adhesion (∼50 mJ m(-2)) and retain the ability to coacervate. This catecholic zwitterion adheres to diverse surfaces and self-assembles into a molecularly smooth, thin (<4 nm) and strong glue layer. The catecholic zwitterion holds particular promise as an adhesive for nanofabrication. This study significantly simplifies bio-inspired themes for wet adhesion by combining catechol with hydrophobic and electrostatic functional groups in a small molecule.

Synthesis and bio-inspired optimization of drimenal: Discovery of chiral drimane fused oxazinones as promising antifungal and antibacterial candidates.

PubMed

Li, Dangdang; Zhang, Shasha; Song, Zehua; Li, Wei; Zhu, Feng; Zhang, Jiwen; Li, Shengkun

2018-01-01

The synthesis of antifungal natural product drimenal was accomplished. Bio-inspired optimization protruded chiral 8-(R)-drimane fused oxazinone D as a lead, considering favorable physicochemical profiles for novel pesticides. The improved scalable synthesis of scaffold D was implemented by Hofmann rearrangment under mild conditions. Detailed structural optimization was discussed for both antifungal and antibacterial exploration. Substituted groups (SGs) with C 3 ∼C 5 hydrocarbon chain are recommended for exploration of antifungal agents, while substituents with C 4 ∼C 6 carbon length are preferred for antibacterial ingredients. The chiral drimane fused oxazinone D8 was selected as a promising antifungal candidate against Botrytis cirerea, with an EC 50 value of 1.18 mg/L, with the enhancement of up to >25 folds and >80 folds than the mother compound D, and acyclic counterpart AB5, respectively. The in vivo bioassay confirmed much better preservative effect of D8 than that of Carbendazim. The chiral oxazinone variant D10 possessed prominent antibacterial activity, with MIC values of 8 mg/L against both Bacillus subtilis and Ralstonia solanacearum, showing advantages over the positive control streptomycin sulfate. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Memetic computing through bio-inspired heuristics integration with sequential quadratic programming for nonlinear systems arising in different physical models.

PubMed

Raja, Muhammad Asif Zahoor; Kiani, Adiqa Kausar; Shehzad, Azam; Zameer, Aneela

2016-01-01

In this study, bio-inspired computing is exploited for solving system of nonlinear equations using variants of genetic algorithms (GAs) as a tool for global search method hybrid with sequential quadratic programming (SQP) for efficient local search. The fitness function is constructed by defining the error function for systems of nonlinear equations in mean square sense. The design parameters of mathematical models are trained by exploiting the competency of GAs and refinement are carried out by viable SQP algorithm. Twelve versions of the memetic approach GA-SQP are designed by taking a different set of reproduction routines in the optimization process. Performance of proposed variants is evaluated on six numerical problems comprising of system of nonlinear equations arising in the interval arithmetic benchmark model, kinematics, neurophysiology, combustion and chemical equilibrium. Comparative studies of the proposed results in terms of accuracy, convergence and complexity are performed with the help of statistical performance indices to establish the worth of the schemes. Accuracy and convergence of the memetic computing GA-SQP is found better in each case of the simulation study and effectiveness of the scheme is further established through results of statistics based on different performance indices for accuracy and complexity.

Influence of "J"-Curve Spring Stiffness on Running Speeds of Segmented Legs during High-Speed Locomotion.

PubMed

Wang, Runxiao; Zhao, Wentao; Li, Shujun; Zhang, Shunqi

2016-01-01

Both the linear leg spring model and the two-segment leg model with constant spring stiffness have been broadly used as template models to investigate bouncing gaits for legged robots with compliant legs. In addition to these two models, the other stiffness leg spring models developed using inspiration from biological characteristic have the potential to improve high-speed running capacity of spring-legged robots. In this paper, we investigate the effects of "J"-curve spring stiffness inspired by biological materials on running speeds of segmented legs during high-speed locomotion. Mathematical formulation of the relationship between the virtual leg force and the virtual leg compression is established. When the SLIP model and the two-segment leg model with constant spring stiffness and with "J"-curve spring stiffness have the same dimensionless reference stiffness, the two-segment leg model with "J"-curve spring stiffness reveals that (1) both the largest tolerated range of running speeds and the tolerated maximum running speed are found and (2) at fast running speed from 25 to 40/92 m s -1 both the tolerated range of landing angle and the stability region are the largest. It is suggested that the two-segment leg model with "J"-curve spring stiffness is more advantageous for high-speed running compared with the SLIP model and with constant spring stiffness.

Bio-Inspired Multi-Functional Drug Transport Design Concept and Simulations.

PubMed

Pidaparti, Ramana M; Cartin, Charles; Su, Guoguang

2017-04-25

In this study, we developed a microdevice concept for drug/fluidic transport taking an inspiration from supramolecular motor found in biological cells. Specifically, idealized multi-functional design geometry (nozzle/diffuser/nozzle) was developed for (i) fluidic/particle transport; (ii) particle separation; and (iii) droplet generation. Several design simulations were conducted to demonstrate the working principles of the multi-functional device. The design simulations illustrate that the proposed design concept is feasible for multi-functionality. However, further experimentation and optimization studies are needed to fully evaluate the multifunctional device concept for multiple applications.

Bio-logging of physiological parameters in higher marine vertebrates

NASA Astrophysics Data System (ADS)

Ponganis, Paul J.

2007-02-01

Bio-logging of physiological parameters in higher marine vertebrates had its origins in the field of bio-telemetry in the 1960s and 1970s. The development of microprocessor technology allowed its first application to bio-logging investigations of Weddell seal diving physiology in the early 1980s. Since that time, with the use of increased memory capacity, new sensor technology, and novel data processing techniques, investigators have examined heart rate, temperature, swim speed, stroke frequency, stomach function (gastric pH and motility), heat flux, muscle oxygenation, respiratory rate, diving air volume, and oxygen partial pressure (P) during diving. Swim speed, heart rate, and body temperature have been the most commonly studied parameters. Bio-logging investigation of pressure effects has only been conducted with the use of blood samplers and nitrogen analyses on animals diving at isolated dive holes. The advantages/disadvantages and limitations of recording techniques, probe placement, calibration techniques, and study conditions are reviewed.

Label-Free Aptasensors for the Detection of Mycotoxins

PubMed Central

Rhouati, Amina; Catanante, Gaelle; Nunes, Gilvanda; Hayat, Akhtar; Marty, Jean-Louis

2016-01-01

Various methodologies have been reported in the literature for the qualitative and quantitative monitoring of mycotoxins in food and feed samples. Based on their enhanced specificity, selectivity and versatility, bio-affinity assays have inspired many researchers to develop sensors by exploring bio-recognition phenomena. However, a significant problem in the fabrication of these devices is that most of the biomolecules do not generate an easily measurable signal upon binding to the target analytes, and signal-generating labels are required to perform the measurements. In this context, aptamers have been emerged as a potential and attractive bio-recognition element to design label-free aptasensors for various target analytes. Contrary to other bioreceptor-based approaches, the aptamer-based assays rely on antigen binding-induced conformational changes or oligomerization states rather than binding-assisted changes in adsorbed mass or charge. This review will focus on current designs in label-free conformational switchable design strategies, with a particular focus on applications in the detection of mycotoxins. PMID:27999353

A microsensor for the detection of a single pathogenic bacterium using magnetotactic bacteria-based bio-carriers: simulations and preliminary experiments.

PubMed

Denomme, Ryan C; Lu, Zhao; Martel, Sylvain

2007-01-01

The proposed Magnetotactic Bacteria (MTB) based bio-carrier has the potential to greatly improve pathogenic bacteria detection time, specificity, and sensitivity. Microbeads are attached to the MTB and are modified with a coating of an antibody or phage that is specific to the target pathogenic bacteria. Using magnetic fields, the modified MTB are swept through a solution and the target bacteria present become attached to the microbeads (due to the coating). Then, the MTB are brought to the detection region and the number of pathogenic bacteria is determined. The high swimming speed and controllability of the MTB make this method ideal for the fast detection of small concentrations of specific bacteria. This paper focuses on an impedimetric detection system that will be used to identify if a target bacterium is attached to the microbead. The proposed detection system measures changes in electrical impedance as objects (MTB, microbeads, and pathogenic bacteria) pass through a set of microelectrodes embedded in a microfluidic device. FEM simulation is used to acquire the optimized parameters for the design of such a system. Specifically, factors such as electrode/detection channel geometry, object size and position, which have direct effects on the detection sensitivity for a single bacterium or microparticle, are investigated. Polymer microbeads and the MTB system with an E. coli bacterium are considered to investigate their impedance variations. Furthermore, preliminary experimental data using a microfabricated microfluidic device connected to an impedance analyzer are presented.

Influence of “J”-Curve Spring Stiffness on Running Speeds of Segmented Legs during High-Speed Locomotion

PubMed Central

2016-01-01

Both the linear leg spring model and the two-segment leg model with constant spring stiffness have been broadly used as template models to investigate bouncing gaits for legged robots with compliant legs. In addition to these two models, the other stiffness leg spring models developed using inspiration from biological characteristic have the potential to improve high-speed running capacity of spring-legged robots. In this paper, we investigate the effects of “J”-curve spring stiffness inspired by biological materials on running speeds of segmented legs during high-speed locomotion. Mathematical formulation of the relationship between the virtual leg force and the virtual leg compression is established. When the SLIP model and the two-segment leg model with constant spring stiffness and with “J”-curve spring stiffness have the same dimensionless reference stiffness, the two-segment leg model with “J”-curve spring stiffness reveals that (1) both the largest tolerated range of running speeds and the tolerated maximum running speed are found and (2) at fast running speed from 25 to 40/92 m s−1 both the tolerated range of landing angle and the stability region are the largest. It is suggested that the two-segment leg model with “J”-curve spring stiffness is more advantageous for high-speed running compared with the SLIP model and with constant spring stiffness. PMID:28018127

Concepts and Development of Bio-Inspired Distributed Embedded Wired/Wireless Sensor Array Architectures for Acoustic Wave Sensing in Integrated Aerospace Vehicles

NASA Technical Reports Server (NTRS)

Ghoshal, Anindya; Prosser, William H.; Kirikera, Goutham; Schulz, Mark J.; Hughes, Derke J.; Orisamolu, Wally

2003-01-01

This paper discusses the modeling of acoustic emissions in plate structures and their sensing by embedded or surface bonded piezoelectric sensor arrays. Three different modeling efforts for acoustic emission (AE) wave generation and propagation are discussed briefly along with their advantages and disadvantages. Continuous sensors placed at right angles on a plate are being discussed as a new approach to measure and locate the source of acoustic waves. Evolutionary novel signal processing algorithms and bio-inspired distributed sensor array systems are used on large structures and integrated aerospace vehicles for AE source localization and preliminary results are presented. These systems allow for a great reduction in the amount of data that needs to be processed and also reduce the chances of false alarms from ambient noises. It is envisioned that these biomimetic sensor arrays and signal processing techniques will be useful for both wireless and wired sensor arrays for real time health monitoring of large integrated aerospace vehicles and earth fixed civil structures. The sensor array architectures can also be used with other types of sensors and for other applications.

Bio-Inspired Photon Absorption and Energy Transfer for Next Generation Photovoltaic Devices

NASA Astrophysics Data System (ADS)

Magsi, Komal

Nature's solar energy harvesting system, photosynthesis, serves as a model for photon absorption, spectra broadening, and energy transfer. Photosynthesis harvests light far differently than photovoltaic cells. These differences offer both engineering opportunity and scientific challenges since not all of the natural photon absorption mechanisms have been understood. In return, solar cells can be a very sensitive probe for the absorption characteristics of molecules capable of transferring charge to a conductive interface. The objective of this scientific work is the advancement of next generation photovoltaics through the development and application of natural photo-energy transfer processes. Two scientific methods were used in the development and application of enhancing photon absorption and transfer. First, a detailed analysis of photovoltaic front surface fluorescent spectral modification and light scattering by hetero-structure was conducted. Phosphor based spectral down-conversion is a well-known laser technology. The theoretical calculations presented here indicate that parasitic losses and light scattering within the spectral range are large enough to offset any expected gains. The second approach for enhancing photon absorption is based on bio-inspired mechanisms. Key to the utilization of these natural processes is the development of a detailed scientific understanding and the application of these processes to cost effective systems and devices. In this work both aspects are investigated. Dye type solar cells were prepared and tested as a function of Chlorophyll (or Sodium-Copper Chlorophyllin) and accessory dyes. Forster has shown that the fluorescence ratio of Chlorophyll is modified and broadened by separate photon absorption (sensitized absorption) through interaction with nearby accessory pigments. This work used the dye type solar cell as a diagnostic tool by which to investigate photon absorption and photon energy transfer. These experiments shed

High-performance mussel-inspired adhesives of reduced complexity

PubMed Central

Ahn, B. Kollbe; Das, Saurabh; Linstadt, Roscoe; Kaufman, Yair; Martinez-Rodriguez, Nadine R.; Mirshafian, Razieh; Kesselman, Ellina; Talmon, Yeshayahu; Lipshutz, Bruce H.; Israelachvili, Jacob N.; Waite, J. Herbert

2015-01-01

Despite the recent progress in and demand for wet adhesives, practical underwater adhesion remains limited or non-existent for diverse applications. Translation of mussel-inspired wet adhesion typically entails catechol functionalization of polymers and/or polyelectrolytes, and solution processing of many complex components and steps that require optimization and stabilization. Here we reduced the complexity of a wet adhesive primer to synthetic low-molecular-weight catecholic zwitterionic surfactants that show very strong adhesion (∼50 mJ m−2) and retain the ability to coacervate. This catecholic zwitterion adheres to diverse surfaces and self-assembles into a molecularly smooth, thin (<4 nm) and strong glue layer. The catecholic zwitterion holds particular promise as an adhesive for nanofabrication. This study significantly simplifies bio-inspired themes for wet adhesion by combining catechol with hydrophobic and electrostatic functional groups in a small molecule. PMID:26478273

High-Speed Incoming Infrared Target Detection by Fusion of Spatial and Temporal Detectors

PubMed Central

Kim, Sungho

2015-01-01

This paper presents a method for detecting high-speed incoming targets by the fusion of spatial and temporal detectors to achieve a high detection rate for an active protection system (APS). The incoming targets have different image velocities according to the target-camera geometry. Therefore, single-target detector-based approaches, such as a 1D temporal filter, 2D spatial filter and 3D matched filter, cannot provide a high detection rate with moderate false alarms. The target speed variation was analyzed according to the incoming angle and target velocity. The speed of the distant target at the firing time is almost stationary and increases slowly. The speed varying targets are detected stably by fusing the spatial and temporal filters. The stationary target detector is activated by an almost zero temporal contrast filter (TCF) and identifies targets using a spatial filter called the modified mean subtraction filter (M-MSF). A small motion (sub-pixel velocity) target detector is activated by a small TCF value and finds targets using the same spatial filter. A large motion (pixel-velocity) target detector works when the TCF value is high. The final target detection is terminated by fusing the three detectors based on the threat priority. The experimental results of the various target sequences show that the proposed fusion-based target detector produces the highest detection rate with an acceptable false alarm rate. PMID:25815448

An autonomous robot inspired by insect neurophysiology pursues moving features in natural environments

NASA Astrophysics Data System (ADS)

Bagheri, Zahra M.; Cazzolato, Benjamin S.; Grainger, Steven; O'Carroll, David C.; Wiederman, Steven D.

2017-08-01

Objective. Many computer vision and robotic applications require the implementation of robust and efficient target-tracking algorithms on a moving platform. However, deployment of a real-time system is challenging, even with the computational power of modern hardware. Lightweight and low-powered flying insects, such as dragonflies, track prey or conspecifics within cluttered natural environments, illustrating an efficient biological solution to the target-tracking problem. Approach. We used our recent recordings from ‘small target motion detector’ neurons in the dragonfly brain to inspire the development of a closed-loop target detection and tracking algorithm. This model exploits facilitation, a slow build-up of response to targets which move along long, continuous trajectories, as seen in our electrophysiological data. To test performance in real-world conditions, we implemented this model on a robotic platform that uses active pursuit strategies based on insect behaviour. Main results. Our robot performs robustly in closed-loop pursuit of targets, despite a range of challenging conditions used in our experiments; low contrast targets, heavily cluttered environments and the presence of distracters. We show that the facilitation stage boosts responses to targets moving along continuous trajectories, improving contrast sensitivity and detection of small moving targets against textured backgrounds. Moreover, the temporal properties of facilitation play a useful role in handling vibration of the robotic platform. We also show that the adoption of feed-forward models which predict the sensory consequences of self-movement can significantly improve target detection during saccadic movements. Significance. Our results provide insight into the neuronal mechanisms that underlie biological target detection and selection (from a moving platform), as well as highlight the effectiveness of our bio-inspired algorithm in an artificial visual system.

Superhydrophobic gecko feet with high adhesive forces towards water and their bio-inspired materials.

PubMed

Liu, Kesong; Du, Jiexing; Wu, Juntao; Jiang, Lei

2012-02-07

Functional integration is an inherent characteristic for multiscale structures of biological materials. In this contribution, we first investigate the liquid-solid adhesive forces between water droplets and superhydrophobic gecko feet using a high-sensitivity micro-electromechanical balance system. It was found, in addition to the well-known solid-solid adhesion, the gecko foot, with a multiscale structure, possesses both superhydrophobic functionality and a high adhesive force towards water. The origin of the high adhesive forces of gecko feet to water could be attributed to the high density nanopillars that contact the water. Inspired by this, polyimide films with gecko-like multiscale structures were constructed by using anodic aluminum oxide templates, exhibiting superhydrophobicity and a strong adhesive force towards water. The static water contact angle is larger than 150° and the adhesive force to water is about 66 μN. The resultant gecko-inspired polyimide film can be used as a "mechanical hand" to snatch micro-liter liquids. We expect this work will provide the inspiration to reveal the mechanism of the high-adhesive superhydrophobic of geckos and extend the practical applications of polyimide materials. This journal is © The Royal Society of Chemistry 2012

Nanoblinker: Brownian Motion Powered Bio-Nanomachine for FRET Detection of Phagocytic Phase of Apoptosis

PubMed Central

Minchew, Candace L.; Didenko, Vladimir V.

2014-01-01

We describe a new type of bio-nanomachine which runs on thermal noise. The machine is solely powered by the random motion of water molecules in its environment and does not ever require re-fuelling. The construct, which is made of DNA and vaccinia virus topoisomerase protein, can detect DNA damage by employing fluorescence. It uses Brownian motion as a cyclic motor to continually separate and bring together two types of fluorescent hairpins participating in FRET. This bio-molecular oscillator is a fast and specific sensor of 5′OH double-strand DNA breaks present in phagocytic phase of apoptosis. The detection takes 30 s in solution and 3 min in cell suspensions. The phagocytic phase is critical for the effective execution of apoptosis as it ensures complete degradation of the dying cells’ DNA, preventing release of pathological, viral and tumor DNA and self-immunization. The construct can be used as a smart FRET probe in studies of cell death and phagocytosis. PMID:25268504

Mussel-inspired tough hydrogels with self-repairing and tissue adhesion

NASA Astrophysics Data System (ADS)

Gao, Zijian; Duan, Lijie; Yang, Yongqi; Hu, Wei; Gao, Guanghui

2018-01-01

The mussel-inspired polymeric hydrogels have been attractively explored owing to their self-repairing or adhesive property when the catechol groups of dopamine could chelate metal ions. However, it was a challenge for self-repairing hydrogels owning high mechanical properties. Herein, a synergistic strategy was proposed by combining catechol-Fe3+ complexes and hydrophobic association. The resulting hydrogels exhibited seamless self-repairing behavior, tissue adhesion and high mechanical property. Moreover, the pH-dependent stoichiometry of catechol-Fe3+ and temperature-sensitive hydrophobic association endue hydrogels with pH/thermo responsive characteristics. Subsequently, the self-repairing rate and mechanical property of hydrogels were investigated at different pH and temperature. This bio-inspired strategy would build an avenue for designing and constructing a new generation of self-repairing, tissue-adhesive and tough hydrogel.

Bio-robots automatic navigation with graded electric reward stimulation based on Reinforcement Learning.

PubMed

Zhang, Chen; Sun, Chao; Gao, Liqiang; Zheng, Nenggan; Chen, Weidong; Zheng, Xiaoxiang

2013-01-01

Bio-robots based on brain computer interface (BCI) suffer from the lack of considering the characteristic of the animals in navigation. This paper proposed a new method for bio-robots' automatic navigation combining the reward generating algorithm base on Reinforcement Learning (RL) with the learning intelligence of animals together. Given the graded electrical reward, the animal e.g. the rat, intends to seek the maximum reward while exploring an unknown environment. Since the rat has excellent spatial recognition, the rat-robot and the RL algorithm can convergent to an optimal route by co-learning. This work has significant inspiration for the practical development of bio-robots' navigation with hybrid intelligence.

Dye@bio-MOF-1 Composite as a Dual-Emitting Platform for Enhanced Detection of a Wide Range of Explosive Molecules.

PubMed

Wang, Chen; Tian, Li; Zhu, Wei; Wang, Shiqiang; Wang, Peng; Liang, Yun; Zhang, Wanlin; Zhao, Hongwei; Li, Guangtao

2017-06-14

By incorporating a cationic dye within a metal-organic framework (MOF) through an ion-exchange process, a responsive dye@bio-MOF-1 composite has been synthesized, serving as a dual-emitting platform for enhanced detection of different kinds of nitro-explosives, especially nitroalkanes, nitramines, and nitrate esters. The dye@bio-MOF-1 composite was constructed with free amines on their well-defined cavities, which is essential for the capture of explosives into their confined nanospace. It was observed that the encapsulation of explosives into the constructed dye@bio-MOF-1 composite could dramatically alter the luminescent properties of the dyes as well as the MOF skeletons owing to the size exclusivity and confinement-induced effect. For nitroaromatics, the dye@bio-MOF-1 composite exhibits turn-off responses via fluorescence quenching. Unexpectedly, the composite shows unique turn-on responses for aliphatic nitro-organics via confinement-induced enhancement, demonstrating enhanced ability to detecting different kinds of explosives selectively in aqueous solution. Furthermore, the dye@bio-MOF-1 film was facilely fabricated, making the chemical sensing more convenient and easier to realize the discrimination of the targeted explosives. The dual tunable responses indicate that dye@bio-MOF-1 composites are favorable materials for molecular sensing. On the basis of the host-guest properties of the constructed dye@bio-MOF-1 composite, our work can be further extended to sensing specific analytes with remarkable turn-on sensing properties, in particular those difficult to recognize with conventional methods.

Bio-Inspired Fluoro-polydopamine Meets Barium Titanate Nanowires: A Perfect Combination to Enhance Energy Storage Capability of Polymer Nanocomposites.

PubMed

Wang, Guanyao; Huang, Xingyi; Jiang, Pingkai

2017-03-01

Rapid evolution of energy storage devices expedites the development of high-energy-density materials with excellent flexibility and easy processing. The search for such materials has triggered the development of high-dielectric-constant (high-k) polymer nanocomposites. However, the enhancement of k usually suffers from sharp reduction of breakdown strength, which is detrimental to substantial increase of energy storage capability. Herein, the combination of bio-inspired fluoro-polydopamine functionalized BaTiO 3 nanowires (NWs) and a fluoropolymer matrix offers a new thought to prepare polymer nanocomposites. The elaborate functionalization of BaTiO 3 NWs with fluoro-polydopamine has guaranteed both the increase of k and the maintenance of breakdown strength, resulting in significantly enhanced energy storage capability. The nanocomposite with 5 vol % functionalized BaTiO 3 NWs discharges an ultrahigh energy density of 12.87 J cm -3 at a relatively low electric field of 480 MV m -1 , more than three and a half times that of biaxial-oriented polypropylene (BOPP, 3.56 J cm -3 at 600 MV m -1 ). This superior energy storage capability seems to rival or exceed some reported advanced nanoceramics-based materials at 500 MV m -1 . This new strategy permits insights into the construction of polymer nanocomposites with high energy storage capability.

Mimicking the cell membrane: bio-inspired simultaneous functions with monovalent anion selectivity and antifouling properties of anion exchange membrane

PubMed Central

Zhao, Yan; Liu, Huimin; Tang, Kaini; Jin, Yali; Pan, Jiefeng; der Bruggen, Bart Van; Shen, Jiangnan; Gao, Congjie

2016-01-01

A new bio-inspired method was applied in this study to simultaneously improve the monovalent anion selectivity and antifouling properties of anion exchange membranes (AEMs). Three-layer architecture was developed by deposition of polydopamine (PDA) and electro-deposition of N-O-sulfonic acid benzyl chitosan (NSBC). The innermost and outermost layers were PDA with different deposition time. The middle layer was prepared by NSBC. Fourier transform infrared spectroscopy and scanning electron microscopy confirmed that PDA and NSBC were successfully modified on the surfaces of AEMs. The contact angle of the membranes indicated an improved hydrophilicity of the modified membranes. A series of electrodialysis experiments in which Cl−/SO42− separation was studied, demonstrating the monovalent anion selectivity of the samples. The Cl−/SO42− permselectivity of the modified membranes can reach up to 2.20, higher than that of the commercial membrane (only 0.78) during 90 minutes in electrodialysis (ED). The increase value of the resistance of the membranes was also measured to evaluate the antifouling properties. Sodium dodecyl benzene sulfonate (SDBS) was used as the fouling material in the ED process and the membrane area resistance of modified membrane increase value of was only 0.08 Ωcm2 30 minutes later. PMID:27853255

Mimicking the cell membrane: bio-inspired simultaneous functions with monovalent anion selectivity and antifouling properties of anion exchange membrane.

PubMed

Zhao, Yan; Liu, Huimin; Tang, Kaini; Jin, Yali; Pan, Jiefeng; der Bruggen, Bart Van; Shen, Jiangnan; Gao, Congjie

2016-11-17

A new bio-inspired method was applied in this study to simultaneously improve the monovalent anion selectivity and antifouling properties of anion exchange membranes (AEMs). Three-layer architecture was developed by deposition of polydopamine (PDA) and electro-deposition of N-O-sulfonic acid benzyl chitosan (NSBC). The innermost and outermost layers were PDA with different deposition time. The middle layer was prepared by NSBC. Fourier transform infrared spectroscopy and scanning electron microscopy confirmed that PDA and NSBC were successfully modified on the surfaces of AEMs. The contact angle of the membranes indicated an improved hydrophilicity of the modified membranes. A series of electrodialysis experiments in which Cl - /SO 4 2- separation was studied, demonstrating the monovalent anion selectivity of the samples. The Cl - /SO 4 2- permselectivity of the modified membranes can reach up to 2.20, higher than that of the commercial membrane (only 0.78) during 90 minutes in electrodialysis (ED). The increase value of the resistance of the membranes was also measured to evaluate the antifouling properties. Sodium dodecyl benzene sulfonate (SDBS) was used as the fouling material in the ED process and the membrane area resistance of modified membrane increase value of was only 0.08 Ωcm 2 30 minutes later.

Mimicking the cell membrane: bio-inspired simultaneous functions with monovalent anion selectivity and antifouling properties of anion exchange membrane

NASA Astrophysics Data System (ADS)

Zhao, Yan; Liu, Huimin; Tang, Kaini; Jin, Yali; Pan, Jiefeng; der Bruggen, Bart Van; Shen, Jiangnan; Gao, Congjie

2016-11-01

A new bio-inspired method was applied in this study to simultaneously improve the monovalent anion selectivity and antifouling properties of anion exchange membranes (AEMs). Three-layer architecture was developed by deposition of polydopamine (PDA) and electro-deposition of N-O-sulfonic acid benzyl chitosan (NSBC). The innermost and outermost layers were PDA with different deposition time. The middle layer was prepared by NSBC. Fourier transform infrared spectroscopy and scanning electron microscopy confirmed that PDA and NSBC were successfully modified on the surfaces of AEMs. The contact angle of the membranes indicated an improved hydrophilicity of the modified membranes. A series of electrodialysis experiments in which Cl-/SO42- separation was studied, demonstrating the monovalent anion selectivity of the samples. The Cl-/SO42- permselectivity of the modified membranes can reach up to 2.20, higher than that of the commercial membrane (only 0.78) during 90 minutes in electrodialysis (ED). The increase value of the resistance of the membranes was also measured to evaluate the antifouling properties. Sodium dodecyl benzene sulfonate (SDBS) was used as the fouling material in the ED process and the membrane area resistance of modified membrane increase value of was only 0.08 Ωcm2 30 minutes later.

A Systems Approach to Bio-Oil Stabilization - Final Technical Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brown, Robert C; Meyer, Terrence; Fox, Rodney

2011-12-23

products: condensable vapors, non-condensable gases, and liquid aerosols. Traditionally these are recovered by a spray quencher or a conventional shell and tube condenser. The spray quencher or condenser is typically followed by an electrostatic precipitator to yield 1 or 2 distinct fractions of bio-oil. The pyrolyzer system developed at Iowa State University incorporates a proprietary fractionating condenser train. The system collects the bio-oil into five unique fractions. For conditions typical of fluidized bed pyrolyzers, stage fractions have been collected that are carbohydrate-rich (anhydrosugars), lignin-rich, and an aqueous solution of carboxylic acids and aldehydes. One important feature is that most of the water normally found in bio-oil appears in the last stage fraction along with several water-soluble components that are thought to be responsible for bio-oil aging (low molecular weight carboxylic acids and aldehydes). Research work on laser diagnostics for hot-vapor filtration and bio-oil recovery centered on development of analytical techniques for in situ measurements during fast pyrolysis, hot-vapor filtration, and fractionation relative to bio-oil stabilization. The methods developed in this work include laser-induced breakdown spectroscopy (LIBS), laser-induced incandescence (LII), and laser scattering for elemental analysis (N, O, H, C), detection of particulates, and detection of aerosols, respectively. These techniques were utilized in simulated pyrolysis environments and applied to a small-scale pyrolysis unit. Stability of Bio-oils is adversely affected by the presence of particulates that are formed as a consequence of thermal pyrolysis, improving the CFD simulations of moving bed granular filter (MBGF) is useful for improving the design of MBGF for bio-oil production. The current work uses fully resolved direct numerical simulation (where the flow past each granule is accurately represented) to calculate the filter efficiency that is used in the

Bio-inspired green synthesis of Fe3O4 magnetic nanoparticles using watermelon rinds and their catalytic activity

NASA Astrophysics Data System (ADS)

Prasad, Ch.; Gangadhara, S.; Venkateswarlu, P.

2016-08-01

Novel and bio-inspired magnetic nanoparticles were synthesized using watermelon rinds (WR) which are nontoxic and biodegradable. Watermelon rind extract was used as a solvent and capping and reducing agent in the synthesis. The Fe3o4 MNPs were characterized by using transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and vibrating sample magnetometer techniques (VSM). XRD studies revealed a high degree of crystalline and monophasic Fe nanoparticles of face-centered cubic stricture. FTIR analysis proved that particles are reduced and stabilized in solution by the capping agent that is likely to be proteins secreted by the biomass. The present process in an excellent candidate for the synthesis of iron nanoparticles that is simple, easy to execute, pollutant free and inexpensive. A practical and convenient method for the synthesis of highly stable and small-sized iron nanoparticles with a narrow distribution from 2 to 20 nm is reported. Also, the MNPs present in higher saturation magnetization (Ms) of 14.2 emu/g demonstrate tremendous magnetic response behavior. However, the synthesized iron nanoparticles were used as a catalyst for the preparation of biologically interesting 2-oxo-1,2,3,4-tetrahydropyrimidine derivatives in high yields. These results exhibited that the synthesized Fe3O4 MNPs could be used as a catalyst in organic synthesis.

Material-specific detection and classification of single nanoparticles

PubMed Central

Person, Steven; Deutsch, Bradley; Mitra, Anirban; Novotny, Lukas

2010-01-01

Detection and classification of nanoparticles is important for environmental monitoring, contamination mitigation, biological label tracking, and bio-defense. Detection techniques involve a trade-off between sensitivity, discrimination, and speed. This paper presents a material-specific dual-color common-path interferometric detection system. Two wavelengths are simultaneously used to discriminate between 60 nm silver and 80 nm diameter gold particles in solution with a detection time of τ ≈ 1 ms. The detection technique is applicable to situations where both particle size and material are of interest. PMID:21142033

Helicopter main-rotor speed effects: A comparison of predicted ranges of detection from the aural detection program ICHIN and the electronic detection program ARCAS

NASA Technical Reports Server (NTRS)

Mueller, Arnold W.; Smith, Charles D.

1991-01-01

NASA LaRC personnel have conducted a strudy of the predicted acoustic detection ranges associated with reduced helicopter main rotor speeds. This was accomplished by providing identical input information to both the aural detection program ICHIN 6, (I Can Hear It Now, version 6) and the electronic acoustic detection program ARCAS (Assessment of Rotorcraft Detection by Acoustics Sensing). In this study, it was concluded that reducing the main rotor speed of the helicopter by 27 percent reduced both the predicted aural and electronic detection ranges by approximately 50 percent. Additionally, ARCAS was observed to function better with narrowband spectral input than with one-third octave band spectral inputs and the predicted electronic range of acoustic detection is greater than the predicted aural detection range.

Physical activity monitoring: addressing the difficulties of accurately detecting slow walking speeds.

PubMed

Harrison, Samantha L; Horton, Elizabeth J; Smith, Robert; Sandland, Carolyn J; Steiner, Michael C; Morgan, Mike D L; Singh, Sally J

2013-01-01

To test the accuracy of a multi-sensor activity monitor (SWM) in detecting slow walking speeds in patients with chronic obstructive pulmonary disease (COPD). Concerns have been expressed regarding the use of pedometers in patient populations. Although activity monitors are more sophisticated devices, their accuracy at detecting slow walking speeds common in patients with COPD has yet to be proven. A prospective observational study design was employed. An incremental shuttle walk test (ISWT) was completed by 57 patients with COPD wearing an SWM. The ISWT was repeated by 20 patients wearing the same SWM. Differences were identified between metabolic equivalents (METS) and between step-count across five levels of the ISWT (p < 0.001). Good within monitor reproducibility between two ISWT was identified for total energy expenditure and step-count (p < 0.001). The SWM is able to detect slow (standardized) speeds of walking and is an acceptable method for measuring physical activity in individuals disabled by COPD. Copyright © 2013 Elsevier Inc. All rights reserved.

Isolated nanoinjection photo detectors for high-speed and high-sensitivity single-photon detection

NASA Astrophysics Data System (ADS)

Fathipour, V.; Memis, O. G.; Jang, S. J.; Khalid, F.; Brown, R. L.; Hassaninia, I.; Gelfand, R.; Mohseni, H.

2013-09-01

Our group has designed and developed a new SWIR single photon detector called the nano-injection detector that is conceptually designed with biological inspirations taken from the rod cells in human eye. The detector couples a nanoscale sensory region with a large absorption volume to provide avalanche free internal amplification while operating at linear regime with low bias voltages. The low voltage operation makes the detector to be fully compatible with available CMOS technologies. Because there is no photon reemission, detectors can be formed into high-density single-photon detector arrays. As such, the nano injection detectors are viable candidates for SPD and imaging at the short-wave infrared band. Our measurements in 2007 proved a high SNR and a stable excess noise factor of near unity. We are reporting on a high speed version of the detector with 4 orders of magnitude enhancement in speed as well as 2 orders of magnitude reduction in dark current (30nA vs. 10 uA at 1.5V).

Bio-inspired heterogeneous composites for broadband vibration mitigation.

PubMed

Chen, Yanyu; Wang, Lifeng

2015-12-08

Structural biological materials have developed heterogeneous and hierarchical architectures that are responsible for the outstanding performance to provide protection against environmental threats including static and dynamic loading. Inspired by this observation, this research aims to develop new material and structural concepts for broadband vibration mitigation. The proposed composite materials possess a two-layered heterogeneous architecture where both layers consist of high-volume platelet-shape reinforcements and low-volume matrix, similar to the well-known "brick and mortar" microstructure of biological composites. Using finite element method, we numerically demonstrated that broadband wave attenuation zones can be achieved by tailoring the geometric features of the heterogeneous architecture. We reveal that the resulting broadband attenuation zones are gained by directly superimposing the attenuation zones in each constituent layer. This mechanism is further confirmed by the investigation into the phonon dispersion relation of each layer. Importantly, the broadband wave attenuation capability will be maintained when the mineral platelet orientation is locally manipulated, yet a contrast between the mineral platelet concentrations of the two constituent layers is essential. The findings of this work will provide new opportunities to design heterogeneous composites for broadband vibration mitigation and impact resistance under mechanically challenging environmental conditions.

Colloidal-based additive manufacturing of bio-inspired composites

NASA Astrophysics Data System (ADS)

Studart, Andre R.

Composite materials in nature exhibit heterogeneous architectures that are tuned to fulfill the functional demands of the surrounding environment. Examples range from the cellulose-based organic structure of plants to highly mineralized collagen-based skeletal parts like bone and teeth. Because they are often utilized to combine opposing properties such as strength and low-density or stiffness and wear resistance, the heterogeneous architecture of natural materials can potentially address several of the technical limitations of artificial homogeneous composites. However, current man-made manufacturing technologies do not allow for the level of composition and fiber orientation control found in natural heterogeneous systems. In this talk, I will present two additive manufacturing technologies recently developed in our group to build composites with exquisite architectures only rivaled by structures made by living organisms in nature. Since the proposed techniques utilize colloidal suspensions as feedstock, understanding the physics underlying the stability, assembly and rheology of the printing inks is key to predict and control the architecture of manufactured parts. Our results will show that additive manufacturing routes offer a new exciting pathway for the fabrication of biologically-inspired composite materials with unprecedented architectures and functionalities.

Bio-inspired heterogeneous composites for broadband vibration mitigation

NASA Astrophysics Data System (ADS)

Chen, Yanyu; Wang, Lifeng

2015-12-01

Structural biological materials have developed heterogeneous and hierarchical architectures that are responsible for the outstanding performance to provide protection against environmental threats including static and dynamic loading. Inspired by this observation, this research aims to develop new material and structural concepts for broadband vibration mitigation. The proposed composite materials possess a two-layered heterogeneous architecture where both layers consist of high-volume platelet-shape reinforcements and low-volume matrix, similar to the well-known “brick and mortar” microstructure of biological composites. Using finite element method, we numerically demonstrated that broadband wave attenuation zones can be achieved by tailoring the geometric features of the heterogeneous architecture. We reveal that the resulting broadband attenuation zones are gained by directly superimposing the attenuation zones in each constituent layer. This mechanism is further confirmed by the investigation into the phonon dispersion relation of each layer. Importantly, the broadband wave attenuation capability will be maintained when the mineral platelet orientation is locally manipulated, yet a contrast between the mineral platelet concentrations of the two constituent layers is essential. The findings of this work will provide new opportunities to design heterogeneous composites for broadband vibration mitigation and impact resistance under mechanically challenging environmental conditions.

Development of Rapid Diagnostic Kit for Identification of Hanwoo (Korean Native Cattle) Brand Meat by Detecting BIO-TAG

PubMed Central

Park, Sung Kwon; Lee, Myung Hoon; Cho, Soo Hyun

2014-01-01

This study was performed to develop a rapid immuno-assay kit, by using a specific antigen to detect Hanwoo brand meat. We selected a synthetic antigen specific to our target antibody, named BIO-TAG (Tyr-D-Ala-Phe), by utilizing a computer-based analysis and literature review. BIO-TAG tagged with adjuvant was subcutaneously injected in sheep and Hanwoo. The serum and meat juice of the immunized or non-immunized animal were then analyzed, to measure the titer of antibody by ELISA and Western blot. The amount of antibodies against the BIO-TAG increased (p<0.05) in serum by vaccination. Furthermore, meat juice from the immunized Hanwoo showed greater (p<0.05) antibody titer, compared with those from non-immunized groups. To optimze the dilution factor, we performed dot-ELISA, with various combination levels of BIO-TAG. Results from dot-ELISA showed that 2 mg/mL BIO-TAG was sufficient to distinguish the immunized meat from non-immunized groups. These results support our hypothesis that simple immunization of Hanwoo generates a sufficient amount of antibodies to be detectable in the meat juice by means of the immune-assay. Therefore, specific Hanwoo brand meat can be more precisely identified by our rapid diagnostic kit. This technology can deter possible fraud of counterfeit meat brands in the Korean domestic market with ease and rapidity; and offers a new tool that guarantees consumers high quality Hanwoo brand beef. PMID:26761175

LINEBACkER: Bio-inspired Data Reduction Toward Real Time Network Traffic Analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Teuton, Jeremy R.; Peterson, Elena S.; Nordwall, Douglas J.

Abstract—One essential component of resilient cyber applications is the ability to detect adversaries and protect systems with the same flexibility adversaries will use to achieve their goals. Current detection techniques do not enable this degree of flexibility because most existing applications are built using exact or regular-expression matching to libraries of rule sets. Further, network traffic defies traditional cyber security approaches that focus on limiting access based on the use of passwords and examination of lists of installed or downloaded programs. These approaches do not readily apply to network traffic occurring beyond the access control point, and when the datamore » in question are combined control and payload data of ever increasing speed and volume. Manual analysis of network traffic is not normally possible because of the magnitude of the data that is being exchanged and the length of time that this analysis takes. At the same time, using an exact matching scheme to identify malicious traffic in real time often fails because the lists against which such searches must operate grow too large. In this work, we introduce an alternative method for cyber network detection based on similarity-measuring algorithms for gene sequence analysis. These methods are ideal because they were designed to identify similar but nonidentical sequences. We demonstrate that our method is generally applicable to the problem of network traffic analysis by illustrating its use in two different areas both based on different attributes of network traffic. Our approach provides a logical framework for organizing large collections of network data, prioritizing traffic of interest to human analysts, and makes it possible to discover traffic signatures without the bias introduced by expert-directed signature generation. Pattern recognition on reduced representations of network traffic offers a fast, efficient, and more robust way to detect anomalies.« less

[Particle emission characteristics of diesel bus fueled with bio-diesel].

PubMed

Lou, Di-Ming; Chen, Feng; Hu, Zhi-Yuan; Tan, Pi-Qiang; Hu, Wei

2013-10-01

With the use of the Engine Exhaust Particle Sizer (EEPS), a study on the characteristics of particle emissions was carried out on a China-IV diesel bus fueled with blends of 5% , 10% , 20% , 50% bio-diesel transformed from restaurant waste oil and China-IV diesel (marked separately by BD5, BD10, BD20, BD50), pure bio-diesel (BD100) and pure diesel (BD0). The results indicated that particulate number (PN) and mass (PM) emissions of bio-diesel blends increased with the increase in bus speed and acceleration; with increasing bio-diesel content, particulate emissions displayed a relevant declining trend. In different speed ranges, the size distribution of particulate number emissions (PNSD) was bimodal; in different acceleration ranges, PNSD showed a gradual transition from bimodal shape to unimodal when bus operation was switched from decelerating to accelerating status. Bio-diesel blends with higher mixture ratios showed significant reduction in PN emissions for accumulated modes, and the particulate number emission peaks moved towards smaller sizes; but little change was obtained in PN emissions for nuclei modes; reduction also occurred in particle geometric diameter (Dg).

Interconversion of CO2 and formic acid by bio-inspired Ir complexes with pendent bases.

PubMed

Fujita, Etsuko; Muckerman, James T; Himeda, Yuichiro

2013-01-01

Recent investigations of the interconversion of CO2 and formic acid using Ru, Ir and Fe complexes are summarized in this review. During the past several years, both the reaction rates and catalyst stabilities have been significantly improved. Remarkably, the interconversion (i.e., reversibility) has also been achieved under mild conditions in environmentally benign water solvent by slightly changing the pH of the aqueous solution. Only a few catalysts seem to reflect a bio-inspired design such as the use of proton responsive ligands, ligands with pendent bases or acids for a second-coordination-sphere interaction, electroresponsive ligands, and/or ligands having a hydrogen bonding function with a solvent molecule or an added reagent. The most successful of these is an iridium dinuclear complex catalyst that at least has the first three of these characteristics associated with its bridging ligand. By utilizing an acid/base equilibrium for proton removal, the ligand becomes a strong electron donor, resulting in Ir(I) character with a vacant coordination site at each metal center in slightly basic solution. Complemented by DFT calculations, kinetic studies of the rates of formate production using a related family of Ir complexes with and without such functions on the ligand reveal that the rate-determining step for the CO2 hydrogenation is likely to be H2 addition through heterolytic cleavage involving a "proton relay" through the pendent base. The dehydrogenation of formic acid, owing to the proton responsive ligands changing character under slightly acidic pH conditions, is likely to occur by a mechanism with a different rate-determining step. This article is part of a Special Issue entitled: Metals in Bioenergetics and Biomimetics Systems. Copyright © 2012 Elsevier B.V. All rights reserved.

Bio-inspired detoxification using 3D-printed hydrogel nanocomposites

PubMed Central

Gou, Maling; Qu, Xin; Zhu, Wei; Xiang, Mingli; Yang, Jun; Zhang, Kang; Wei, Yuquan; Chen, Shaochen

2014-01-01

Rationally designed nanoparticles that can bind toxins show great promise for detoxification. However, the conventional intravenous administration of nanoparticles for detoxification often leads to nanoparticle accumulation in the liver, posing a risk of secondary poisoning especially in liver-failure patients. Here we present a liver-inspired three-dimensional (3D) detoxification device. This device is created by 3D printing of designer hydrogels with functional polydiacetylene nanoparticles installed in the hydrogel matrix. The nanoparticles can attract, capture and sense toxins, while the 3D matrix with a modified liver lobule microstructure allows toxins to be trapped efficiently. Our results show that the toxin solution completely loses its virulence after treatment using this biomimetic detoxification device. This work provides a proof-of-concept of detoxification by a 3D-printed biomimetic nanocomposite construct in hydrogel, and could lead to the development of alternative detoxification platforms. PMID:24805923

Bio-inspired detoxification using 3D-printed hydrogel nanocomposites

NASA Astrophysics Data System (ADS)

Gou, Maling; Qu, Xin; Zhu, Wei; Xiang, Mingli; Yang, Jun; Zhang, Kang; Wei, Yuquan; Chen, Shaochen

2014-05-01

Rationally designed nanoparticles that can bind toxins show great promise for detoxification. However, the conventional intravenous administration of nanoparticles for detoxification often leads to nanoparticle accumulation in the liver, posing a risk of secondary poisoning especially in liver-failure patients. Here we present a liver-inspired three-dimensional (3D) detoxification device. This device is created by 3D printing of designer hydrogels with functional polydiacetylene nanoparticles installed in the hydrogel matrix. The nanoparticles can attract, capture and sense toxins, while the 3D matrix with a modified liver lobule microstructure allows toxins to be trapped efficiently. Our results show that the toxin solution completely loses its virulence after treatment using this biomimetic detoxification device. This work provides a proof-of-concept of detoxification by a 3D-printed biomimetic nanocomposite construct in hydrogel, and could lead to the development of alternative detoxification platforms.

Bio-inspired detoxification using 3D-printed hydrogel nanocomposites.

PubMed

Gou, Maling; Qu, Xin; Zhu, Wei; Xiang, Mingli; Yang, Jun; Zhang, Kang; Wei, Yuquan; Chen, Shaochen

2014-05-08

Rationally designed nanoparticles that can bind toxins show great promise for detoxification. However, the conventional intravenous administration of nanoparticles for detoxification often leads to nanoparticle accumulation in the liver, posing a risk of secondary poisoning especially in liver-failure patients. Here we present a liver-inspired three-dimensional (3D) detoxification device. This device is created by 3D printing of designer hydrogels with functional polydiacetylene nanoparticles installed in the hydrogel matrix. The nanoparticles can attract, capture and sense toxins, while the 3D matrix with a modified liver lobule microstructure allows toxins to be trapped efficiently. Our results show that the toxin solution completely loses its virulence after treatment using this biomimetic detoxification device. This work provides a proof-of-concept of detoxification by a 3D-printed biomimetic nanocomposite construct in hydrogel, and could lead to the development of alternative detoxification platforms.

INSPIRE and SPIRES Log File Analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Adams, Cole; /Wheaton Coll. /SLAC

2012-08-31

SPIRES, an aging high-energy physics publication data base, is in the process of being replaced by INSPIRE. In order to ease the transition from SPIRES to INSPIRE it is important to understand user behavior and the drivers for adoption. The goal of this project was to address some questions in regards to the presumed two-thirds of the users still using SPIRES. These questions are answered through analysis of the log files from both websites. A series of scripts were developed to collect and interpret the data contained in the log files. The common search patterns and usage comparisons are mademore » between INSPIRE and SPIRES, and a method for detecting user frustration is presented. The analysis reveals a more even split than originally thought as well as the expected trend of user transition to INSPIRE.« less

Development of a Laminar Flame Test Facility for Bio-Diesel Characterization

NASA Astrophysics Data System (ADS)

Tan, Giam

2009-11-01

The relevance of applying testing standards established for diesel fuels to evaluate bio-diesel fuels motivates the design and fabrication of a vertical combustion chamber to be able to measure flame speeds of the varying strains of bio-diesel fuels and to attain more detailed kinetics information for biodiesel fuel. Extensive research is ongoing to understand the impact of fundamental combustion properties such as ignition characteristics, laminar flame speed, strain sensitivity and extinction strain rates on emission and stability characteristics of the combustor. It is envisioned that further flame studies will provide key kinetics validation data for biodiesel-like molecules -- the current test rig was developed with provisions for optical access and for future spectroscopic measurements. The current work focuses on laminar flame speeds since this important parameter contains fundamental information regarding reactivity, diffusivity, and exothermicity of the fuel mixture. It has a significant impact upon the propensity of a flame to flashback and blowoff and also serves as a key scaling parameter for other important combustion characteristics, such as the turbulent flame structure, turbulent flame speed and flame's spatial distribution etc. The flame experiments are challenging as the tested bio-fuel must be uniformly atomized and uniformly dispersed.

Bio-microfluidics: biomaterials and biomimetic designs.

PubMed

Domachuk, Peter; Tsioris, Konstantinos; Omenetto, Fiorenzo G; Kaplan, David L

2010-01-12

Bio-microfluidics applies biomaterials and biologically inspired structural designs (biomimetics) to microfluidic devices. Microfluidics, the techniques for constraining fluids on the micrometer and sub-micrometer scale, offer applications ranging from lab-on-a-chip to optofluidics. Despite this wealth of applications, the design of typical microfluidic devices imparts relatively simple, laminar behavior on fluids and is realized using materials and techniques from silicon planar fabrication. On the other hand, highly complex microfluidic behavior is commonplace in nature, where fluids with nonlinear rheology flow through chaotic vasculature composed from a range of biopolymers. In this Review, the current state of bio-microfluidic materials, designs and applications are examined. Biopolymers enable bio-microfluidic devices with versatile functionalization chemistries, flexibility in fabrication, and biocompatibility in vitro and in vivo. Polymeric materials such as alginate, collagen, chitosan, and silk are being explored as bulk and film materials for bio-microfluidics. Hydrogels offer options for mechanically functional devices for microfluidic systems such as self-regulating valves, microlens arrays and drug release systems, vital for integrated bio-microfluidic devices. These devices including growth factor gradients to study cell responses, blood analysis, biomimetic capillary designs, and blood vessel tissue culture systems, as some recent examples of inroads in the field that should lead the way in a new generation of microfluidic devices for bio-related needs and applications. Perhaps one of the most intriguing directions for the future will be fully implantable microfluidic devices that will also integrate with existing vasculature and slowly degrade to fully recapitulate native tissue structure and function, yet serve critical interim functions, such as tissue maintenance, drug release, mechanical support, and cell delivery.

Bio-Inspired Multi-Functional Drug Transport Design Concept and Simulations †

PubMed Central

Pidaparti, Ramana M.; Cartin, Charles; Su, Guoguang

2017-01-01

In this study, we developed a microdevice concept for drug/fluidic transport taking an inspiration from supramolecular motor found in biological cells. Specifically, idealized multi-functional design geometry (nozzle/diffuser/nozzle) was developed for (i) fluidic/particle transport; (ii) particle separation; and (iii) droplet generation. Several design simulations were conducted to demonstrate the working principles of the multi-functional device. The design simulations illustrate that the proposed design concept is feasible for multi-functionality. However, further experimentation and optimization studies are needed to fully evaluate the multifunctional device concept for multiple applications. PMID:28952516

Fluorescence bio-barcode DNA assay based on gold and magnetic nanoparticles for detection of Exotoxin A gene sequence.

PubMed

Amini, Bahram; Kamali, Mehdi; Salouti, Mojtaba; Yaghmaei, Parichehreh

2017-06-15

Bio-barcode DNA based on gold nanoparticle (bDNA-GNPs) as a new generation of biosensor based detection tools, holds promise for biological science studies. They are of enormous importance in the emergence of rapid and sensitive procedures for detecting toxins of microorganisms. Exotoxin A (ETA) is the most toxic virulence factor of Pseudomonas aeruginosa. ETA has ADP-ribosylation activity and decisively affects the protein synthesis of the host cells. In the present study, we developed a fluorescence bio-barcode technology to trace P. aeruginosa ETA. The GNPs were coated with the first target-specific DNA probe 1 (1pDNA) and bio-barcode DNA, which acted as a signal reporter. The magnetic nanoparticles (MNPs) were coated with the second target-specific DNA probe 2 (2pDNA) that was able to recognize the other end of the target DNA. After binding the nanoparticles with the target DNA, the following sandwich structure was formed: MNP 2pDNA/tDNA/1pDNA-GNP-bDNA. After isolating the sandwiches by a magnetic field, the DNAs of the probes which have been hybridized to their complementary DNA, GNPs and MNPs, via the hydrogen, electrostatic and covalently bonds, were released from the sandwiches after dissolving in dithiothreitol solution (DTT 0.8M). This bio-barcode DNA with known DNA sequence was then detected by fluorescence spectrophotometry. The findings showed that the new method has the advantages of fast, high sensitivity (the detection limit was 1.2ng/ml), good selectivity, and wide linear range of 5-200ng/ml. The regression analysis also showed that there was a good linear relationship (∆F=0.57 [target DNA]+21.31, R 2 =0.9984) between the fluorescent intensity and the target DNA concentration in the samples. Copyright © 2016. Published by Elsevier B.V.

Nanozyme-based bio-barcode assay for high sensitive and logic-controlled specific detection of multiple DNAs.

PubMed

Lin, Xiaodong; Liu, Yaqing; Tao, Zhanhui; Gao, Jinting; Deng, Jiankang; Yin, Jinjin; Wang, Shuo

2017-08-15

Since HCV and HIV share a common transmission path, high sensitive detection of HIV and HCV gene is of significant importance to improve diagnosis accuracy and cure rate at early stage for HIV virus-infected patients. In our investigation, a novel nanozyme-based bio-barcode fluorescence amplified assay is successfully developed for simultaneous detection of HIV and HCV DNAs with excellent sensitivity in an enzyme-free and label-free condition. Here, bimetallic nanoparticles, PtAu NPs , present outstanding peroxidase-like activity and act as barcode to catalyze oxidation of nonfluorescent substrate of amplex red (AR) into fluorescent resorufin generating stable and sensitive "Turn On" fluorescent output signal, which is for the first time to be integrated with bio-barcode strategy for fluorescence detection DNA. Furthermore, the provided strategy presents excellent specificity and can distinguish single-base mismatched mutant from target DNA. What interesting is that cascaded INHIBIT-OR logic gate is integrated with biosensors for the first time to distinguish individual target DNA from each other under logic function control, which presents great application in development of rapid and intelligent detection. Copyright © 2017. Published by Elsevier B.V.

Novel locomotion via biological inspiration

NASA Astrophysics Data System (ADS)

Quinn, Roger D.; Boxerbaum, Alexander; Palmer, Luther; Chiel, Hillel; Diller, Eric; Hunt, Alexander; Bachmann, Richard

2011-05-01

Animal behavioral, physiological and neurobiological studies are providing a wealth of inspirational data for robot design and control. Several very different biologically inspired mobile robots will be reviewed. A robot called DIGbot is being developed that moves independent of the direction of gravity using Distributed Inward Gripping (DIG) as a rapid and robust attachment mechanism observed in climbing animals. DIGbot is an 18 degree of freedom hexapod with onboard power and control systems. Passive compliance in its feet, which is inspired by the flexible tarsus of the cockroach, increases the robustness of the adhesion strategy and enables DIGbot to execute large steps and stationary turns while walking on mesh screens. A Whegs™ robot, inspired by insect locomotion principles, is being developed that can be rapidly reconfigured between tracks and wheel-legs and carry GeoSystems Zipper Mast. The mechanisms that cause it to passively change its gait on irregular terrain have been integrated into its hubs for a compact and modular design. The robot is designed to move smoothly on moderately rugged terrain using its tracks and run on irregular terrain and stairs using its wheel-legs. We are also developing soft bodied robots that use peristalsis, the same method of locomotion earthworms use. We present a technique of using a braided mesh exterior to produce fluid waves of motion along the body of the robot that increase the robot's speed relative to previous designs. The concept is highly scalable, for endoscopes to water, oil or gas line inspection.

NASA's Bio-Inspired Acoustic Absorber Concept

NASA Technical Reports Server (NTRS)

Koch, L. Danielle

2017-01-01

are encouraged to contact the NASA Glenn Technology Transfer Office, https:technology.grc.nasa.gov. The NASA Glenn Office of Education https:www.nasa.govcentersglenneducationindex.html and the NASA Glenn Virtual Interchange for Nature-Inspired Exploration https:www.grc.nasa.govvine are also helping to make research like this accessible to the public and students of all ages.

Negated bio-events: analysis and identification

PubMed Central

2013-01-01

Background Negation occurs frequently in scientific literature, especially in biomedical literature. It has previously been reported that around 13% of sentences found in biomedical research articles contain negation. Historically, the main motivation for identifying negated events has been to ensure their exclusion from lists of extracted interactions. However, recently, there has been a growing interest in negative results, which has resulted in negation detection being identified as a key challenge in biomedical relation extraction. In this article, we focus on the problem of identifying negated bio-events, given gold standard event annotations. Results We have conducted a detailed analysis of three open access bio-event corpora containing negation information (i.e., GENIA Event, BioInfer and BioNLP’09 ST), and have identified the main types of negated bio-events. We have analysed the key aspects of a machine learning solution to the problem of detecting negated events, including selection of negation cues, feature engineering and the choice of learning algorithm. Combining the best solutions for each aspect of the problem, we propose a novel framework for the identification of negated bio-events. We have evaluated our system on each of the three open access corpora mentioned above. The performance of the system significantly surpasses the best results previously reported on the BioNLP’09 ST corpus, and achieves even better results on the GENIA Event and BioInfer corpora, both of which contain more varied and complex events. Conclusions Recently, in the field of biomedical text mining, the development and enhancement of event-based systems has received significant interest. The ability to identify negated events is a key performance element for these systems. We have conducted the first detailed study on the analysis and identification of negated bio-events. Our proposed framework can be integrated with state-of-the-art event extraction systems. The

Nanoporous Block Polymer Thin Films Functionalized with Bio-Inspired Ligands for the Efficient Capture of Heavy Metal Ions from Water.

PubMed

Weidman, Jacob L; Mulvenna, Ryan A; Boudouris, Bryan W; Phillip, William A

2017-06-07

Heavy metal contamination of water supplies poses a serious threat to public health, prompting the development of novel and sustainable treatment technologies. One promising approach is to molecularly engineer the chemical affinity of a material for the targeted removal of specific molecules from solution. In this work, nanoporous polymer thin films generated from tailor-made block polymers were functionalized with the bio-inspired moieties glutathione and cysteamine for the removal of heavy metal ions, including lead and cadmium, from aqueous solutions. In a single equilibrium stage, the films achieved removal rates of the ions in excess of 95%, which was consistent with predictions based on the engineered material properties. In a flow-through configuration, the thin films achieved an even greater removal rate of the metal ions. Furthermore, in mixed ion solutions the capacity of the thin films, and corresponding removal rates, did not demonstrate any reduction due to competitive adsorption effects. After such experiments the material was repeatedly regenerated quickly with no observed loss in capacity. Thus, these membranes provide a sustainable platform for the efficient purification of lead- and cadmium-contaminated water sources to safe levels. Moreover, their straightforward chemical modifications suggest that they could be engineered to treat sources containing other recalcitrant environmental contaminants as well.

Automated High-Speed Video Detection of Small-Scale Explosives Testing

NASA Astrophysics Data System (ADS)

Ford, Robert; Guymon, Clint

2013-06-01

Small-scale explosives sensitivity test data is used to evaluate hazards of processing, handling, transportation, and storage of energetic materials. Accurate test data is critical to implementation of engineering and administrative controls for personnel safety and asset protection. Operator mischaracterization of reactions during testing contributes to either excessive or inadequate safety protocols. Use of equipment and associated algorithms to aid the operator in reaction determination can significantly reduce operator error. Safety Management Services, Inc. has developed an algorithm to evaluate high-speed video images of sparks from an ESD (Electrostatic Discharge) machine to automatically determine whether or not a reaction has taken place. The algorithm with the high-speed camera is termed GoDetect (patent pending). An operator assisted version for friction and impact testing has also been developed where software is used to quickly process and store video of sensitivity testing. We have used this method for sensitivity testing with multiple pieces of equipment. We present the fundamentals of GoDetect and compare it to other methods used for reaction detection.

Profile parameters of wheelset detection for high speed freight train

NASA Astrophysics Data System (ADS)

Yang, Kai; Ma, Li; Gao, Xiaorong; Wang, Li

2012-04-01

Because of freight train, in China, transports goods on railway freight line throughout the country, it does not depart from or return to engine shed during a long phase, thus we cannot monitor the quality of wheel set effectively. This paper provides a system which uses leaser and high speed camera, applies no-contact light section technology to get precise wheel set profile parameters. The paper employs clamping-track method to avoid complex railway ballast modification project. And detailed descript an improved image-tracking algorithm to extract central line from profile curve. For getting one pixel width and continuous line of the profile curve, uses local gray maximum points as direction control points to direct tracking direction. The results based on practical experiment show the system adapted to detection environment of high speed and high vibration, and it can effectively detect the wheelset geometric parameters with high accuracy. The system fills the gaps in wheel set detection for freight train in main line and has an enlightening function on monitoring the quality of wheel set.

Mimosa-inspired design of a flexible pressure sensor with touch sensitivity.

PubMed

Su, Bin; Gong, Shu; Ma, Zheng; Yap, Lim Wei; Cheng, Wenlong

2015-04-24

A bio-inspired flexible pressure sensor is generated with high sensitivity (50.17 kPa(-1)), quick responding time (<20 ms), and durable stability (negligible loading-unloading signal changes over 10 000 cycles). Notably, the key resource of surface microstructures upon sensor substrates results from the direct molding of natural mimosa leaves, presenting a simple, environment-friendly and easy scale-up fabrication process for these flexible pressure sensors. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Enhanced Mechanical Performance of Bio-Inspired Hybrid Structures Utilising Topological Interlocking Geometry

PubMed Central

Djumas, Lee; Molotnikov, Andrey; Simon, George P.; Estrin, Yuri

2016-01-01

Structural composites inspired by nacre have emerged as prime exemplars for guiding materials design of fracture-resistant, rigid hybrid materials. The intricate microstructure of nacre, which combines a hard majority phase with a small fraction of a soft phase, achieves superior mechanical properties compared to its constituents and has generated much interest. However, replicating the hierarchical microstructure of nacre is very challenging, not to mention improving it. In this article, we propose to alter the geometry of the hard building blocks by introducing the concept of topological interlocking. This design principle has previously been shown to provide an inherently brittle material with a remarkable flexural compliance. We now demonstrate that by combining the basic architecture of nacre with topological interlocking of discrete hard building blocks, hybrid materials of a new type can be produced. By adding a soft phase at the interfaces between topologically interlocked blocks in a single-build additive manufacturing process, further improvement of mechanical properties is achieved. The design of these fabricated hybrid structures has been guided by computational work elucidating the effect of various geometries. To our knowledge, this is the first reported study that combines the advantages of nacre-inspired structures with the benefits of topological interlocking. PMID:27216277

Enhanced Mechanical Performance of Bio-Inspired Hybrid Structures Utilising Topological Interlocking Geometry.

PubMed

Djumas, Lee; Molotnikov, Andrey; Simon, George P; Estrin, Yuri

2016-05-24

Structural composites inspired by nacre have emerged as prime exemplars for guiding materials design of fracture-resistant, rigid hybrid materials. The intricate microstructure of nacre, which combines a hard majority phase with a small fraction of a soft phase, achieves superior mechanical properties compared to its constituents and has generated much interest. However, replicating the hierarchical microstructure of nacre is very challenging, not to mention improving it. In this article, we propose to alter the geometry of the hard building blocks by introducing the concept of topological interlocking. This design principle has previously been shown to provide an inherently brittle material with a remarkable flexural compliance. We now demonstrate that by combining the basic architecture of nacre with topological interlocking of discrete hard building blocks, hybrid materials of a new type can be produced. By adding a soft phase at the interfaces between topologically interlocked blocks in a single-build additive manufacturing process, further improvement of mechanical properties is achieved. The design of these fabricated hybrid structures has been guided by computational work elucidating the effect of various geometries. To our knowledge, this is the first reported study that combines the advantages of nacre-inspired structures with the benefits of topological interlocking.

Bio-inspired computational design of iron catalysts for the hydrogenation of carbon dioxide.

PubMed

Yang, Xinzheng

2015-08-25

Inspired by the active site structure of monoiron hydrogenase, a series of iron complexes are built using experimentally ready-made acylmethylpyridinol and aliphatic PNP pincer ligands. Density functional theory calculations indicate that the newly designed iron complexes are very promising to catalyze the formation of formic acid from H2 and CO2.

Non-Enzymatic Detection of Bacterial Genomic DNA Using the Bio-Barcode Assay

PubMed Central

Hill, Haley D.; Vega, Rafael A.; Mirkin, Chad A.

2011-01-01

The detection of bacterial genomic DNA through a non-enzymatic nanomaterials based amplification method, the bio-barcode assay, is reported. The assay utilizes oligonucleotide functionalized magnetic microparticles to capture the target of interest from the sample. A critical step in the new assay involves the use of blocking oligonucleotides during heat denaturation of the double stranded DNA. These blockers bind to specific regions of the target DNA upon cooling, and prevent the duplex DNA from re-hybridizing, which allows the particle probes to bind. Following target isolation using the magnetic particles, oligonucleotide functionalized gold nanoparticles act as target recognition agents. The oligonucleotides on the nanoparticle (barcodes) act as amplification surrogates. The barcodes are then detected using the Scanometric method. The limit of detection for this assay was determined to be 2.5 femtomolar, and this is the first demonstration of a barcode type assay for the detection of double stranded, genomic DNA. PMID:17927207

A light-powered bio-capacitor with nanochannel modulation.

PubMed

Rao, Siyuan; Lu, Shanfu; Guo, Zhibin; Li, Yuan; Chen, Deliang; Xiang, Yan

2014-09-03

An artificial bio-capacitor system is established, consisting of the proton-pump protein proteorhodopsin and a modified alumina nanochannel, inspired by the capacitor-like behavior of plasma membranes realized through the cooperation of ion-pump and ion-channel proteins. Capacitor-like features of this simplified system are realized and identified, and the photocurrent duration time can be modulated by nanochannel modification to obtain favorable square-wave currents. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

CROSS-DISCIPLINARY PHYSICS AND RELATED AREAS OF SCIENCE AND TECHNOLOGY: Surface Micromachined Adjustable Micro-Concave Mirror for Bio-Detection Applications

NASA Astrophysics Data System (ADS)

Kuo, Ju-Nan; Chen, Wei-Lun; Jywe, Wen-Yuh

2009-08-01

We present a bio-detection system integrated with an adjustable micro-concave mirror. The bio-detection system consists of an adjustable micro-concave mirror, micro flow cytometer chip and optical detection module. The adjustable micro-concave mirror can be fabricated with ease using commercially available MEMS foundry services (such as multiuser MEMS processes, MUMPs) and its curvature can be controlled utilizing thermal or electrical effects. Experimental results show that focal lengths of the micro-concave mirror ranging from 313.5 to 2275.0 μm are achieved. The adjustable micro-concave mirror can be used to increase the efficiency of optical detection and provide a high signal-to-noise ratio. The developed micro-concave mirror is integrated with a micro flow cytometer for cell counting applications. Successful counting of fluorescent-labeled beads is demonstrated using the developed method.

High throughput detection of antibody self-interaction by bio-layer interferometry.

PubMed

Sun, Tingwan; Reid, Felicia; Liu, Yuqi; Cao, Yuan; Estep, Patricia; Nauman, Claire; Xu, Yingda

2013-01-01

Self-interaction of an antibody may lead to aggregation, low solubility or high viscosity. Rapid identification of highly developable leads remains challenging, even though progress has been made with the introduction of techniques such as self-interaction chromatography (SIC) and cross-interaction chromatography (CIC). Here, we report a high throughput method to detect antibody clone self-interaction (CSI) using bio-layer interferometry (BLI) technology. Antibodies with strong self-interaction responses in the CSI-BLI assay also show delayed retention times in SIC and CIC. This method allows hundreds of candidates to be screened in a matter of hours with minimal material consumption.

Finding NEMO (novel electromaterial muscle oscillator): a polypyrrole powered robotic fish with real-time wireless speed and directional control

NASA Astrophysics Data System (ADS)

McGovern, Scott; Alici, Gursel; Truong, Van-Tan; Spinks, Geoffrey

2009-09-01

This paper presents the development of an autonomously powered and controlled robotic fish that incorporates an active flexural joint tail fin, activated through conducting polymer actuators based on polypyrrole (PPy). The novel electromaterial muscle oscillator (NEMO) tail fin assembly on the fish could be controlled wirelessly in real time by varying the frequency and duty cycle of the voltage signal supplied to the PPy bending-type actuators. Directional control was achieved by altering the duty cycle of the voltage input to the NEMO tail fin, which shifted the axis of oscillation and enabled turning of the robotic fish. At low speeds, the robotic fish had a turning circle as small as 15 cm (or 1.1 body lengths) in radius. The highest speed of the fish robot was estimated to be approximately 33 mm s-1 (or 0.25 body lengths s-1) and was achieved with a flapping frequency of 0.6-0.8 Hz which also corresponded with the most hydrodynamically efficient mode for tail fin operation. This speed is approximately ten times faster than those for any previously reported artificial muscle based device that also offers real-time speed and directional control. This study contributes to previously published studies on bio-inspired functional devices, demonstrating that electroactive polymer actuators can be real alternatives to conventional means of actuation such as electric motors.

Bio-inspired canopies for the reduction of roughness noise

NASA Astrophysics Data System (ADS)

Clark, Ian A.; Daly, Conor A.; Devenport, William; Alexander, W. Nathan; Peake, Nigel; Jaworski, Justin W.; Glegg, Stewart

2016-12-01

This work takes inspiration from the structure of the down covering the flight feathers of larger species of owls, which contributes to their ability to fly almost silently at frequencies above 1.6 kHz. Microscope photographs of the down show that it consists of hairs that form a structure similar to that of a forest. The hairs initially rise almost perpendicular to the feather surface but then bend over in the flow direction to form a canopy with an open area ratio of about 70 percent. Experiments have been performed to examine the noise radiated by a large open area ratio canopy suspended above a surface. The canopy is found to dramatically reduce pressure fluctuations on the underlying surface. While the canopy can produce its own sound, particularly at high frequencies, the reduction in surface pressure fluctuations can reduce the noise scattered from an underlying rough surface at lower frequencies. A theoretical model is developed which characterizes the mechanism of surface pressure reduction as a result of the mixing layer instability of flow over forest canopies.

A new biarticular actuator design facilitates control of leg function in BioBiped3.

PubMed

Sharbafi, Maziar Ahmad; Rode, Christian; Kurowski, Stefan; Scholz, Dorian; Möckel, Rico; Radkhah, Katayon; Zhao, Guoping; Rashty, Aida Mohammadinejad; Stryk, Oskar von; Seyfarth, Andre

2016-07-01

Bioinspired legged locomotion comprises different aspects, such as (i) benefiting from reduced complexity control approaches as observed in humans/animals, (ii) combining embodiment with the controllers and (iii) reflecting neural control mechanisms. One of the most important lessons learned from nature is the significant role of compliance in simplifying control, enhancing energy efficiency and robustness against perturbations for legged locomotion. In this research, we investigate how body morphology in combination with actuator design may facilitate motor control of leg function. Inspired by the human leg muscular system, we show that biarticular muscles have a key role in balancing the upper body, joint coordination and swing leg control. Appropriate adjustment of biarticular spring rest length and stiffness can simplify the control and also reduce energy consumption. In order to test these findings, the BioBiped3 robot was developed as a new version of BioBiped series of biologically inspired, compliant musculoskeletal robots. In this robot, three-segmented legs actuated by mono- and biarticular series elastic actuators mimic the nine major human leg muscle groups. With the new biarticular actuators in BioBiped3, novel simplified control concepts for postural balance and for joint coordination in rebounding movements (drop jumps) were demonstrated and approved.

A bio-inspired design of a hand robotic exoskeleton for rehabilitation

NASA Astrophysics Data System (ADS)

Ong, Aira Patrice R.; Bugtai, Nilo T.

2018-02-01

This paper presents the methodology for the design of a five-degree of freedom wearable robotic exoskeleton for hand rehabilitation. The design is inspired by the biological structure and mechanism of the human hand. One of the distinct features of the device is the cable-driven actuation, which provides the flexion and extension motion. A prototype of the orthotic device has been developed to prove the model of the system and has been tested in a 3D printed mechanical hand. The result showed that the proposed device was consistent with the requirements of bionics and was able to demonstrate the flexion and extension of the system.

Feasibility of shutter-speed DCE-MRI for improved prostate cancer detection.

PubMed

Li, Xin; Priest, Ryan A; Woodward, William J; Tagge, Ian J; Siddiqui, Faisal; Huang, Wei; Rooney, William D; Beer, Tomasz M; Garzotto, Mark G; Springer, Charles S

2013-01-01

The feasibility of shutter-speed model dynamic-contrast-enhanced MRI pharmacokinetic analyses for prostate cancer detection was investigated in a prebiopsy patient cohort. Differences of results from the fast-exchange-regime-allowed (FXR-a) shutter-speed model version and the fast-exchange-limit-constrained (FXL-c) standard model are demonstrated. Although the spatial information is more limited, postdynamic-contrast-enhanced MRI biopsy specimens were also examined. The MRI results were correlated with the biopsy pathology findings. Of all the model parameters, region-of-interest-averaged K(trans) difference [ΔK(trans) ≡ K(trans)(FXR-a) - K(trans)(FXL-c)] or two-dimensional K(trans)(FXR-a) vs. k(ep)(FXR-a) values were found to provide the most useful biomarkers for malignant/benign prostate tissue discrimination (at 100% sensitivity for a population of 13, the specificity is 88%) and disease burden determination. (The best specificity for the fast-exchange-limit-constrained analysis is 63%, with the two-dimensional plot.) K(trans) and k(ep) are each measures of passive transcapillary contrast reagent transfer rate constants. Parameter value increases with shutter-speed model (relative to standard model) analysis are larger in malignant foci than in normal-appearing glandular tissue. Pathology analyses verify the shutter-speed model (FXR-a) promise for prostate cancer detection. Parametric mapping may further improve pharmacokinetic biomarker performance. Copyright © 2012 Wiley Periodicals, Inc.

Product and technology innovation: what can biomimicry inspire?

PubMed

Lurie-Luke, Elena

2014-12-01

Biomimicry (bio- meaning life in Greek, and -mimesis, meaning to copy) is a growing field that seeks to interpolate natural biological mechanisms and structures into a wide range of applications. The rise of interest in biomimicry in recent years has provided a fertile ground for innovation. This review provides an eco-system based analysis of biomimicry inspired technology and product innovation. A multi-disciplinary framework has been developed to accomplish this analysis and the findings focus on the areas that have been most strikingly affected by the application of biomimicry and also highlight the emerging trends and opportunity areas. Copyright © 2014 Elsevier Inc. All rights reserved.

Spider web-inspired acoustic metamaterials

NASA Astrophysics Data System (ADS)

Miniaci, Marco; Krushynska, Anastasiia; Movchan, Alexander B.; Bosia, Federico; Pugno, Nicola M.

2016-08-01

Spider silk is a remarkable example of bio-material with superior mechanical characteristics. Its multilevel structural organization of dragline and viscid silk leads to unusual and tunable properties, extensively studied from a quasi-static point of view. In this study, inspired by the Nephila spider orb web architecture, we propose a design for mechanical metamaterials based on its periodic repetition. We demonstrate that spider-web metamaterial structure plays an important role in the dynamic response and wave attenuation mechanisms. The capability of the resulting structure to inhibit elastic wave propagation in sub-wavelength frequency ranges is assessed, and parametric studies are performed to derive optimal configurations and constituent mechanical properties. The results show promise for the design of innovative lightweight structures for tunable vibration damping and impact protection, or the protection of large scale infrastructure such as suspended bridges.

Single-Molecule Detection in Micron-Sized Capillaries

NASA Astrophysics Data System (ADS)

Ball, David A.; Shen, Guoqing; Davis, Lloyd M.

2004-11-01

The detection of individual molecules in solution by laser-induced fluorescence is becoming an increasingly important tool for biophysics research and biotechnology applications. In a typical single-molecule detection (SMD) experiment, diffusion is the dominant mode of transport of fluorophores through the focused laser beam. In order to more rapidly process a large number of slowly diffusing bio-molecules for applications in pharmaceutical drug discovery, a flow can be introduced within a capillary. If the flow speed is sufficient, bio-molecules will be carried through the probe volume significantly faster than by diffusion alone. Here we discuss SMD near the tip of, and in, such micron-sized capillaries, with a high numerical-aperture microscope objective used for confocal-epi-illumination along the axis of the capillary. Problems such as molecular adsorption to the glass are also addressed.

Les nanostructures pour créer de la couleur, un art inspiré par la nature

NASA Astrophysics Data System (ADS)

Ball, Philip

2018-02-01

Les reflets changeants des plumes de la queue du paon ont captivé plus d'un esprit curieux. Le scientifique anglais Robert Hooke les qualifiait en 1665 de « surnaturelles » en constatant que, mouillées, elles perdaient leurs couleurs. À l'aide du microscope inventé depuis peu, il observa ces plumes, et découvrit qu'elles étaient couvertes de stries - qu'il suspecta d'être à l'origine des couleurs. Aujourd'hui, la recherche tente de s'inspirer de ces phénomènes : des applications « bio-inspirées » sont en voie de concrétisation. ARRAY(0x29ad218)

A new numerical approach to solve Thomas-Fermi model of an atom using bio-inspired heuristics integrated with sequential quadratic programming.

PubMed

Raja, Muhammad Asif Zahoor; Zameer, Aneela; Khan, Aziz Ullah; Wazwaz, Abdul Majid

2016-01-01

In this study, a novel bio-inspired computing approach is developed to analyze the dynamics of nonlinear singular Thomas-Fermi equation (TFE) arising in potential and charge density models of an atom by exploiting the strength of finite difference scheme (FDS) for discretization and optimization through genetic algorithms (GAs) hybrid with sequential quadratic programming. The FDS procedures are used to transform the TFE differential equations into a system of nonlinear equations. A fitness function is constructed based on the residual error of constituent equations in the mean square sense and is formulated as the minimization problem. Optimization of parameters for the system is carried out with GAs, used as a tool for viable global search integrated with SQP algorithm for rapid refinement of the results. The design scheme is applied to solve TFE for five different scenarios by taking various step sizes and different input intervals. Comparison of the proposed results with the state of the art numerical and analytical solutions reveals that the worth of our scheme in terms of accuracy and convergence. The reliability and effectiveness of the proposed scheme are validated through consistently getting optimal values of statistical performance indices calculated for a sufficiently large number of independent runs to establish its significance.

Writing Inspired

ERIC Educational Resources Information Center

Tischhauser, Karen

2015-01-01

Students need inspiration to write. Assigning is not teaching. In order to inspire students to write fiction worth reading, teachers must take them through the process of writing. Physical objects inspire good writing with depth. In this article, the reader will be taken through the process of inspiring young writers through the use of boxes.…

Natural Inspired Intelligent Visual Computing and Its Application to Viticulture.

PubMed

Ang, Li Minn; Seng, Kah Phooi; Ge, Feng Lu

2017-05-23

This paper presents an investigation of natural inspired intelligent computing and its corresponding application towards visual information processing systems for viticulture. The paper has three contributions: (1) a review of visual information processing applications for viticulture; (2) the development of natural inspired computing algorithms based on artificial immune system (AIS) techniques for grape berry detection; and (3) the application of the developed algorithms towards real-world grape berry images captured in natural conditions from vineyards in Australia. The AIS algorithms in (2) were developed based on a nature-inspired clonal selection algorithm (CSA) which is able to detect the arcs in the berry images with precision, based on a fitness model. The arcs detected are then extended to perform the multiple arcs and ring detectors information processing for the berry detection application. The performance of the developed algorithms were compared with traditional image processing algorithms like the circular Hough transform (CHT) and other well-known circle detection methods. The proposed AIS approach gave a Fscore of 0.71 compared with Fscores of 0.28 and 0.30 for the CHT and a parameter-free circle detection technique (RPCD) respectively.

Two types of nanoparticle-based bio-barcode amplification assays to detect HIV-1 p24 antigen.

PubMed

Dong, Huahuang; Liu, Jianli; Zhu, Hong; Ou, Chin-Yih; Xing, Wenge; Qiu, Maofeng; Zhang, Guiyun; Xiao, Yao; Yao, Jun; Pan, Pinliang; Jiang, Yan

2012-08-31

HIV-1 p24 antigen is a major viral component of human immunodeficiency virus type 1 (HIV-1) which can be used to identify persons in the early stage of infection and transmission of HIV-1 from infected mothers to infants. The detection of p24 is usually accomplished by using an enzyme-linked immunosorbent assay (ELISA) with low detection sensitivity. Here we report the use of two bio-barcode amplification (BCA) assays combined with polymerase chain reaction (PCR) and gel electrophoresis to quantify HIV-1 p24 antigen. A pair of anti-p24 monoclonal antibodies (mAbs) were used in BCA assays to capture HIV-1 p24 antigen in a sandwich format and allowed for the quantitative measurement of captured p24 using PCR and gel electrophoresis. The first 1 G12 mAb was coated on microplate wells or magnetic microparticles (MMPs) to capture free p24 antigens. Captured p24 in turn captured 1D4 mAb coated gold nanoparticle probes (GNPs) containing double-stranded DNA oligonucleotides. One strand of the oligonucleotides was covalently immobilized whereas the unbound complimentary bio-barcode DNA strand could be released upon heating. The released bio-barcode DNA was amplified by PCR, electrophoresed in agarose gel and quantified. The in-house ELISA assay was found to quantify p24 antigen with a limit of detection (LOD) of 1,000 pg/ml and a linear range between 3,000 and 100,000 pg/ml. In contrast, the BCA-based microplate method yielded an LOD of 1 pg/ml and a linear detection range from 1 to 10,000 pg/ml. The BCA-based MMP method yielded an LOD of 0.1 pg/ml and a linear detection range from 0.1 to 1,000 pg/ml. When combined with PCR and simple gel electrophoresis, BCA-based microplate and MMPs assays can be used to quantify HIV-1 p24 antigen. These methods are 3-4 orders of magnitude more sensitive than our in-house ELISA-based assay and may provide a useful approach to detect p24 in patients newly infected with HIV.

Algal antifouling and fouling-release properties of metal surfaces coated with a polymer inspired by marine mussels.

PubMed

Statz, Andrea; Finlay, John; Dalsin, Jeffrey; Callow, Maureen; Callow, James A; Messersmith, Phillip B

2006-01-01

The marine antifouling and fouling-release performance of titanium surfaces coated with a bio-inspired polymer was investigated. The polymer consisted of methoxy-terminated poly(ethylene glycol) (mPEG) conjugated to the adhesive amino acid l-3,4-dihydroxyphenylalanine (DOPA) and was chosen based on its successful resistance to protein and mammalian cell fouling. Biofouling assays for the settlement and release of the diatom Navicula perminuta and settlement, growth and release of zoospores and sporelings (young plants) of the green alga Ulva linza were carried out. Results were compared to glass, a poly(dimethylsiloxane) elastomer (Silastic T2) and uncoated Ti. The mPEG-DOPA3 modified Ti surfaces exhibited a substantial decrease in attachment of both cells of N. perminuta and zoospores of U. linza as well as the highest detachment of attached cells under flow compared to control surfaces. The superior performance of this polymer over a standard silicone fouling-release coating in diatom assays and approximately equivalent performance in zoospore assays suggests that this bio-inspired polymer may be effective in marine antifouling and fouling-release applications.

Evaluation of the bioNexia Legionella Test, Including Impact of Incubation Time Extension, for Detection of Legionella pneumophila Serogroup 1 Antigen in Urine.

PubMed

Badoux, Paul; Euser, Sjoerd M; Bruin, Jacob P; Mulder, Patrick P G; Yzerman, Ed P F

2017-06-01

In this study, we compared the bioNexia test (bioMérieux, Marcy-l'Étoile, France), a new immunochromatographic assay for the detection of Legionella pneumophila serogroup 1 in urine, with the BinaxNOW urinary antigen test (Alere, Waltham, Massachusetts, USA). After 15 min of incubation (in accordance with the manufacturers' instructions), the sensitivities and specificities were, respectively, 76.5% and 97.2% for the bioNexia test and 87.1% and 100% for the BinaxNOW test. After a prolonged incubation time of 60 min, the sensitivities and specificities increased to, respectively, 89.4% and 97.2% for the bioNexia test and 91.8% and 100% for the BinaxNOW test. When the tests were read after 15 min, the concentration of discrepant urine samples increased the sensitivities to 94.1% for both tests. In conclusion, we found that although the bioNexia test showed lower sensitivity for the detection of L. pneumophila antigen in nonconcentrated urine compared to the BinaxNOW test, a prolonged incubation time as well as the use of concentrated samples showed comparable sensitivities for both tests. Copyright © 2017 American Society for Microbiology.

High-Speed Edge-Detecting Line Scan Smart Camera

NASA Technical Reports Server (NTRS)

Prokop, Norman F.

2012-01-01

A high-speed edge-detecting line scan smart camera was developed. The camera is designed to operate as a component in a NASA Glenn Research Center developed inlet shock detection system. The inlet shock is detected by projecting a laser sheet through the airflow. The shock within the airflow is the densest part and refracts the laser sheet the most in its vicinity, leaving a dark spot or shadowgraph. These spots show up as a dip or negative peak within the pixel intensity profile of an image of the projected laser sheet. The smart camera acquires and processes in real-time the linear image containing the shock shadowgraph and outputting the shock location. Previously a high-speed camera and personal computer would perform the image capture and processing to determine the shock location. This innovation consists of a linear image sensor, analog signal processing circuit, and a digital circuit that provides a numerical digital output of the shock or negative edge location. The smart camera is capable of capturing and processing linear images at over 1,000 frames per second. The edges are identified as numeric pixel values within the linear array of pixels, and the edge location information can be sent out from the circuit in a variety of ways, such as by using a microcontroller and onboard or external digital interface to include serial data such as RS-232/485, USB, Ethernet, or CAN BUS; parallel digital data; or an analog signal. The smart camera system can be integrated into a small package with a relatively small number of parts, reducing size and increasing reliability over the previous imaging system..

Low-cost, high-sensitivity SERS nano-bio-chip for kinase profiling, drug monitoring and environmental detection: a translational platform technology

NASA Astrophysics Data System (ADS)

Chen, Yi; Liu, Logan

2014-03-01

The interaction of biomolecules and solid-state nanomaterials at the nano-bio interfaces is a long-lasting research topic in nanotechnology. Historically, fundamental problems, such as the electron transfer, energy transfer, and plasmonic interaction at the bio-nano interfaces, have been intensively studied, and revolutionary technologies, such as molecular electronics, peptide chips, nanoplasmonic sensors, have been created. With the combined effort of molecular dynamics simulation and surface-enhanced Raman spectroscopy, we studied the external electric field-induced conformation changes of dodecapeptide probes tethered to a nanostructured metallic surface. Through this study, we demonstrated a reversible manipulation of the biomolecule conformations as well as an in situ eletro-optical detection of the subnanometer conformational changes at the bio-nano interfaces. Based on the proof-of-concept established in this study, we further propose a novel nanophotonic peptide phosphorylation sensor for high-sensitive peptide kinase profiling. We have also demonstrated the same SERS nano-bio-chip can be used for environmental monitoring applications, such as detection of contaminants in drinking water at ultralow concentrates. The fabrication of this nanosensor is based on a single step, lithography-less nanomanufacturing process, which can produce hundreds of these chips in several minutes with nearly 100% yield and uniformity. Therefore, the demonstrated research can be readily translated into industrial mass productions.

Bio-inspired microfluidics: The case of the velvet worm

NASA Astrophysics Data System (ADS)

Concha, Andres; Mellado, Paula; Morera-Brenes, Bernal; Sampaio-Costa, Cristiano; Mahadevan, L.; Monge-Najera, Julian

The rapid squirt of a proteinaceous slime jet endow velvet worms (Onychophora) with a unique mechanism for defense from predators and for capturing prey by entangling them in a disordered web that immobilizes their target. However, to date neither qualitative nor quantitative descriptions have been provided for this unique adaptation. We have investigated the mechanism that allows velvet worms the fast oscillatory motion of their oral papillae and the exiting liquid jet that oscillates with frequencies f ~ 30 - 60 Hz. Using anatomical images and high speed videography, we show that even without fast muscular action of the papilla, a strong contraction of the slime reservoir and the geometry of the reservoir-papilla system suffices to accelerate the slime to speeds up to v ~ 5 m /s in about Δt ~ 60 ms. A theoretical analysis and a physical simulacrum allow us to infer that this fast oscillatory motion is the result of an elastohydrodynamic instability driven by the interplay between the elasticity of oral papillae and the fast unsteady flow during squirting. We propose several applications that can be implemented using this instability, ranging from high-throughput droplet production, printing, and micro-nanofiber production among others. A.C was partially supported by Fondecyt Grant 11130075.

Detection method based on Kalman filter for high speed rail defect AE signal on wheel-rail rolling rig

NASA Astrophysics Data System (ADS)

Hao, Qiushi; Shen, Yi; Wang, Yan; Zhang, Xin

2018-01-01

Nondestructive test (NDT) of rails has been carried out intermittently in traditional approaches, which highly restricts the detection efficiency under rapid development of high speed railway nowadays. It is necessary to put forward a dynamic rail defect detection method for rail health monitoring. Acoustic emission (AE) as a practical real-time detection technology takes advantage of dynamic AE signal emitted from plastic deformation of material. Detection capacities of AE on rail defects have been verified due to its sensitivity and dynamic merits. Whereas the application under normal train service circumstance has been impeded by synchronous background noises, which are directly linked to the wheel speed. In this paper, surveys on a wheel-rail rolling rig are performed to investigate defect AE signals with varying speed. A dynamic denoising method based on Kalman filter is proposed and its detection effectiveness and flexibility are demonstrated by theory and computational results. Moreover, after comparative analysis of modelling precision at different speeds, it is predicted that the method is also applicable for high speed condition beyond experiments.

Accretion onto a noncommutative geometry inspired black hole

NASA Astrophysics Data System (ADS)

Kumar, Rahul; Ghosh, Sushant G.

2017-09-01

The spherically symmetric accretion onto a noncommutative (NC) inspired Schwarzschild black hole is treated for a polytropic fluid. The critical accretion rate \\dot{M}, sonic speed a_s and other flow parameters are generalized for the NC inspired static black hole and compared with the results obtained for the standard Schwarzschild black holes. Also explicit expressions for gas compression ratios and temperature profiles below the accretion radius and at the event horizon are derived. This analysis is a generalization of Michel's solution to the NC geometry. Owing to the NC corrected black hole, the accretion flow parameters also have been modified. It turns out that \\dot{M} ≈ {M^2} is still achievable but r_s seems to be substantially decreased due to the NC effects. They in turn do affect the accretion process.

Nanofluidics in two-dimensional layered materials: inspirations from nature.

PubMed

Gao, Jun; Feng, Yaping; Guo, Wei; Jiang, Lei

2017-08-29

With the advance of chemistry, materials science, and nanotechnology, significant progress has been achieved in the design and application of synthetic nanofluidic devices and materials, mimicking the gating, rectifying, and adaptive functions of biological ion channels. Fundamental physics and chemistry behind these novel transport phenomena on the nanoscale have been explored in depth on single-pore platforms. However, toward real-world applications, one major challenge is to extrapolate these single-pore devices into macroscopic materials. Recently, inspired partially by the layered microstructure of nacre, the material design and large-scale integration of artificial nanofluidic devices have stepped into a completely new stage, termed 2D nanofluidics. Unique advantages of the 2D layered materials have been found, such as facile and scalable fabrication, high flux, efficient chemical modification, tunable channel size, etc. These features enable wide applications in, for example, biomimetic ion transport manipulation, molecular sieving, water treatment, and nanofluidic energy conversion and storage. This review highlights the recent progress, current challenges, and future perspectives in this emerging research field of "2D nanofluidics", with emphasis on the thought of bio-inspiration.

Sensing Structures Inspired by Blind Cave Fish

NASA Astrophysics Data System (ADS)

McConney, Michael E.; Chen, Nannan; Lu, David; Anderson, Kyle D.; Hu, Huan; Liu, Chang; Tsukruk, Vladimir V.

2009-03-01

Blind cave fish, with degenerated non-functioning eyes, have evolved to ``see'' their hydrodynamic environment by using the flow receptors of the lateral line system. The hair-cell receptors are encapsulated in a hydrogel-like material, called a cupula, which increases the sensitivity of the hair-cell receptors by coupling their motion to the surrounding flowing media. We characterized the viscoelastic properties and of blind cave fish cupulae by using colloidal-probe spectroscopy in fluid. A photo-patternable hydrogel with similar properties was developed to mimic the fish receptor coupling structure. Flow-based measurements indicated that the hydrogels enhance drag through increased surface area, but also inherent material properties. These bio-inspired structures endowed micro-fabricated flow sensors with sensitivities rivaling that of fish.

D-Amino acid oxidase bio-functionalized platforms: Toward an enhanced enzymatic bio-activity

NASA Astrophysics Data System (ADS)

Herrera, Elisa; Valdez Taubas, Javier; Giacomelli, Carla E.

2015-11-01

The purpose of this work is to study the adsorption process and surface bio-activity of His-tagged D-amino acid oxidase (DAAO) from Rhodotorula gracilis (His6-RgDAAO) as the first step for the development of an electrochemical bio-functionalized platform. With such a purpose this work comprises: (a) the His6-RgDAAO bio-activity in solution determined by amperometry, (b) the adsorption mechanism of His6-RgDAAO on bare gold and carboxylated modified substrates in the absence (substrate/COO-) and presence of Ni(II) (substrate/COO- + Ni(II)) determined by reflectometry, and (c) the bio-activity of the His6-RgDAAO bio-functionalized platforms determined by amperometry. Comparing the adsorption behavior and bio-activity of His6-RgDAAO on these different solid substrates allows understanding the contribution of the diverse interactions responsible for the platform performance. His6-RgDAAO enzymatic performance in solution is highly improved when compared to the previously used pig kidney (pk) DAAO. His6-RgDAAO exhibits an amperometrically detectable bio-activity at concentrations as low as those expected on a bio-functional platform; hence, it is a viable bio-recognition element of D-amino acids to be coupled to electrochemical platforms. Moreover, His6-RgDAAO bio-functionalized platforms exhibit a higher surface activity than pkDAAO physically adsorbed on gold. The platform built on Ni(II) modified substrates present enhanced bio-activity because the surface complexes histidine-Ni(II) provide with site-oriented, native-like enzymes. The adsorption mechanism responsible of the excellent performance of the bio-functionalized platform takes place in two steps involving electrostatic and bio-affinity interactions whose prevalence depends on the degree of surface coverage.

Bio-inspired Nanoparticulate Medical Glues for Minimally Invasive Tissue Repair

PubMed Central

Lee, Yuhan; Xu, Chenjie; Sebastin, Monisha; Lee, Albert; Holwell, Nathan; Xu, Calvin; Miranda-Nieves, David; Mu, Luye; Lin, Charles

2015-01-01

Delivery of tissue glues through small-bore needles or trocars is critical for sealing holes, affixing medical devices, or attaching tissues together during minimally invasive surgeries. Inspired by the granule-packaged glue delivery system of sandcastle worms, we have developed a nanoparticulate formulation of a viscous hydrophobic light-activated adhesive based on poly(glycerol sebacate)-acrylate. Negatively charged alginate was used to stabilize the nanoparticulate surface to significantly reduce its viscosity and to maximize injectability through small-bore needles. The nanoparticulate glues can be concentrated to ~30w/v% dispersions in water that remain localized following injection. With the trigger of a positively charged polymer (e.g., protamine), the nanoparticulate glues can quickly assemble into a viscous glue that exhibits rheological, mechanical and adhesive properties resembling the native poly(glycerol sebacate)-acrylate based glues. This platform should be useful to enable the delivery of viscous glues to augment or replace sutures and staples during minimally invasive procedures. PMID:26227833

Controlling Hydrogel Mechanics via Bio-Inspired Polymer-Nanoparticle Bond Dynamics.

PubMed

Li, Qiaochu; Barrett, Devin G; Messersmith, Phillip B; Holten-Andersen, Niels

2016-01-26

Interactions between polymer molecules and inorganic nanoparticles can play a dominant role in nanocomposite material mechanics, yet control of such interfacial interaction dynamics remains a significant challenge particularly in water. This study presents insights on how to engineer hydrogel material mechanics via nanoparticle interface-controlled cross-link dynamics. Inspired by the adhesive chemistry in mussel threads, we have incorporated iron oxide nanoparticles (Fe3O4 NPs) into a catechol-modified polymer network to obtain hydrogels cross-linked via reversible metal-coordination bonds at Fe3O4 NP surfaces. Unique material mechanics result from the supra-molecular cross-link structure dynamics in the gels; in contrast to the previously reported fluid-like dynamics of transient catechol-Fe(3+) cross-links, the catechol-Fe3O4 NP structures provide solid-like yet reversible hydrogel mechanics. The structurally controlled hierarchical mechanics presented here suggest how to develop hydrogels with remote-controlled self-healing dynamics.

Bio-Inspired Neural Model for Learning Dynamic Models

NASA Technical Reports Server (NTRS)

Duong, Tuan; Duong, Vu; Suri, Ronald

2009-01-01

A neural-network mathematical model that, relative to prior such models, places greater emphasis on some of the temporal aspects of real neural physical processes, has been proposed as a basis for massively parallel, distributed algorithms that learn dynamic models of possibly complex external processes by means of learning rules that are local in space and time. The algorithms could be made to perform such functions as recognition and prediction of words in speech and of objects depicted in video images. The approach embodied in this model is said to be "hardware-friendly" in the following sense: The algorithms would be amenable to execution by special-purpose computers implemented as very-large-scale integrated (VLSI) circuits that would operate at relatively high speeds and low power demands.

Gravitational radiation, inspiraling binaries, and cosmology

NASA Technical Reports Server (NTRS)

Chernoff, David F.; Finn, Lee S.

1993-01-01

We show how to measure cosmological parameters using observations of inspiraling binary neutron star or black hole systems in one or more gravitational wave detectors. To illustrate, we focus on the case of fixed mass binary systems observed in a single Laser Interferometer Gravitational-wave Observatory (LIGO)-like detector. Using realistic detector noise estimates, we characterize the rate of detections as a function of a threshold SNR Rho(0), H0, and the binary 'chirp' mass. For Rho(0) = 8, H0 = 100 km/s/Mpc, and 1.4 solar mass neutron star binaries, the sample has a median redshift of 0.22. Under the same assumptions but independent of H0, a conservative rate density of coalescing binaries implies LIGO will observe about 50/yr binary inspiral events. The precision with which H0 and the deceleration parameter q0 may be determined depends on the number of observed inspirals. For fixed mass binary systems, about 100 observations with Rho(0) = 10 in the LIGO will give H0 to 10 percent in an Einstein-DeSitter cosmology, and 3000 will give q0 to 20 percent. For the conservative rate density of coalescing binaries, 100 detections with Rho(0) = 10 will require about 4 yrs.

Flectofin: a hingeless flapping mechanism inspired by nature.

PubMed

Lienhard, J; Schleicher, S; Poppinga, S; Masselter, T; Milwich, M; Speck, T; Knippers, J

2011-12-01

This paper presents a novel biomimetic approach to the kinematics of deployable systems for architectural purposes. Elastic deformation of the entire structure replaces the need for local hinges. This change becomes possible by using fibre-reinforced polymers (FRP) such as glass fibre reinforced polymer (GFRP) that can combine high tensile strength with low bending stiffness, thus offering a large range of calibrated elastic deformations. The employment of elasticity within a structure facilitates not only the generation of complex geometries, but also takes the design space a step further by creating elastic kinetic structures, here referred to as pliable structures. In this paper, the authors give an insight into the abstraction strategies used to derive elastic kinetics from plants, which show a clear interrelation of form, actuation and kinematics. Thereby, the focus will be on form-finding and simulation methods which have been adopted to generate a biomimetic principle which is patented under the name Flectofin®. This bio inspired hingeless flapping device is inspired by the valvular pollination mechanism that was derived and abstracted from the kinematics found in the Bird-Of-Paradise flower (Strelitzia reginae, Strelitziaceae).

Chalcogenide glass sensors for bio-molecule detection

NASA Astrophysics Data System (ADS)

Lucas, Pierre; Coleman, Garrett J.; Cantoni, Christopher; Jiang, Shibin; Luo, Tao; Bureau, Bruno; Boussard-Pledel, Catherine; Troles, Johann; Yang, Zhiyong

2017-02-01

engineering enable the design of opto-electrophoretic sensors that permit simultaneous capture and detection of hazardous bio-molecules such as bacteria, virus and proteins using a conducting glass that serves as both an electrode and an optical elements. Upon adequate spectral analysis such as Principal Component Analysis (PCA) or Partial Least Square (PLS) regression these devices enable highly selective identification of hazardous microorganism such as different strains of bacteria and food pathogens.

Bio-inspired cofacial Fe porphyrin dimers for efficient electrocatalytic CO2 to CO conversion: Overpotential tuning by substituents at the porphyrin rings.

PubMed

Zahran, Zaki N; Mohamed, Eman A; Naruta, Yoshinori

2016-04-18

Efficient reduction of CO2 into useful carbon resources particularly CO is an essential reaction for developing alternate sources of fuels and for reducing the greenhouse effect of CO2. The binuclear Ni, Fe-containing carbon monoxide dehydrogenase (CODHs) efficiently catalyzes the reduction of CO2 to CO. The location of Ni and Fe at proper positions allows their cooperation for CO2 to CO conversion through a push-pull mechanism. Bio-inspired from CODHs, we used several cofacial porphyrin dimers with different substituents as suitable ligands for holding two Fe ions with suitable Fe-Fe separation distance to efficiently and selectively promote CO2 to CO conversion with high turnover frequencies, TOFs. The substituents on the porphyrin rings greatly affect the catalysis process. By introducing electron-withdrawing/-donating groups, e.g. electron-withdrawing perfluorophenyl, at all meso positions of the porphyrin rings, the catalysis overpotential, η was minimized by ≈0.3 V compared to that obtained by introducing electron-donating mesityl groups. The Fe porphyrin dimers among reported catalysts are the most efficient ones for CO2 to CO conversion. Control experiments indicate that the high performance of the current CO2 to CO conversion catalysts is due to the presence of binuclear Fe centers at suitable Fe-Fe separation distance.

Bio-inspired cofacial Fe porphyrin dimers for efficient electrocatalytic CO2 to CO conversion: Overpotential tuning by substituents at the porphyrin rings

NASA Astrophysics Data System (ADS)

Zahran, Zaki N.; Mohamed, Eman A.; Naruta, Yoshinori

2016-04-01

Efficient reduction of CO2 into useful carbon resources particularly CO is an essential reaction for developing alternate sources of fuels and for reducing the greenhouse effect of CO2. The binuclear Ni, Fe-containing carbon monoxide dehydrogenase (CODHs) efficiently catalyzes the reduction of CO2 to CO. The location of Ni and Fe at proper positions allows their cooperation for CO2 to CO conversion through a push-pull mechanism. Bio-inspired from CODHs, we used several cofacial porphyrin dimers with different substituents as suitable ligands for holding two Fe ions with suitable Fe-Fe separation distance to efficiently and selectively promote CO2 to CO conversion with high turnover frequencies, TOFs. The substituents on the porphyrin rings greatly affect the catalysis process. By introducing electron-withdrawing/-donating groups, e.g. electron-withdrawing perfluorophenyl, at all meso positions of the porphyrin rings, the catalysis overpotential, η was minimized by ≈0.3 V compared to that obtained by introducing electron-donating mesityl groups. The Fe porphyrin dimers among reported catalysts are the most efficient ones for CO2 to CO conversion. Control experiments indicate that the high performance of the current CO2 to CO conversion catalysts is due to the presence of binuclear Fe centers at suitable Fe-Fe separation distance.

On gravitational waves in Born-Infeld inspired non-singular cosmologies

NASA Astrophysics Data System (ADS)

Beltrán Jiménez, Jose; Heisenberg, Lavinia; Olmo, Gonzalo J.; Rubiera-Garcia, Diego

2017-10-01

We study the evolution of gravitational waves for non-singular cosmological solutions within the framework of Born-Infeld inspired gravity theories, with special emphasis on the Eddington-inspired Born-Infeld theory. We review the existence of two types of non-singular cosmologies, namely bouncing and asymptotically Minkowski solutions, from a perspective that makes their features more apparent. We study in detail the propagation of gravitational waves near these non-singular solutions and carefully discuss the origin and severity of the instabilities and strong coupling problems that appear. We also investigate the role of the adiabatic sound speed of the matter sector in the regularisation of the gravitational waves evolution. We extend our analysis to more general Born-Infeld inspired theories where analogous solutions are found. As a general conclusion, we obtain that the bouncing solutions are generally more prone to instabilities, while the asymptotically Minkowski solutions can be rendered stable, making them appealing models for the early universe.

On gravitational waves in Born-Infeld inspired non-singular cosmologies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jiménez, Jose Beltrán; Heisenberg, Lavinia; Olmo, Gonzalo J.

We study the evolution of gravitational waves for non-singular cosmological solutions within the framework of Born-Infeld inspired gravity theories, with special emphasis on the Eddington-inspired Born-Infeld theory. We review the existence of two types of non-singular cosmologies, namely bouncing and asymptotically Minkowski solutions, from a perspective that makes their features more apparent. We study in detail the propagation of gravitational waves near these non-singular solutions and carefully discuss the origin and severity of the instabilities and strong coupling problems that appear. We also investigate the role of the adiabatic sound speed of the matter sector in the regularisation of themore » gravitational waves evolution. We extend our analysis to more general Born-Infeld inspired theories where analogous solutions are found. As a general conclusion, we obtain that the bouncing solutions are generally more prone to instabilities, while the asymptotically Minkowski solutions can be rendered stable, making them appealing models for the early universe.« less

Nonimaging speckle interferometry for high-speed nanometer-scale position detection.

PubMed

van Putten, E G; Lagendijk, A; Mosk, A P

2012-03-15

We experimentally demonstrate a nonimaging approach to displacement measurement for complex scattering materials. By spatially controlling the wavefront of the light that incidents on the material, we concentrate the scattered light in a focus on a designated position. This wavefront acts as a unique optical fingerprint that enables precise position detection of the illuminated material by simply measuring the intensity in the focus. By combining two fingerprints we demonstrate position detection along one in-plane dimension with a displacement resolution of 2.1 nm. As our approach does not require an image of the scattered field, it is possible to employ fast nonimaging detectors to enable high-speed position detection of scattering materials.

Shuttlecock detection system for fully-autonomous badminton robot with two high-speed video cameras

NASA Astrophysics Data System (ADS)

Masunari, T.; Yamagami, K.; Mizuno, M.; Une, S.; Uotani, M.; Kanematsu, T.; Demachi, K.; Sano, S.; Nakamura, Y.; Suzuki, S.

2017-02-01

Two high-speed video cameras are successfully used to detect the motion of a flying shuttlecock of badminton. The shuttlecock detection system is applied to badminton robots that play badminton fully autonomously. The detection system measures the three dimensional position and velocity of a flying shuttlecock, and predicts the position where the shuttlecock falls to the ground. The badminton robot moves quickly to the position where the shuttle-cock falls to, and hits the shuttlecock back into the opponent's side of the court. In the game of badminton, there is a large audience, and some of them move behind a flying shuttlecock, which are a kind of background noise and makes it difficult to detect the motion of the shuttlecock. The present study demonstrates that such noises can be eliminated by the method of stereo imaging with two high-speed cameras.

Smart Drug Delivery System-Inspired Enzyme-Linked Immunosorbent Assay Based on Fluorescence Resonance Energy Transfer and Allochroic Effect Induced Dual-Modal Colorimetric and Fluorescent Detection.

PubMed

Miao, Luyang; Zhu, Chengzhou; Jiao, Lei; Li, He; Du, Dan; Lin, Yuehe; Wei, Qin

2018-02-06

Numerous analytical techniques have been undertaken for the detection of protein biomarkers because of their extensive and significant applications in clinical diagnosis, whereas there are few strategies to develop dual-readout immunosensors to achieve more accurate results. To the best of our knowledge, inspired by smart drug delivery system (DDS), a novel pH-responsive modified enzyme-linked immunosorbent assay (ELISA) was innovatively developed for the first time, realizing dual-modal colorimetric and fluorescent detection of cardiac troponin I (cTnI). Curcumin (CUR) was elaborately selected as a reporter molecule, which played the same role of drugs in DDS based on the following considerations: (1) CUR can be used as a kind of pH indicator by the inherited allochroic effect induced by basic pH value; (2) the fluorescence of CUR can be quenched by certain nanocarriers as the acceptor because of the occurrence of fluorescence resonance energy transfer (FRET), while recovered by the stimuli of basic pH value, which can produce "signal-on" fluorescence detection. Three-dimensional MoS 2 nanoflowers (3D-MoS 2 NFs) were employed in immobilizing CUR to constitute a nanoprobe for the determination of cTnI by virtue of good biocompatibility, high absorption capacity, and fluorescence quench efficiency toward CUR. The proposed DDS-inspired ELISA offered dual-modal colorimetric and fluorescent detection of cTnI, thereby meeting the reliable and precise analysis requirements. We believe that the developed dual-readout ELISA will create a new avenue and bring innovative inspirations for biological detections.

Inspired Responses

ERIC Educational Resources Information Center

Steele, Carol Frederick

2011-01-01

In terms of teacher quality, Steele believes the best teachers have reached a stage she terms inspired, and that teachers move progressively through the stages of unaware, aware, and capable until the most reflective teachers finally reach the inspired level. Inspired teachers have a wide repertoire of teaching and class management techniques and…

Test-retest reliability and smallest detectable change of the Bristol Impact of Hypermobility (BIoH) questionnaire.

PubMed

Palmer, S; Manns, S; Cramp, F; Lewis, R; Clark, E M

2017-12-01

The Bristol Impact of Hypermobility (BIoH) questionnaire is a patient-reported outcome measure developed in conjunction with adults with Joint Hypermobility Syndrome (JHS). It has demonstrated strong concurrent validity with the Short Form-36 (SF-36) physical component score but other psychometric properties have yet to be established. This study aimed to determine its test-retest reliability and smallest detectable change (SDC). A test-retest reliability study. Participants were recruited from the Hypermobility Syndromes Association, a patient organisation in the United Kingdom. Recruitment packs were sent to 1080 adults who had given permission to be contacted about research. BIoH and SF-36 questionnaires were administered at baseline and repeated two weeks later. An 11-point global rating of change scale (-5 to +5) was also administered at two weeks. Test-retest analysis and calculation of the SDC was conducted on 'stable' patients (defined as global rating of change -1 to +1). 462 responses were received. 233 patients reported a 'stable' condition and were included in analysis (95% women; mean (SD) age 44.5 (13.9) years; BIoH score 223.6 (54.0)). The BIoH questionnaire demonstrated excellent test-retest reliability (ICC 0.923, 95% CI 0.900-0.940). The SDC was 42 points (equivalent to 19% of the mean baseline score). The SF-36 physical and mental component scores demonstrated poorer test-retest reliability and larger SDCs (as a proportion of the mean baseline scores). The results provide further evidence of the potential of the BIoH questionnaire to underpin research and clinical practice for people with JHS. Copyright © 2017 Elsevier Ltd. All rights reserved.

Bio-inspired Optimal Locomotion Reconfigurability of Quadruped Rovers using Central Pattern Generators

NASA Astrophysics Data System (ADS)

Bohra, Murtaza

Legged rovers are often considered as viable solutions for traversing unknown terrain. This work addresses the optimal locomotion reconfigurability of quadruped rovers, which consists of obtaining optimal locomotion modes, and transitioning between them. A 2D sagittal plane rover model is considered based on a domestic cat. Using a Genetic Algorithm, the gait, pose and control variables that minimize torque or maximize speed are found separately. The optimization approach takes into account the elimination of leg impact, while considering the entire variable spectrum. The optimal solutions are consistent with other works on gait optimization, and are similar to gaits found in quadruped animals as well. An online model-free gait planning framework is also implemented, that is based on Central Pattern Generators is implemented. It is used to generate joint and control trajectories for any arbitrarily varying speed profile, and shown to regulate locomotion transition and speed modulation, both endogenously and continuously.

Direct detection of Mycobacterium tuberculosis rifampin resistance in bio-safe stained sputum smears.

PubMed

Lavania, Surabhi; Anthwal, Divya; Bhalla, Manpreet; Singh, Nagendra; Haldar, Sagarika; Tyagi, Jaya Sivaswami

2017-01-01

Direct smear microscopy of sputum forms the mainstay of TB diagnosis in resource-limited settings. Stained sputum smear slides can serve as a ready-made resource to transport sputum for molecular drug susceptibility testing. However, bio-safety is a major concern during transport of sputum/stained slides and for laboratory workers engaged in processing Mycobacterium tuberculosis infected sputum specimens. In this study, a bio-safe USP (Universal Sample Processing) concentration-based sputum processing method (Bio-safe method) was assessed on 87 M. tuberculosis culture positive sputum samples. Samples were processed for Ziehl-Neelsen (ZN) smear, liquid culture and DNA isolation. DNA isolated directly from sputum was subjected to an IS6110 PCR assay. Both sputum DNA and DNA extracted from bio-safe ZN concentrated smear slides were subjected to rpoB PCR and simultaneously assessed by DNA sequencing for determining rifampin (RIF) resistance. All sputum samples were rendered sterile by Bio-safe method. Bio-safe smears exhibited a 5% increment in positivity over direct smear with a 14% increment in smear grade status. All samples were positive for IS6110 and rpoB PCR. Thirty four percent samples were RIF resistant by rpoB PCR product sequencing. A 100% concordance (κ value = 1) was obtained between sequencing results derived from bio-safe smear slides and bio-safe sputum. This study demonstrates that Bio-safe method can address safety issues associated with sputum processing, provide an efficient alternative to sample transport in the form of bio-safe stained concentrated smear slides and can also provide information on drug (RIF) resistance by direct DNA sequencing.

Bio-inspired formation of functional calcite/metal oxide nanoparticle composites.

PubMed

Kim, Yi-Yeoun; Schenk, Anna S; Walsh, Dominic; Kulak, Alexander N; Cespedes, Oscar; Meldrum, Fiona C

2014-01-21

Biominerals are invariably composite materials, where occlusion of organic macromolecules within single crystals can significantly modify their properties. In this article, we take inspiration from this biogenic strategy to generate composite crystals in which magnetite (Fe3O4) and zincite (ZnO) nanoparticles are embedded within a calcite single crystal host, thereby endowing it with new magnetic or optical properties. While growth of crystals in the presence of small molecules, macromolecules and particles can lead to their occlusion within the crystal host, this approach requires particles with specific surface chemistries. Overcoming this limitation, we here precipitate crystals within a nanoparticle-functionalised xyloglucan gel, where gels can also be incorporated within single crystals, according to their rigidity. This method is independent of the nanoparticle surface chemistry and as the gel maintains its overall structure when occluded within the crystal, the nanoparticles are maintained throughout the crystal, preventing, for example, their movement and accumulation at the crystal surface during crystal growth. This methodology is expected to be quite general, and could be used to endow a wide range of crystals with new functionalities.

Highly sensitive electrochemical detection of human telomerase activity based on bio-barcode method.

PubMed

Li, Ying; Liu, Bangwei; Li, Xia; Wei, Qingli

2010-07-15

In the present study, an electrochemical method for highly sensitive detection of human telomerase activity was developed based on bio-barcode amplification assay. Telomerase was extracted from HeLa cells, then the extract was mixed with telomerase substrate (TS) primer to perform extension reaction. The extension product was hybridized with the capture DNA immobilized on the Au electrode and then reacted with the signal DNA on Au nanoparticles to form a sandwich hybridization mode. Electrochemical signals were generated by chronocoulometric interrogation of [Ru(NH(3))(6)](3+) that quantitatively binds to the DNA on Au nanoparticles via electrostatic interaction. This method can detect the telomerase activity from as little as 10 cultured cancer cells without the polymerase chain reaction (PCR) amplification of telomerase extension product. Copyright (c) 2010 Elsevier B.V. All rights reserved.

Direct detection of Mycobacterium tuberculosis rifampin resistance in bio-safe stained sputum smears

PubMed Central

Lavania, Surabhi; Anthwal, Divya; Bhalla, Manpreet; Singh, Nagendra; Haldar, Sagarika; Tyagi, Jaya Sivaswami

2017-01-01

Direct smear microscopy of sputum forms the mainstay of TB diagnosis in resource-limited settings. Stained sputum smear slides can serve as a ready-made resource to transport sputum for molecular drug susceptibility testing. However, bio-safety is a major concern during transport of sputum/stained slides and for laboratory workers engaged in processing Mycobacterium tuberculosis infected sputum specimens. In this study, a bio-safe USP (Universal Sample Processing) concentration-based sputum processing method (Bio-safe method) was assessed on 87 M. tuberculosis culture positive sputum samples. Samples were processed for Ziehl-Neelsen (ZN) smear, liquid culture and DNA isolation. DNA isolated directly from sputum was subjected to an IS6110 PCR assay. Both sputum DNA and DNA extracted from bio-safe ZN concentrated smear slides were subjected to rpoB PCR and simultaneously assessed by DNA sequencing for determining rifampin (RIF) resistance. All sputum samples were rendered sterile by Bio-safe method. Bio-safe smears exhibited a 5% increment in positivity over direct smear with a 14% increment in smear grade status. All samples were positive for IS6110 and rpoB PCR. Thirty four percent samples were RIF resistant by rpoB PCR product sequencing. A 100% concordance (κ value = 1) was obtained between sequencing results derived from bio-safe smear slides and bio-safe sputum. This study demonstrates that Bio-safe method can address safety issues associated with sputum processing, provide an efficient alternative to sample transport in the form of bio-safe stained concentrated smear slides and can also provide information on drug (RIF) resistance by direct DNA sequencing. PMID:29216262

Novel features and enhancements in BioBin, a tool for the biologically inspired binning and association analysis of rare variants

PubMed Central

Byrska-Bishop, Marta; Wallace, John; Frase, Alexander T; Ritchie, Marylyn D

2018-01-01

Abstract Motivation BioBin is an automated bioinformatics tool for the multi-level biological binning of sequence variants. Herein, we present a significant update to BioBin which expands the software to facilitate a comprehensive rare variant analysis and incorporates novel features and analysis enhancements. Results In BioBin 2.3, we extend our software tool by implementing statistical association testing, updating the binning algorithm, as well as incorporating novel analysis features providing for a robust, highly customizable, and unified rare variant analysis tool. Availability and implementation The BioBin software package is open source and freely available to users at http://www.ritchielab.com/software/biobin-download Contact mdritchie@geisinger.edu Supplementary information Supplementary data are available at Bioinformatics online. PMID:28968757

Mineral-Enhanced Polyacrylic Acid Hydrogel as an Oyster-Inspired Organic-Inorganic Hybrid Adhesive.

PubMed

Li, Ang; Jia, Yunfei; Sun, Shengtong; Xu, Yisheng; Minsky, Burcu Baykal; Stuart, M A Cohen; Cölfen, Helmut; von Klitzing, Regine; Guo, Xuhong

2018-03-28

Underwater adhesion is crucial to many marine life forms living a sedentary lifestyle. Amongst them, mussel adhesion has been mostly studied, which inspires numerous investigations of 3,4-dihydroxyphenylalanine (DOPA)-based organic adhesives. In contrast, reef-building oysters represent another important "inorganic" strategy of marine molluscs for adhesion by generating biomineralized organic-inorganic adhesives, which is still rarely studied and no synthetic analogues have ever been reported so far. Here, a novel type of oyster-inspired organic-inorganic adhesive based on a biomineralized polyelectrolyte hydrogel is reported, which consists of polyacrylic acid physically cross-linked by very small amorphous calcium carbonate nanoparticles (<3 nm). The mineral-enhanced polyelectrolyte hydrogel adhesive is shown to be injectable, reusable, and optically clear upon curing in air. Moreover, comparable adhesion performance to DOPA-based adhesives is found for the hydrogel adhesive in both dry and wet conditions, which can even be further enhanced by introducing a small amount of second large cross-linker such as negatively charged nanoparticles. The present mineral hydrogel represents a new type of bio-inspired organic-inorganic adhesive that may find a variety of potential applications in adhesive chemistry.

LDHs as electrode materials for electrochemical detection and energy storage: supercapacitor, battery and (bio)-sensor.

PubMed

Mousty, Christine; Leroux, Fabrice

2012-11-01

From an exhaustive overview based on applicative academic literature and patent domain, the relevance of Layered Double Hydroxide (LDHs) as electrode materials for electrochemical detection of organic molecules having environmental or health impact and energy storage is evaluated. Specifically the focus is driven on their application as supercapacitor, alkaline or lithium battery and (bio)-sensor. Inherent to the high versatility of their chemical composition, charge density, anion exchange capability, LDH-based materials are extensively studied and their performances for such applications are reported. Indeed the analytical characteristics (sensitivity and detection limit) of LDH-based electrodes are scrutinized, and their specific capacity or capacitance as electrode battery or supercapacitor materials, are detailed.

Bio-inspired Cryo-ink Preserves Red Blood Cell Phenotype and Function during Nanoliter Vitrification

PubMed Central

Assal, Rami El; Guven, Sinan; Gurkan, Umut Atakan; Gozen, Irep; Shafiee, Hadi; Dalbeyber, Sedef; Abdalla, Noor; Thomas, Gawain; Fuld, Wendy; Illigens, Ben M.W.; Estanislau, Jessica; Khoory, Joseph; Kaufman, Richard; Zylberberg, Claudia; Lindeman, Neal; Wen, Qi; Ghiran, Ionita; Demirci, Utkan

2014-01-01

Current red blood cell cryopreservation methods utilize bulk volumes, causing cryo-injury of cells, which results in irreversible disruption of cell morphology, mechanics, and function. An innovative approach to preserve human red blood cell morphology, mechanics, and function following vitrification in nanoliter volumes is developed using a novel cryo-ink integrated with a bio-printing approach. PMID:25047246

Rapid detection of malignant bio-species using digital holographic pattern recognition and nano-photonics

NASA Astrophysics Data System (ADS)

Sarkisov, Sergey S.; Kukhtareva, Tatiana; Kukhtarev, Nickolai V.; Curley, Michael J.; Edwards, Vernessa; Creer, Marylyn

2013-03-01

There is a great need for rapid detection of bio-hazardous species particularly in applications to food safety and biodefense. It has been recently demonstrated that the colonies of various bio-species could be rapidly detected using culture-specific and reproducible patterns generated by scattered non-coherent light. However, the method heavily relies on a digital pattern recognition algorithm, which is rather complex, requires substantial computational power and is prone to ambiguities due to shift, scale, or orientation mismatch between the analyzed pattern and the reference from the library. The improvement could be made, if, in addition to the intensity of the scattered optical wave, its phase would be also simultaneously recorded and used for the digital holographic pattern recognition. In this feasibility study the research team recorded digital Gabor-type (in-line) holograms of colonies of micro-organisms, such as Salmonella with a laser diode as a low-coherence light source and a lensless high-resolution (2.0x2.0 micron pixel pitch) digital image sensor. The colonies were grown in conventional Petri dishes using standard methods. The digitally recorded holograms were used for computational reconstruction of the amplitude and phase information of the optical wave diffracted on the colonies. Besides, the pattern recognition of the colony fragments using the cross-correlation between the digital hologram was also implemented. The colonies of mold fungi Altenaria sp, Rhizophus, sp, and Aspergillus sp have been also generating nano-colloidal silver during their growth in specially prepared matrices. The silver-specific plasmonic optical extinction peak at 410-nm was also used for rapid detection and growth monitoring of the fungi colonies.

A feasibility study of damage detection in beams using high-speed camera (Conference Presentation)

NASA Astrophysics Data System (ADS)

Wan, Chao; Yuan, Fuh-Gwo

2017-04-01

In this paper a method for damage detection in beam structures using high-speed camera is presented. Traditional methods of damage detection in structures typically involve contact (i.e., piezoelectric sensor or accelerometer) or non-contact sensors (i.e., laser vibrometer) which can be costly and time consuming to inspect an entire structure. With the popularity of the digital camera and the development of computer vision technology, video cameras offer a viable capability of measurement including higher spatial resolution, remote sensing and low-cost. In the study, a damage detection method based on the high-speed camera was proposed. The system setup comprises a high-speed camera and a line-laser which can capture the out-of-plane displacement of a cantilever beam. The cantilever beam with an artificial crack was excited and the vibration process was recorded by the camera. A methodology called motion magnification, which can amplify subtle motions in a video is used for modal identification of the beam. A finite element model was used for validation of the proposed method. Suggestions for applications of this methodology and challenges in future work will be discussed.

Actions, Observations, and Decision-Making: Biologically Inspired Strategies for Autonomous Aerial Vehicles

NASA Technical Reports Server (NTRS)

Pisanich, Greg; Ippolito, Corey; Plice, Laura; Young, Larry A.; Lau, Benton

2003-01-01

This paper details the development and demonstration of an autonomous aerial vehicle embodying search and find mission planning and execution srrategies inspired by foraging behaviors found in biology. It begins by describing key characteristics required by an aeria! explorer to support science and planetary exploration goals, and illustrates these through a hypothetical mission profile. It next outlines a conceptual bio- inspired search and find autonomy architecture that implements observations, decisions, and actions through an "ecology" of producer, consumer, and decomposer agents. Moving from concepts to development activities, it then presents the results of mission representative UAV aerial surveys at a Mars analog site. It next describes hardware and software enhancements made to a commercial small fixed-wing UAV system, which inc!nde a ncw dpvelopnent architecture that also provides hardware in the loop simulation capability. After presenting the results of simulated and actual flights of bioinspired flight algorithms, it concludes with a discussion of future development to include an expansion of system capabilities and field science support.

tmBioC: improving interoperability of text-mining tools with BioC.

PubMed

Khare, Ritu; Wei, Chih-Hsuan; Mao, Yuqing; Leaman, Robert; Lu, Zhiyong

2014-01-01

The lack of interoperability among biomedical text-mining tools is a major bottleneck in creating more complex applications. Despite the availability of numerous methods and techniques for various text-mining tasks, combining different tools requires substantial efforts and time owing to heterogeneity and variety in data formats. In response, BioC is a recent proposal that offers a minimalistic approach to tool interoperability by stipulating minimal changes to existing tools and applications. BioC is a family of XML formats that define how to present text documents and annotations, and also provides easy-to-use functions to read/write documents in the BioC format. In this study, we introduce our text-mining toolkit, which is designed to perform several challenging and significant tasks in the biomedical domain, and repackage the toolkit into BioC to enhance its interoperability. Our toolkit consists of six state-of-the-art tools for named-entity recognition, normalization and annotation (PubTator) of genes (GenNorm), diseases (DNorm), mutations (tmVar), species (SR4GN) and chemicals (tmChem). Although developed within the same group, each tool is designed to process input articles and output annotations in a different format. We modify these tools and enable them to read/write data in the proposed BioC format. We find that, using the BioC family of formats and functions, only minimal changes were required to build the newer versions of the tools. The resulting BioC wrapped toolkit, which we have named tmBioC, consists of our tools in BioC, an annotated full-text corpus in BioC, and a format detection and conversion tool. Furthermore, through participation in the 2013 BioCreative IV Interoperability Track, we empirically demonstrate that the tools in tmBioC can be more efficiently integrated with each other as well as with external tools: Our experimental results show that using BioC reduces >60% in lines of code for text-mining tool integration. The tmBioC toolkit

A speeded-up saliency region-based contrast detection method for small targets

NASA Astrophysics Data System (ADS)

Li, Zhengjie; Zhang, Haiying; Bai, Jiaojiao; Zhou, Zhongjun; Zheng, Huihuang

2018-04-01

To cope with the rapid development of the real applications for infrared small targets, the researchers have tried their best to pursue more robust detection methods. At present, the contrast measure-based method has become a promising research branch. Following the framework, in this paper, a speeded-up contrast measure scheme is proposed based on the saliency detection and density clustering. First, the saliency region is segmented by saliency detection method, and then, the Multi-scale contrast calculation is carried out on it instead of traversing the whole image. Second, the target with a certain "integrity" property in spatial is exploited to distinguish the target from the isolated noises by density clustering. Finally, the targets are detected by a self-adaptation threshold. Compared with time-consuming MPCM (Multiscale Patch Contrast Map), the time cost of the speeded-up version is within a few seconds. Additional, due to the use of "clustering segmentation", the false alarm caused by heavy noises can be restrained to a lower level. The experiments show that our method has a satisfied FASR (False alarm suppression ratio) and real-time performance compared with the state-of-art algorithms no matter in cloudy sky or sea-sky background.

Development of a Four-Fin Bio-Inspired UUV: CFD Studies

DTIC Science & Technology

2012-09-04

6.5ʺ″, V= 1kt, δ = -43.6°. .................................. 17   Fig. 32. Particles traces just near stroke reversal of the front and rear fins...have been studied to understand how certain aquatic animals achieve their high levels of controllability. Blake [1] determined that in low- speed...fin, the amplitude of the flapping and starting location of the down stroke . These simulations were performed in order to evaluate the hydrodynamic

The hybrid bio-inspired aerial vehicle: Concept and SIMSCAPE flight simulation.

PubMed

Tao Zhang; Su, Steven; Nguyen, Hung T

2016-08-01

This paper introduces a Silver Gull-inspired hybrid aerial vehicle, the Super Sydney Silver Gull (SSSG), which is able to vary its structure, under different manoeuvre requirements, to implement three flight modes: the flapping wing flight, the fixed wing flight, and the quadcopter flight (the rotary wing flight of Unmanned Air Vehicle). Specifically, through proper mechanism design and flight mode transition, the SSSG can imitate the Silver Gull's flight gesture during flapping flight, save power consuming by switching to the fixed wing flight mode during long-range cruising, and hover at targeted area when transferring to quadcopter flight mode. Based on the aerodynamic models, the Simscape, a product of MathWorks, is used to simulate and analyse the performance of the SSSG's flight modes. The entity simulation results indicate that the created SSSG's 3D model is feasible and ready to be manufactured for further flight tests.

A smart magnetic nanoplatform for synergistic anticancer therapy: manoeuvring mussel-inspired functional magnetic nanoparticles for pH responsive anticancer drug delivery and hyperthermia.

PubMed

Sasikala, Arathyram Ramachandra Kurup; GhavamiNejad, Amin; Unnithan, Afeesh Rajan; Thomas, Reju George; Moon, Myeongju; Jeong, Yong Yeon; Park, Chan Hee; Kim, Cheol Sang

2015-11-21

We report the versatile design of a smart nanoplatform for thermo-chemotherapy treatment of cancer. For the first time in the literature, our design takes advantage of the outstanding properties of mussel-inspired multiple catecholic groups - presenting a unique copolymer poly(2-hydroxyethyl methacrylate-co-dopamine methacrylamide) p(HEMA-co-DMA) to surface functionalize the superparamagnetic iron oxide nanoparticles as well as to conjugate borate containing anticancer drug bortezomib (BTZ) in a pH-dependent manner for the synergistic anticancer treatment. The unique multiple anchoring groups can be used to substantially improve the affinity of the ligands to the surfaces of the nanoparticles to form ultrastable iron oxide nanoparticles with control over their hydrodynamic diameter and interfacial chemistry. Thus the BTZ-incorporated-bio-inspired-smart magnetic nanoplatform will act as a hyperthermic agent that delivers heat when an alternating magnetic field is applied while the BTZ-bound catechol moieties act as chemotherapeutic agents in a cancer environment by providing pH-dependent drug release for the synergistic thermo-chemotherapy application. The anticancer efficacy of these bio-inspired multifunctional smart magnetic nanoparticles was tested both in vitro and in vivo and found that these unique magnetic nanoplatforms can be established to endow for the next generation of nanomedicine for efficient and safe cancer therapy.

Bio-inspired smart single asymmetric hourglass nanochannels for continuous shape and ion transport control.

PubMed

Zhang, Huacheng; Hou, Xu; Yang, Zhe; Yan, Dadong; Li, Lin; Tian, Ye; Wang, Huanting; Jiang, Lei

2015-02-18

Inspired by biological asymmetric ion channels, new shape-tunable and pH-responsive asymmetric hourglass single nanochannel systems demonstrate unique ion-transport properties. It is found that the change in shape and pH cooperatively control the ion transport within the nanochannel ranging from asymmetric shape with asymmetric ion transport, to asymmetric shape with symmetric ion transport and symmetric shape with symmetric ion transport. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Highly robust hydrogen generation by bio-inspired Ir complexes for dehydrogenation of formic acid in water: Experimental and theoretical mechanistic investigations at different pH

DOE PAGES

Wang, Wan -Hui; Fujita, Etsuko; Ertem, Mehmed Z.; ...

2015-07-30

Hydrogen generation from formic acid (FA), one of the most promising hydrogen storage materials, has attracted much attention due to the demand for the development of renewable energy carriers. Catalytic dehydrogenation of FA in an efficient and green manner remains challenging. Here, we report a series of bio-inspired Ir complexes for highly robust and selective hydrogen production from FA in aqueous solutions without organic solvents or additives. One of these complexes bearing an imidazoline moiety (complex 6) achieved a turnover frequency (TOF) of 322,000 h⁻¹ at 100 °C, which is higher than ever reported. The novel catalysts are very stablemore » and applicable in highly concentrated FA. For instance, complex 3 (1 μmol) affords an unprecedented turnover number (TON) of 2,050,000 at 60 °C. Deuterium kinetic isotope effect experiments and density functional theory (DFT) calculations employing a “speciation” approach demonstrated a change in the rate-determining step with increasing solution pH. This study provides not only more insight into the mechanism of dehydrogenation of FA but also offers a new principle for the design of effective homogeneous organometallic catalysts for H₂ generation from FA.« less

Recent advances in synthesis of three-dimensional porous graphene and its applications in construction of electrochemical (bio)sensors for small biomolecules detection.

PubMed

Lu, Lu

2018-07-01

Electrochemical (bio)sensors have attracted much attention due to their high sensitivity, fast response time, biocompatibility, low cost and easy miniaturization. Specially, ever-growing necessity and interest have given rise to the fast development of electrochemical (bio)sensors for the detection of small biomolecules. They play enormous roles in the life processes with various biological function, such as life signal transmission, genetic expression and metabolism. Moreover, their amount in body can be used as an indicator for diagnosis of many diseases. For example, an abnormal concentration of blood glucose can indicate hyperglycemia or hypoglycemia. Graphene (GR) shows great applications in electrochemical (bio)sensors. Compared with two-dimensional (2D) GR that is inclined to stack together due to the strong π-π interaction, monolithic 3D porous GR has larger specific area, superior mechanical strength, better stability, higher conductivity and electrocatalytic activity. So they attracted more and increasing attention as sensing materials for small biomolecules. This review focuses on the recent advances and strategies in the fabrication methods of 3D porous GR and the development of various electrochemical (bio)sensors based on porous GR and its nanocomposites for the detection of small biomolecules. The challenges and future efforts direction of high-performance electrochemical (bio)sensors based on 3D porous GR for more sensitive analysis of small biomolecules are discussed and proposed. It will give readers an overall understanding of their progress and provide some theoretical guidelines for their future efforts and development. Copyright © 2018 Elsevier B.V. All rights reserved.

The Clubbers' Guide: "Be Inspired, Inspire Others"

ERIC Educational Resources Information Center

Carter, Liz

2012-01-01

"Be inspired, inspire others" is this author's school motto and also something she aims to achieve by running the Science Club at The Warwick School in Redhill, Surrey, UK, an 11-16 specialist technology comprehensive. The Science Club is part of an extensive science, technology, engineering, and mathematics (STEM) programme that has…

Self-propelled swimming simulations of bio-inspired smart structures.

PubMed

Daghooghi, Mohsen; Borazjani, Iman

2016-08-09

This paper presents self-propelled swimming simulations of a foldable structure, whose folded configuration is a box. For self-locomotion through water the structure unfolds and undulates. To guide the design of the structure and understand how it should undulate to achieve either highest speed or maximize efficiency during locomotion, several kinematic parameters were systematically varied in the simulations: the wave type (standing wave versus traveling wave), the smoothness of undulations (smooth undulations versus undulations of rigid links), the mode of undulations (carangiform: mackerel-like versus anguilliform: eel-like undulations), and the maximum amplitude of undulations. We show that the swimmers with standing wave are slow and inefficient because they are not able to produce thrust using the added-mass mechanism. Among the tested types of undulation at low Reynolds number (Re) regime of [Formula: see text] (Strouhal number of about 1.0), structures that employ carangiform undulations can swim faster, whereas anguilliform swimmers are more economic, i.e., using less power they can swim a longer distance. Another finding of our simulations is that structures which are made of rigid links are typically less efficient (lower propulsive and power efficiencies and also lower swimming speed) compared with smoothly undulating ones because a higher added-mass force is generated by smooth undulations. The wake of all the swimmers bifurcated at the low Re regime because of the higher lateral relative to the axial velocity (high Strouhal number) that advects the vortices laterally creating a double row of vortices in the wake. In addition, we show that the wake cannot be used to predict the performance of the swimmers because the net force in each cycle is zero for self-propelled bodies and the pressure term is not negligible compared to the other terms.

High-speed detection of DNA translocation in nanopipettes.

PubMed

Fraccari, Raquel L; Ciccarella, Pietro; Bahrami, Azadeh; Carminati, Marco; Ferrari, Giorgio; Albrecht, Tim

2016-04-14

We present a high-speed electrical detection scheme based on a custom-designed CMOS amplifier which allows the analysis of DNA translocation in glass nanopipettes on a microsecond timescale. Translocation of different DNA lengths in KCl electrolyte provides a scaling factor of the DNA translocation time equal to p = 1.22, which is different from values observed previously with nanopipettes in LiCl electrolyte or with nanopores. Based on a theoretical model involving electrophoresis, hydrodynamics and surface friction, we show that the experimentally observed range of p-values may be the result of, or at least be affected by DNA adsorption and friction between the DNA and the substrate surface.

Bio-Photons of Various Cellular Cultures and Tissues

NASA Astrophysics Data System (ADS)

Hann, Patrick; Knoesel, Ernst; Garzon, Maria; Lofland, Samuel; Pfieffer, Erik

2008-04-01

Since it is non-invasive, there has been increased research in the field of bio-optics. Many biological systems display an unusual phenomenon, delayed luminescence, produced by what is known as bio-photons. We present an apparatus and procedure for the detection of these ultra-weak photonic emissions using a single photon detection device. The results of bread yeast, saccramyces, and algae will be presented and compared to other reports in the literature.

DNA-mounted self-assembly: new approaches for genomic analysis and SNP detection.

PubMed

Bichenkova, Elena V; Lang, Zhaolei; Yu, Xuan; Rogert, Candelaria; Douglas, Kenneth T

2011-01-01

This article presents an overview of new emerging approaches for nucleic acid detection via hybridization techniques that can potentially be applied to genomic analysis and SNP identification in clinical diagnostics. Despite the availability of a diverse variety of SNP genotyping technologies on the diagnostic market, none has truly succeeded in dominating its competitors thus far. Having been designed for specific diagnostic purposes or clinical applications, each of the existing bio-assay systems (briefly outlined here) is usually limited to a relatively narrow aspect or format of nucleic acid detection, and thus cannot entirely satisfy all the varieties of commercial requirements and clinical demands. This drives the diagnostic sector to pursue novel, cost-effective approaches to ensure rapid and reliable identification of pathogenic or hereditary human diseases. Hence, the purpose of this review is to highlight some new strategic directions in DNA detection technologies in order to inspire development of novel molecular diagnostic tools and bio-assay systems with superior reliability, reproducibility, robustness, accuracy and sensitivity at lower assay cost. One approach to improving the sensitivity of an assay to confidently discriminate between single point mutations is based on the use of target assembled, split-probe systems, which constitutes the main focus of this review. Copyright © 2010 Elsevier B.V. All rights reserved.

A smart magnetic nanoplatform for synergistic anticancer therapy: manoeuvring mussel-inspired functional magnetic nanoparticles for pH responsive anticancer drug delivery and hyperthermia

NASA Astrophysics Data System (ADS)

Sasikala, Arathyram Ramachandra Kurup; Ghavaminejad, Amin; Unnithan, Afeesh Rajan; Thomas, Reju George; Moon, Myeongju; Jeong, Yong Yeon; Park, Chan Hee; Kim, Cheol Sang

2015-10-01

We report the versatile design of a smart nanoplatform for thermo-chemotherapy treatment of cancer. For the first time in the literature, our design takes advantage of the outstanding properties of mussel-inspired multiple catecholic groups - presenting a unique copolymer poly(2-hydroxyethyl methacrylate-co-dopamine methacrylamide) p(HEMA-co-DMA) to surface functionalize the superparamagnetic iron oxide nanoparticles as well as to conjugate borate containing anticancer drug bortezomib (BTZ) in a pH-dependent manner for the synergistic anticancer treatment. The unique multiple anchoring groups can be used to substantially improve the affinity of the ligands to the surfaces of the nanoparticles to form ultrastable iron oxide nanoparticles with control over their hydrodynamic diameter and interfacial chemistry. Thus the BTZ-incorporated-bio-inspired-smart magnetic nanoplatform will act as a hyperthermic agent that delivers heat when an alternating magnetic field is applied while the BTZ-bound catechol moieties act as chemotherapeutic agents in a cancer environment by providing pH-dependent drug release for the synergistic thermo-chemotherapy application. The anticancer efficacy of these bio-inspired multifunctional smart magnetic nanoparticles was tested both in vitro and in vivo and found that these unique magnetic nanoplatforms can be established to endow for the next generation of nanomedicine for efficient and safe cancer therapy.We report the versatile design of a smart nanoplatform for thermo-chemotherapy treatment of cancer. For the first time in the literature, our design takes advantage of the outstanding properties of mussel-inspired multiple catecholic groups - presenting a unique copolymer poly(2-hydroxyethyl methacrylate-co-dopamine methacrylamide) p(HEMA-co-DMA) to surface functionalize the superparamagnetic iron oxide nanoparticles as well as to conjugate borate containing anticancer drug bortezomib (BTZ) in a pH-dependent manner for the synergistic

Fluorescence based explosive detection: from mechanisms to sensory materials.

PubMed

Sun, Xiangcheng; Wang, Ying; Lei, Yu

2015-11-21

The detection of explosives is one of the current pressing concerns in global security. In the past few decades, a large number of emissive sensing materials have been developed for the detection of explosives in vapor, solution, and solid states through fluorescence methods. In recent years, great efforts have been devoted to develop new fluorescent materials with various sensing mechanisms for detecting explosives in order to achieve super-sensitivity, ultra-selectivity, as well as fast response time. This review article starts with a brief introduction on various sensing mechanisms for fluorescence based explosive detection, and then summarizes in an exhaustive and systematic way the state-of-the-art of fluorescent materials for explosive detection with a focus on the research in the recent 5 years. A wide range of fluorescent materials, such as conjugated polymers, small fluorophores, supramolecular systems, bio-inspired materials and aggregation induced emission-active materials, and their sensing performance and sensing mechanism are the centerpiece of this review. Finally, conclusions and future outlook are presented and discussed.

Effect of chewing speed on the detection of a foreign object in food.

PubMed

Paphangkorakit, J; Ladsena, V; Rukyuttithamkul, T; Khamtad, T

2016-03-01

Accidentally biting hard on a piece of hard foreign object in food is among the causes of tooth fracturing and could be associated with oral sensibility. This study has investigated the effect of chewing speed on the ability to detect a foreign object in food in human. Fourteen healthy subjects were asked to randomly chew one of 10 cooked rice balls, five of which containing a foreign object made from a tiny uncooked rice grain, until they detected the rice grain. Each subject chewed the test foods both at 50 (slow) and 100 (fast) chews min(-1). The accuracy of detection and the number of chews before detection (CBD) were recorded and compared between the two chewing speeds using paired t-tests. The results showed that almost all subjects detected the foreign object by biting. The accuracy of detection was more than 90% and not significantly different between slow and fast chewing but the mean CBD in slow chewing (11·7 ± 1·3 chews) was significantly different from that in fast chewing (20·7 ± 1·9 chews; P < 0·001). The study showed that slow chewers required less number of chews before a foreign object in food could be detected and was, presumably, more effective in detecting the object compared to fast chewers. If each chew bears equal probability of teeth encountering the foreign object, slow chewing might also reduce the chance of accidentally biting hard on the foreign object and fracturing the tooth. © 2015 John Wiley & Sons Ltd.

Flow Interactions of Two- and Three-Dimensional Networked Bio-Inspired Control Elements in an In-Line Arrangement.

PubMed

Kurt, Melike; Moored, Keith

2018-04-19

-dimensions. These results can aid in the design of networked bio-inspired control elements that through integrated sensing can synchronize to three-dimensional flow interactions. © 2018 IOP Publishing Ltd.

Lowering thresholds for speed limit enforcement impairs peripheral object detection and increases driver subjective workload.

PubMed

Bowden, Vanessa K; Loft, Shayne; Tatasciore, Monica; Visser, Troy A W

2017-01-01

Speed enforcement reduces incidences of speeding, thus reducing traffic accidents. Accordingly, it has been argued that stricter speed enforcement thresholds could further improve road safety. Effective speed monitoring however requires driver attention and effort, and human information-processing capacity is limited. Emphasizing speed monitoring may therefore reduce resource availability for other aspects of safe vehicle operation. We investigated whether lowering enforcement thresholds in a simulator setting would introduce further competition for limited cognitive and visual resources. Eighty-four young adult participants drove under conditions where they could be fined for travelling 1, 6, or 11km/h over a 50km/h speed-limit. Stricter speed enforcement led to greater subjective workload and significant decrements in peripheral object detection. These data indicate that the benefits of reduced speeding with stricter enforcement may be at least partially offset by greater mental demands on drivers, reducing their responses to safety-critical stimuli on the road. It is likely these results under-estimate the impact of stricter speed enforcement on real-world drivers who experience significantly greater pressures to drive at or above the speed limit. Copyright © 2016 Elsevier Ltd. All rights reserved.

Performance of the BioPlex 2200 HIV Ag-Ab assay for identifying acute HIV infection.

PubMed

Eshleman, Susan H; Piwowar-Manning, Estelle; Sivay, Mariya V; Debevec, Barbara; Veater, Stephanie; McKinstry, Laura; Bekker, Linda-Gail; Mannheimer, Sharon; Grant, Robert M; Chesney, Margaret A; Coates, Thomas J; Koblin, Beryl A; Fogel, Jessica M

Assays that detect HIV antigen (Ag) and antibody (Ab) can be used to screen for HIV infection. To compare the performance of the BioPlex 2200 HIV Ag-Ab assay and two other Ag/Ab combination assays for detection of acute HIV infection. Samples were obtained from 24 individuals (18 from the US, 6 from South Africa); these individuals were classified as having acute infection based on the following criteria: positive qualitative RNA assay; two negative rapid tests; negative discriminatory test. The samples were tested with the BioPlex assay, the ARCHITECT HIV Ag/Ab Combo test, the Bio-Rad GS HIV Combo Ag-Ab EIA test, and a viral load assay. Twelve (50.0%) of 24 samples had RNA detected only ( > 40 to 13,476 copies/mL). Ten (43.5%) samples had reactive results with all three Ag/Ab assays, one sample was reactive with the ARCHITECT and Bio-Rad assays, and one sample was reactive with the Bio-Rad and BioPlex assays. The 11 samples that were reactive with the BioPlex assay had viral loads from 83,010 to >750,000 copies/mL; 9/11 samples were classified as Ag positive/Ab negative by the BioPlex assay. Detection of acute HIV infection was similar for the BioPlex assay and two other Ag/Ab assays. All three tests were less sensitive than a qualitative RNA assay and only detected HIV Ag when the viral load was high. The BioPlex assay detected acute infection in about half of the cases, and identified most of those infections as Ag positive/Ab negative. Copyright © 2018 Elsevier B.V. All rights reserved.

Time-Gated Orthogonal Scanning Automated Microscopy (OSAM) for High-speed Cell Detection and Analysis

NASA Astrophysics Data System (ADS)

Lu, Yiqing; Xi, Peng; Piper, James A.; Huo, Yujing; Jin, Dayong

2012-11-01

We report a new development of orthogonal scanning automated microscopy (OSAM) incorporating time-gated detection to locate rare-event organisms regardless of autofluorescent background. The necessity of using long-lifetime (hundreds of microseconds) luminescent biolabels for time-gated detection implies long integration (dwell) time, resulting in slow scan speed. However, here we achieve high scan speed using a new 2-step orthogonal scanning strategy to realise on-the-fly time-gated detection and precise location of 1-μm lanthanide-doped microspheres with signal-to-background ratio of 8.9. This enables analysis of a 15 mm × 15 mm slide area in only 3.3 minutes. We demonstrate that detection of only a few hundred photoelectrons within 100 μs is sufficient to distinguish a target event in a prototype system using ultraviolet LED excitation. Cytometric analysis of lanthanide labelled Giardia cysts achieved a signal-to-background ratio of two orders of magnitude. Results suggest that time-gated OSAM represents a new opportunity for high-throughput background-free biosensing applications.

An optical system for detecting 3D high-speed oscillation of a single ultrasound microbubble

PubMed Central

Liu, Yuan; Yuan, Baohong

2013-01-01

As contrast agents, microbubbles have been playing significant roles in ultrasound imaging. Investigation of microbubble oscillation is crucial for microbubble characterization and detection. Unfortunately, 3-dimensional (3D) observation of microbubble oscillation is challenging and costly because of the bubble size—a few microns in diameter—and the high-speed dynamics under MHz ultrasound pressure waves. In this study, a cost-efficient optical confocal microscopic system combined with a gated and intensified charge-coupled device (ICCD) camera were developed to detect 3D microbubble oscillation. The capability of imaging microbubble high-speed oscillation with much lower costs than with an ultra-fast framing or streak camera system was demonstrated. In addition, microbubble oscillations along both lateral (x and y) and axial (z) directions were demonstrated. Accordingly, this system is an excellent alternative for 3D investigation of microbubble high-speed oscillation, especially when budgets are limited. PMID:24049677

Neutrophil-inspired propulsion in a combined acoustic and magnetic field.

PubMed

Ahmed, Daniel; Baasch, Thierry; Blondel, Nicolas; Läubli, Nino; Dual, Jürg; Nelson, Bradley J

2017-10-03

Systems capable of precise motion in the vasculature can offer exciting possibilities for applications in targeted therapeutics and non-invasive surgery. So far, the majority of the work analysed propulsion in a two-dimensional setting with limited controllability near boundaries. Here we show bio-inspired rolling motion by introducing superparamagnetic particles in magnetic and acoustic fields, inspired by a neutrophil rolling on a wall. The particles self-assemble due to dipole-dipole interaction in the presence of a rotating magnetic field. The aggregate migrates towards the wall of the channel due to the radiation force of an acoustic field. By combining both fields, we achieved a rolling-type motion along the boundaries. The use of both acoustic and magnetic fields has matured in clinical settings. The combination of both fields is capable of overcoming the limitations encountered by single actuation techniques. We believe our method will have far-reaching implications in targeted therapeutics.Devising effective swimming and propulsion strategies in microenvironments is attractive for drug delivery applications. Here Ahmed et al. demonstrate a micropropulsion strategy in which a combination of magnetic and acoustic fields is used to assemble and propel colloidal particles along channel walls.

Jump stabilization and landing control by wing-spreading of a locust-inspired jumper.

PubMed

Beck, Avishai; Zaitsev, Valentin; Hanan, Uri Ben; Kosa, Gabor; Ayali, Amir; Weiss, Avi

2017-10-16

Bio-inspired robotics is a promising design strategy for mobile robots. Jumping is an energy efficient locomotion gait for traversing difficult terrain. Inspired by the jumping and flying behavior of the desert locust, we have recently developed a miniature jumping robot that can jump over 3.5 m high. However, much like the non-adult locust, it rotates while in the air and lands uncontrollably. Inspired by the winged adult locust, we have added spreading wings and a tail to the jumper. After the robot leaps, at the apex of the trajectory, the wings unfold and it glides to the ground. The advantages of this maneuver are the stabilization of the robot when airborne, the reduction of velocity at landing, the control of the landing angle and the potential to change the robot's orientation and control its flight trajectory. The new upgraded robot is capable of jumping to a still impressive height of 1.7 m eliminating airborne rotation and reducing landing velocity. Here, we analyze the dynamic and aerodynamic models of the robot, discuss the robot's design, and validate its ability to perform a jump-glide in a stable trajectory, land safely and change its orientation while in the air.

Design of a Fatigue Detection System for High-Speed Trains Based on Driver Vigilance Using a Wireless Wearable EEG.

PubMed

Zhang, Xiaoliang; Li, Jiali; Liu, Yugang; Zhang, Zutao; Wang, Zhuojun; Luo, Dianyuan; Zhou, Xiang; Zhu, Miankuan; Salman, Waleed; Hu, Guangdi; Wang, Chunbai

2017-03-01

The vigilance of the driver is important for railway safety, despite not being included in the safety management system (SMS) for high-speed train safety. In this paper, a novel fatigue detection system for high-speed train safety based on monitoring train driver vigilance using a wireless wearable electroencephalograph (EEG) is presented. This system is designed to detect whether the driver is drowsiness. The proposed system consists of three main parts: (1) a wireless wearable EEG collection; (2) train driver vigilance detection; and (3) early warning device for train driver. In the first part, an 8-channel wireless wearable brain-computer interface (BCI) device acquires the locomotive driver's brain EEG signal comfortably under high-speed train-driving conditions. The recorded data are transmitted to a personal computer (PC) via Bluetooth. In the second step, a support vector machine (SVM) classification algorithm is implemented to determine the vigilance level using the Fast Fourier transform (FFT) to extract the EEG power spectrum density (PSD). In addition, an early warning device begins to work if fatigue is detected. The simulation and test results demonstrate the feasibility of the proposed fatigue detection system for high-speed train safety.

Design of a Fatigue Detection System for High-Speed Trains Based on Driver Vigilance Using a Wireless Wearable EEG

PubMed Central

Zhang, Xiaoliang; Li, Jiali; Liu, Yugang; Zhang, Zutao; Wang, Zhuojun; Luo, Dianyuan; Zhou, Xiang; Zhu, Miankuan; Salman, Waleed; Hu, Guangdi; Wang, Chunbai

2017-01-01

The vigilance of the driver is important for railway safety, despite not being included in the safety management system (SMS) for high-speed train safety. In this paper, a novel fatigue detection system for high-speed train safety based on monitoring train driver vigilance using a wireless wearable electroencephalograph (EEG) is presented. This system is designed to detect whether the driver is drowsiness. The proposed system consists of three main parts: (1) a wireless wearable EEG collection; (2) train driver vigilance detection; and (3) early warning device for train driver. In the first part, an 8-channel wireless wearable brain-computer interface (BCI) device acquires the locomotive driver’s brain EEG signal comfortably under high-speed train-driving conditions. The recorded data are transmitted to a personal computer (PC) via Bluetooth. In the second step, a support vector machine (SVM) classification algorithm is implemented to determine the vigilance level using the Fast Fourier transform (FFT) to extract the EEG power spectrum density (PSD). In addition, an early warning device begins to work if fatigue is detected. The simulation and test results demonstrate the feasibility of the proposed fatigue detection system for high-speed train safety. PMID:28257073

Robust Models for Optic Flow Coding in Natural Scenes Inspired by Insect Biology

PubMed Central

Brinkworth, Russell S. A.; O'Carroll, David C.

2009-01-01

The extraction of accurate self-motion information from the visual world is a difficult problem that has been solved very efficiently by biological organisms utilizing non-linear processing. Previous bio-inspired models for motion detection based on a correlation mechanism have been dogged by issues that arise from their sensitivity to undesired properties of the image, such as contrast, which vary widely between images. Here we present a model with multiple levels of non-linear dynamic adaptive components based directly on the known or suspected responses of neurons within the visual motion pathway of the fly brain. By testing the model under realistic high-dynamic range conditions we show that the addition of these elements makes the motion detection model robust across a large variety of images, velocities and accelerations. Furthermore the performance of the entire system is more than the incremental improvements offered by the individual components, indicating beneficial non-linear interactions between processing stages. The algorithms underlying the model can be implemented in either digital or analog hardware, including neuromorphic analog VLSI, but defy an analytical solution due to their dynamic non-linear operation. The successful application of this algorithm has applications in the development of miniature autonomous systems in defense and civilian roles, including robotics, miniature unmanned aerial vehicles and collision avoidance sensors. PMID:19893631

The Inspirational Leader

ERIC Educational Resources Information Center

Benigni, Mark D.; Hughes, Mark A

2012-01-01

Amid the focus on improved standardized test scores, differentiated instruction, value-added initiatives and improved teacher evaluation, one must not ignore an education leader's need to inspire and be inspired. But how do education leaders inspire their students and teachers during some of the most difficult economic times the nation has ever…

Surface regions of illusory images are detected with a slower processing speed than those of luminance-defined images.

PubMed

Mihaylova, Milena; Manahilov, Velitchko

2010-11-24

Research has shown that the processing time for discriminating illusory contours is longer than for real contours. We know, however, little whether the visual processes, associated with detecting regions of illusory surfaces, are also slower as those responsible for detecting luminance-defined images. Using a speed-accuracy trade-off (SAT) procedure, we measured accuracy as a function of processing time for detecting illusory Kanizsa-type and luminance-defined squares embedded in 2D static luminance noise. The data revealed that the illusory images were detected at slower processing speed than the real images, while the points in time, when accuracy departed from chance, were not significantly different for both stimuli. The classification images for detecting illusory and real squares showed that observers employed similar detection strategies using surface regions of the real and illusory squares. The lack of significant differences between the x-intercepts of the SAT functions for illusory and luminance-modulated stimuli suggests that the detection of surface regions of both images could be based on activation of a single mechanism (the dorsal magnocellular visual pathway). The slower speed for detecting illusory images as compared to luminance-defined images could be attributed to slower processes of filling-in of regions of illusory images within the dorsal pathway.

Highly Stable Lyophilized Homogeneous Bead-Based Immunoassays for On-Site Detection of Bio Warfare Agents from Complex Matrices.

PubMed

Mechaly, Adva; Marx, Sharon; Levy, Orly; Yitzhaki, Shmuel; Fisher, Morly

2016-06-21

This study shows the development of dry, highly stable immunoassays for the detection of bio warfare agents in complex matrices. Thermal stability was achieved by the lyophilization of the complete, homogeneous, bead-based immunoassay in a special stabilizing buffer, resulting in a ready-to-use, simple assay, which exhibited long shelf and high-temperature endurance (up to 1 week at 100 °C). The developed methodology was successfully implemented for the preservation of time-resolved fluorescence, Alexa-fluorophores, and horse radish peroxidase-based bead assays, enabling multiplexed detection. The multiplexed assay was successfully implemented for the detection of Bacillus anthracis, botulinum B, and tularemia in complex matrices.

Bio-sensing with butterfly wings: naturally occurring nano-structures for SERS-based malaria parasite detection.

PubMed

Garrett, Natalie L; Sekine, Ryo; Dixon, Matthew W A; Tilley, Leann; Bambery, Keith R; Wood, Bayden R

2015-09-07

Surface enhanced Raman scattering (SERS) is a powerful tool with great potential to provide improved bio-sensing capabilities. The current 'gold-standard' method for diagnosis of malaria involves visual inspection of blood smears using light microscopy, which is time consuming and can prevent early diagnosis of the disease. We present a novel surface-enhanced Raman spectroscopy substrate based on gold-coated butterfly wings, which enabled detection of malarial hemozoin pigment within lysed blood samples containing 0.005% and 0.0005% infected red blood cells.

Sky light polarization detection with linear polarizer triplet in light field camera inspired by insect vision.

PubMed

Zhang, Wenjing; Cao, Yu; Zhang, Xuanzhe; Liu, Zejin

2015-10-20

Stable information of a sky light polarization pattern can be used for navigation with various advantages such as better performance of anti-interference, no "error cumulative effect," and so on. But the existing method of sky light polarization measurement is weak in real-time performance or with a complex system. Inspired by the navigational capability of a Cataglyphis with its compound eyes, we introduce a new approach to acquire the all-sky image under different polarization directions with one camera and without a rotating polarizer, so as to detect the polarization pattern across the full sky in a single snapshot. Our system is based on a handheld light field camera with a wide-angle lens and a triplet linear polarizer placed over its aperture stop. Experimental results agree with the theoretical predictions. Not only real-time detection but simple and costless architecture demonstrates the superiority of the approach proposed in this paper.

A bio-inspired swellable microneedle adhesive for mechanical interlocking with tissue

NASA Astrophysics Data System (ADS)

Yang, Seung Yun; O'Cearbhaill, Eoin D.; Sisk, Geoffroy C.; Park, Kyeng Min; Cho, Woo Kyung; Villiger, Martin; Bouma, Brett E.; Pomahac, Bohdan; Karp, Jeffrey M.

2013-04-01

Achieving significant adhesion to soft tissues while minimizing tissue damage poses a considerable clinical challenge. Chemical-based adhesives require tissue-specific reactive chemistry, typically inducing a significant inflammatory response. Staples are fraught with limitations including high-localized tissue stress and increased risk of infection, and nerve and blood vessel damage. Here inspired by the endoparasite Pomphorhynchus laevis, which swells its proboscis to attach to its host’s intestinal wall, we have developed a biphasic microneedle array that mechanically interlocks with tissue through swellable microneedle tips, achieving ~3.5-fold increase in adhesion strength compared with staples in skin graft fixation, and removal force of ~4.5 N cm-2 from intestinal mucosal tissue. Comprising a poly(styrene)-block-poly(acrylic acid) swellable tip and non-swellable polystyrene core, conical microneedles penetrate tissue with minimal insertion force and depth, yet high adhesion strength in their swollen state. Uniquely, this design provides universal soft tissue adhesion with minimal damage, less traumatic removal, reduced risk of infection and delivery of bioactive therapeutics.

A Bio-Inspired Swellable Microneedle Adhesive for Mechanical Interlocking with Tissue

PubMed Central

Yang, Seung Yun; O'Cearbhaill, Eoin D.; Sisk, Geoffroy C.; Park, Kyeng Min; Cho, Woo Kyung; Villiger, Martin; Bouma, Brett E.; Pomahac, Bohdan; Karp, Jeffrey M.

2013-01-01

Achieving significant adhesion to soft tissues while minimizing tissue damage poses a considerable clinical challenge. Chemical-based adhesives require tissue-specific reactive chemistry, typically inducing a significant inflammatory response. Staples are fraught with limitations including high-localized tissue stress and increased risk of infection, and nerve and blood vessel damage. Here, inspired by the endoparasite Pomphorhynchus laevis which swells its proboscis to attach to its host’s intestinal wall, we have developed a biphasic microneedle array that mechanically interlocks with tissue through swellable microneedle tips, achieving ~ 3.5 fold increase in adhesion strength compared to staples in skin graft fixation, and removal force of ~ 4.5 N/cm2 from intestinal mucosal tissue. Comprising a poly(styrene)-block-poly(acrylic acid) swellable tip and non-swellable polystyrene core, conical microneedles penetrate tissue with minimal insertion force and depth, yet high adhesion strength in their swollen state. Uniquely, this design provides universal soft tissue adhesion with minimal damage, less traumatic removal, reduced risk of infection and delivery of bioactive therapeutics. PMID:23591869

Laser-Sintered Constructs with Bio-inspired Porosity and Surface Micro/Nano-Roughness Enhance Mesenchymal Stem Cell Differentiation and Matrix Mineralization In Vitro.

PubMed

Cheng, Alice; Cohen, David J; Boyan, Barbara D; Schwartz, Zvi

2016-12-01

Direct metal laser sintering can produce porous Ti-6Al-4V orthopedic and dental implants. The process requires reduced resources and time and can provide greater structural control than machine manufacturing. Implants in bone are colonized by mesenchymal stem cells (MSCs), which can differentiate into osteoblasts and contribute to osseointegration. This study examined osteoblast differentiation and matrix mineralization of human MSCs cultured on laser-sintered Ti-6Al-4V constructs with varying porosity and at different time scales. 2D solid disks and low, medium and high porosity (LP, MP, and HP) 3D constructs based on a human trabecular bone template were laser sintered from Ti-6Al-4V powder and further processed to have micro- and nanoscale roughness. hMSCs exhibited greater osteoblastic differentiation and local factor production on all 3D porous constructs compared to 2D surfaces, which was sustained for 9 days without use of exogenous factors. hMSCs cultured for 8 weeks on MP constructs in osteogenic medium (OM), OM supplemented with BMP2 or collagen-coated MP constructs in OM exhibited bone-like extracellular matrix mineralization. Use of bio-inspired porosity for the 3D architecture of additively manufactured Ti-6Al-4V enhanced osteogenic differentiation of hMSCs beyond surface roughness alone. This study suggests that a 3D architecture may enhance the osseointegration of orthopedic and dental implants in vivo.

High-Speed Observer: Automated Streak Detection in SSME Plumes

NASA Technical Reports Server (NTRS)

Rieckoff, T. J.; Covan, M.; OFarrell, J. M.

2001-01-01

A high frame rate digital video camera installed on test stands at Stennis Space Center has been used to capture images of Space Shuttle main engine plumes during test. These plume images are processed in real time to detect and differentiate anomalous plume events occurring during a time interval on the order of 5 msec. Such speed yields near instantaneous availability of information concerning the state of the hardware. This information can be monitored by the test conductor or by other computer systems, such as the integrated health monitoring system processors, for possible test shutdown before occurrence of a catastrophic engine failure.

Self-cleaning antimicrobial surfaces by bio-enabled growth of SnO2 coatings on glass

NASA Astrophysics Data System (ADS)

André, Rute; Natalio, Filipe; Tahir, Muhammad Nawaz; Berger, Rüdiger; Tremel, Wolfgang

2013-03-01

Conventional vapor-deposition techniques for coatings require sophisticated equipment and/or high-temperature resistant substrates. Therefore bio-inspired techniques for the fabrication of inorganic coatings have been developed in recent years. Inspired by the biology behind the formation of the intricate skeletons of diatoms orchestrated by a class of cationic polyamines (silaffins) we have used surface-bound spermine, a naturally occurring polyamine, to promote the fast deposition of homogeneous, thin and transparent biomimetic SnO2 coatings on glass surfaces. The bio-enabled SnO2 film is highly photoactive, i.e. it generates superoxide radicals (O2&z.rad;-) upon sunlight exposure resulting in a strong degradation of organic contaminants and a strong antimicrobial activity. Upon illumination the biomimetic SnO2 coating exhibits a switchable amphiphilic behavior, which - in combination with its photoactivity - creates a self-cleaning surface. The intrinsic self-cleaning properties could lead to the development of new protective, antifouling coatings on various substrates.Conventional vapor-deposition techniques for coatings require sophisticated equipment and/or high-temperature resistant substrates. Therefore bio-inspired techniques for the fabrication of inorganic coatings have been developed in recent years. Inspired by the biology behind the formation of the intricate skeletons of diatoms orchestrated by a class of cationic polyamines (silaffins) we have used surface-bound spermine, a naturally occurring polyamine, to promote the fast deposition of homogeneous, thin and transparent biomimetic SnO2 coatings on glass surfaces. The bio-enabled SnO2 film is highly photoactive, i.e. it generates superoxide radicals (O2&z.rad;-) upon sunlight exposure resulting in a strong degradation of organic contaminants and a strong antimicrobial activity. Upon illumination the biomimetic SnO2 coating exhibits a switchable amphiphilic behavior, which - in combination with its

Characterization and prediction of the backscattered form function of an immersed cylindrical shell using hybrid fuzzy clustering and bio-inspired algorithms.

PubMed

Agounad, Said; Aassif, El Houcein; Khandouch, Younes; Maze, Gérard; Décultot, Dominique

2018-02-01

The acoustic scattering of a plane wave by an elastic cylindrical shell is studied. A new approach is developed to predict the form function of an immersed cylindrical shell of the radius ratio b/a ('b' is the inner radius and 'a' is the outer radius). The prediction of the backscattered form function is investigated by a combined approach between fuzzy clustering algorithms and bio-inspired algorithms. Four famous fuzzy clustering algorithms: the fuzzy c-means (FCM), the Gustafson-Kessel algorithm (GK), the fuzzy c-regression model (FCRM) and the Gath-Geva algorithm (GG) are combined with particle swarm optimization and genetic algorithm. The symmetric and antisymmetric circumferential waves A, S 0 , A 1 , S 1 and S 2 are investigated in a reduced frequency (k 1 a) range extends over 0.1

Sensorless speed detection of squirrel-cage induction machines using stator neutral point voltage harmonics

NASA Astrophysics Data System (ADS)

Petrovic, Goran; Kilic, Tomislav; Terzic, Bozo

2009-04-01

In this paper a sensorless speed detection method of induction squirrel-cage machines is presented. This method is based on frequency determination of the stator neutral point voltage primary slot harmonic, which is dependent on rotor speed. In order to prove method in steady state and dynamic conditions the simulation and experimental study was carried out. For theoretical investigation the mathematical model of squirrel cage induction machines, which takes into consideration actual geometry and windings layout, is used. Speed-related harmonics that arise from rotor slotting are analyzed using digital signal processing and DFT algorithm with Hanning window. The performance of the method is demonstrated over a wide range of load conditions.

BioSentinel: Developing a Space Radiation Biosensor

NASA Technical Reports Server (NTRS)

Santa Maria, Sergio R.

2015-01-01

BioSentinel is an autonomous fully self-contained science mission that will conduct the first study of the biological response to space radiation outside low Earth orbit (LEO) in over 40 years. The 4-unit (4U) BioSentinel biosensor system, is housed within a 6-Unit (6U) spacecraft, and uses yeast cells in multiple independent microfluidic cards to detect and measure DNA damage that occurs in response to ambient space radiation. Cell growth and metabolic activity will be measured using a 3-color LED detection system and a metabolic indicator dye with a dedicated thermal control system per fluidic card.

Feature extraction inspired by V1 in visual cortex

NASA Astrophysics Data System (ADS)

Lv, Chao; Xu, Yuelei; Zhang, Xulei; Ma, Shiping; Li, Shuai; Xin, Peng; Zhu, Mingning; Ma, Hongqiang

2018-04-01

Target feature extraction plays an important role in pattern recognition. It is the most complicated activity in the brain mechanism of biological vision. Inspired by high properties of primary visual cortex (V1) in extracting dynamic and static features, a visual perception model was raised. Firstly, 28 spatial-temporal filters with different orientations, half-squaring operation and divisive normalization were adopted to obtain the responses of V1 simple cells; then, an adjustable parameter was added to the output weight so that the response of complex cells was got. Experimental results indicate that the proposed V1 model can perceive motion information well. Besides, it has a good edge detection capability. The model inspired by V1 has good performance in feature extraction and effectively combines brain-inspired intelligence with computer vision.

Induced Ellipticity for Inspiraling Binary Systems

NASA Astrophysics Data System (ADS)

Randall, Lisa; Xianyu, Zhong-Zhi

2018-01-01

Although gravitational waves tend to erase eccentricity of an inspiraling binary system, ellipticity can be generated in the presence of surrounding matter. We present a semianalytical method for understanding the eccentricity distribution of binary black holes (BHs) in the presence of a supermassive BH in a galactic center. Given a matter distribution, we show how to determine the resultant eccentricity analytically in the presence of both tidal forces and evaporation up to one cutoff and one matter-distribution-independent function, paving the way for understanding the environment of detected inspiraling BHs. We furthermore generalize Kozai–Lidov dynamics to situations where perturbation theory breaks down for short time intervals, allowing more general angular momentum exchange, such that eccentricity is generated even when all bodies orbit in the same plane.

Mastering multi-depth bio-chip patterns with DVD LBRs

NASA Astrophysics Data System (ADS)

Carson, Doug

2017-08-01

Bio chip and bio disc are rapidly growing technologies used in medical, health and other industries. While there are numerous unique designs and features, these products all rely on precise three-dimensional micro-fluidic channels or arrays to move, separate and combine samples under test. These bio chip and bio disc consumables are typically manufactured by molding these parts to a precise three-dimensional pattern on a negative metal stamper, or they can be made in smaller quantities using an appropriate curable resin and a negative mold/stamper. Stampers required for bio chips have been traditionally made using either micro machining or XY stepping lithography. Both of these technologies have their advantages as well as limitations when it comes to creating micro-fluidic patterns. Significant breakthroughs in continuous maskless lithography have enabled accurate and efficient manufacturing of micro-fluidic masters using LBRs (Laser Beam Recorders) and DRIE (Deep Reactive Ion Etching). The important advantages of LBR continuous lithography vs. XY stepping lithography and micro machining are speed and cost. LBR based continuous lithography is >100x faster than XY stepping lithography and more accurate than micro machining. Several innovations were required in order to create multi-depth patterns with sub micron accuracy. By combining proven industrial LBRs with DCA's G3-VIA pattern generator and DRIE, three-dimensional bio chip masters and stampers are being manufactured efficiently and accurately.

Measuring (bio)physical tree properties using accelerometers

NASA Astrophysics Data System (ADS)

van Emmerik, Tim; Steele-Dunne, Susan; Hut, Rolf; Gentine, Pierre; Selker, John; van de Giesen, Nick

2017-04-01

Trees play a crucial role in the water, carbon and nitrogen cycle on local, regional and global scales. Understanding the exchange of heat, water, and CO2 between trees and the atmosphere is important to assess the impact of drought, deforestation and climate change. Unfortunately, ground measurements of tree dynamics are often expensive, or difficult due to challenging environments. We demonstrate the potential of measuring (bio)physical properties of trees using robust and affordable acceleration sensors. Tree sway is dependent on e.g. mass and wind energy absorption of the tree. By measuring tree acceleration we can relate the tree motion to external loads (e.g. precipitation), and tree (bio)physical properties (e.g. mass). Using five months of acceleration data of 19 trees in the Brazilian Amazon, we show that the frequency spectrum of tree sway is related to mass, precipitation, and canopy drag. This presentation aims to show the concept of using accelerometers to measure tree dynamics, and we acknowledge that the presented example applications is not an exhaustive list. Further analyses are the scope of current research, and we hope to inspire others to explore additional applications.

Physicists Get INSPIREd: INSPIRE Project and Grid Applications

NASA Astrophysics Data System (ADS)

Klem, Jukka; Iwaszkiewicz, Jan

2011-12-01

INSPIRE is the new high-energy physics scientific information system developed by CERN, DESY, Fermilab and SLAC. INSPIRE combines the curated and trusted contents of SPIRES database with Invenio digital library technology. INSPIRE contains the entire HEP literature with about one million records and in addition to becoming the reference HEP scientific information platform, it aims to provide new kinds of data mining services and metrics to assess the impact of articles and authors. Grid and cloud computing provide new opportunities to offer better services in areas that require large CPU and storage resources including document Optical Character Recognition (OCR) processing, full-text indexing of articles and improved metrics. D4Science-II is a European project that develops and operates an e-Infrastructure supporting Virtual Research Environments (VREs). It develops an enabling technology (gCube) which implements a mechanism for facilitating the interoperation of its e-Infrastructure with other autonomously running data e-Infrastructures. As a result, this creates the core of an e-Infrastructure ecosystem. INSPIRE is one of the e-Infrastructures participating in D4Science-II project. In the context of the D4Science-II project, the INSPIRE e-Infrastructure makes available some of its resources and services to other members of the resulting ecosystem. Moreover, it benefits from the ecosystem via a dedicated Virtual Organization giving access to an array of resources ranging from computing and storage resources of grid infrastructures to data and services.

Detection of bio-signature by microscopy and mass spectrometry

NASA Astrophysics Data System (ADS)

Tulej, M.; Wiesendanger, R.; Neuland, M., B.; Meyer, S.; Wurz, P.; Neubeck, A.; Ivarsson, M.; Riedo, V.; Moreno-Garcia, P.; Riedo, A.; Knopp, G.

2017-09-01

We demonstrate detection of micro-sized fossilized bacteria by means of microscopy and mass spectrometry. The characteristic structures of lifelike forms are visualized with a micrometre spatial resolution and mass spectrometric analyses deliver elemental and isotope composition of host and fossilized materials. Our studies show that high selectivity in isolation of fossilized material from host phase can be achieved while applying a microscope visualization (location), a laser ablation ion source with sufficiently small laser spot size and applying depth profiling method. Our investigations shows that fossilized features can be well isolated from host phase. The mass spectrometric measurements can be conducted with sufficiently high accuracy and precision yielding quantitative elemental and isotope composition of micro-sized objects. The current performance of the instrument allows the measurement of the isotope fractionation in per mill level and yield exclusively definition of the origin of the investigated species by combining optical visualization of investigated samples (morphology and texture), chemical characterization of host and embedded in the host micro-sized structure. Our isotope analyses involved bio-relevant B, C, S, and Ni isotopes which could be measured with sufficiently accuracy to conclude about the nature of the micro-sized objects.

Serological Diagnosis of Acute Scrub Typhus in Southern India: Evaluation of InBios Scrub Typhus Detect IgM Rapid Test and Comparison with other Serological Tests.

PubMed

Anitharaj, Velmurugan; Stephen, Selvaraj; Pradeep, Jothimani; Park, Sungman; Kim, Seung-Han; Kim, Young Jin; Kim, Eun-Ye; Kim, Yoon-Won

2016-11-01

Scrub Typhus (ST) is being reported from different parts of India in the recent past. However, the diagnosis and confirmation of ST cases require specific serological and molecular diagnostic tests. Both rapid and conventional ELISA tests need to be properly evaluated. Evaluation of a new ST IgM Immunochromatography (ICT) test kit (InBios Scrub Typhus Detect IgM Rapid Test) and compare it with another rapid kit, conventional ELISA kit and Weil-Felix (WF) test. This prospective study was carried out in Mahatma Gandhi Medical College and Research Institute, Puducherry, during November 2015 to June 2016. Clinically suspected 220 ST patients were examined by a new kit, InBios Scrub Typhus Detect IgM Rapid Test, taking the conventional InBios Scrub Typhus Detect IgM ELISA as reference. Additional comparison was made with ImmuneMed Scrub Typhus Rapid, and WF test (single OXK titers ≥1:320). Statistical analysis was performed (Chi-square, Spearman's correlation and Kappa) using IBM SPSS Statistics 17 for Windows (SPSS Inc; Chicago, USA). Percentage Sensitivity, Specificity, Positive Predictive and Negative Predictive Values for InBios, ImmuneMed and WF were 99.25, 93.02, 95.68, 98.77; 94.87, 94.19, 96.21, 92.05 and 50.38, 95.51, 94.29, 56.67 respectively. A total of 134 patients were positive in reference standard InBios IgM ELISA. This new rapid ST IgM kit validated for the first time in India, showed good sensitivity and specificity. As a Point-of-Care (PoC) test, the kit would be helpful in both urban and remote rural parts of India.

Serological Diagnosis of Acute Scrub Typhus in Southern India: Evaluation of InBios Scrub Typhus Detect IgM Rapid Test and Comparison with other Serological Tests

PubMed Central

Anitharaj, Velmurugan; Pradeep, Jothimani; Park, Sungman; Kim, Seung-Han; Kim, Young Jin; Kim, Eun-Ye; Kim, Yoon-Won

2016-01-01

Introduction Scrub Typhus (ST) is being reported from different parts of India in the recent past. However, the diagnosis and confirmation of ST cases require specific serological and molecular diagnostic tests. Both rapid and conventional ELISA tests need to be properly evaluated. Aim Evaluation of a new ST IgM Immunochromatography (ICT) test kit (InBios Scrub Typhus Detect IgM Rapid Test) and compare it with another rapid kit, conventional ELISA kit and Weil-Felix (WF) test. Materials and Methods This prospective study was carried out in Mahatma Gandhi Medical College and Research Institute, Puducherry, during November 2015 to June 2016. Clinically suspected 220 ST patients were examined by a new kit, InBios Scrub Typhus Detect IgM Rapid Test, taking the conventional InBios Scrub Typhus Detect IgM ELISA as reference. Additional comparison was made with ImmuneMed Scrub Typhus Rapid, and WF test (single OXK titers ≥1:320). Statistical analysis was performed (Chi-square, Spearman’s correlation and Kappa) using IBM SPSS Statistics 17 for Windows (SPSS Inc; Chicago, USA). Results Percentage Sensitivity, Specificity, Positive Predictive and Negative Predictive Values for InBios, ImmuneMed and WF were 99.25, 93.02, 95.68, 98.77; 94.87, 94.19, 96.21, 92.05 and 50.38, 95.51, 94.29, 56.67 respectively. A total of 134 patients were positive in reference standard InBios IgM ELISA. Conclusion This new rapid ST IgM kit validated for the first time in India, showed good sensitivity and specificity. As a Point-of-Care (PoC) test, the kit would be helpful in both urban and remote rural parts of India. PMID:28050364

filltex: Automatic queries to ADS and INSPIRE databases to fill LaTex bibliography

NASA Astrophysics Data System (ADS)

Gerosa, Davide; Vallisneri, Michele

2017-05-01

filltex is a simple tool to fill LaTex reference lists with records from the ADS and INSPIRE databases. ADS and INSPIRE are the most common databases used among the theoretical physics and astronomy scientific communities, respectively. filltex automatically looks for all citation labels present in a tex document and, by means of web-scraping, downloads all the required citation records from either of the two databases. filltex significantly speeds up the LaTex scientific writing workflow, as all required actions (compile the tex file, fill the bibliography, compile the bibliography, compile the tex file again) are automated in a single command. We also provide an integration of filltex for the macOS LaTex editor TexShop.

BioCapacitor: A novel principle for biosensors.

PubMed

Sode, Koji; Yamazaki, Tomohiko; Lee, Inyoung; Hanashi, Takuya; Tsugawa, Wakako

2016-02-15

Studies regarding biofuel cells utilizing biocatalysts such as enzymes and microorganisms as electrocatalysts have been vigorously conducted over the last two decades. Because of their environmental safety and sustainability, biofuel cells are expected to be used as clean power generators. Among several principles of biofuel cells, enzyme fuel cells have attracted significant attention for their use as alternative energy sources for future implantable devices, such as implantable insulin pumps and glucose sensors in artificial pancreas and pacemakers. However, the inherent issue of the biofuel cell principle is the low power of a single biofuel cell. The theoretical voltage of biofuel cells is limited by the redox potential of cofactors and/or mediators employed in the anode and cathode, which are inadequate for operating any devices used for biomedical application. These limitations inspired us to develop a novel biodevice based on an enzyme fuel cell that generates sufficient stable power to operate electric devices, designated "BioCapacitor." To increase voltage, the enzyme fuel cell is connected to a charge pump. To obtain a sufficient power and voltage to operate an electric device, a capacitor is used to store the potential generated by the charge pump. Using the combination of a charge pump and capacitor with an enzyme fuel cell, high voltages with sufficient temporary currents to operate an electric device were generated without changing the design and construction of the enzyme fuel cell. In this review, the BioCapacitor principle is described. The three different representative categories of biodevices employing the BioCapacitor principle are introduced. Further, the recent challenges in the developments of self-powered stand-alone biodevices employing enzyme fuel cells combined with charge pumps and capacitors are introduced. Finally, the future prospects of biodevices employing the BioCapacitor principle are addressed. Copyright © 2015 The Authors

Understanding the importance of transient resonances in extreme mass ratio inspirals

NASA Astrophysics Data System (ADS)

Berry, C. P. L.; Cole, R. H.; Cañizares, P.; Gair, J. R.

2017-05-01

Extreme mass ratio inspirals (EMRIs) occur when a compact object orbits a much larger one, like a solar-mass black hole around a supermassive black hole. The orbit has 3 frequencies which evolve through the inspiral. If the orbital radial frequency and polar frequency become commensurate, the system passes through a transient resonance. Evolving through resonance causes a jump in the evolution of the orbital parameters. We study these jumps and their impact on EMRI gravitational-wave detection. Jumps are smaller for lower eccentricity orbits; since most EMRIs have small eccentricities when passing through resonances, we expect that the impact on detection will be small. Neglecting the effects of transient resonances leads to a loss of ∼ 4% of detectable signals for an astrophysically motivated population of EMRIs.

Detection of mitotic nuclei in breast histopathology images using localized ACM and Random Kitchen Sink based classifier.

PubMed

Beevi, K Sabeena; Nair, Madhu S; Bindu, G R

2016-08-01

The exact measure of mitotic nuclei is a crucial parameter in breast cancer grading and prognosis. This can be achieved by improving the mitotic detection accuracy by careful design of segmentation and classification techniques. In this paper, segmentation of nuclei from breast histopathology images are carried out by Localized Active Contour Model (LACM) utilizing bio-inspired optimization techniques in the detection stage, in order to handle diffused intensities present along object boundaries. Further, the application of a new optimal machine learning algorithm capable of classifying strong non-linear data such as Random Kitchen Sink (RKS), shows improved classification performance. The proposed method has been tested on Mitosis detection in breast cancer histological images (MITOS) dataset provided for MITOS-ATYPIA CONTEST 2014. The proposed framework achieved 95% recall, 98% precision and 96% F-score.

Bio-Inspired Micromechanical Directional Acoustic Sensor

NASA Astrophysics Data System (ADS)

Swan, William; Alves, Fabio; Karunasiri, Gamani

Conventional directional sound sensors employ an array of spatially separated microphones and the direction is determined using arrival times and amplitudes. In nature, insects such as the Ormia ochracea fly can determine the direction of sound using a hearing organ much smaller than the wavelength of sound it detects. The fly's eardrums are mechanically coupled, only separated by about 1 mm, and have remarkable directional sensitivity. A micromechanical sensor based on the fly's hearing system was designed and fabricated on a silicon on insulator (SOI) substrate using MEMS technology. The sensor consists of two 1 mm2 wings connected using a bridge and to the substrate using two torsional legs. The dimensions of the sensor and material stiffness determine the frequency response of the sensor. The vibration of the wings in response to incident sound at the bending resonance was measured using a laser vibrometer and found to be about 1 μm/Pa. The electronic response of the sensor to sound was measured using integrated comb finger capacitors and found to be about 25 V/Pa. The fabricated sensors showed good directional sensitivity. In this talk, the design, fabrication and characteristics of the directional sound sensor will be described. Supported by ONR and TDSI.

Eyelid contour detection and tracking for startle research related eye-blink measurements from high-speed video records.

PubMed

Bernard, Florian; Deuter, Christian Eric; Gemmar, Peter; Schachinger, Hartmut

2013-10-01

Using the positions of the eyelids is an effective and contact-free way for the measurement of startle induced eye-blinks, which plays an important role in human psychophysiological research. To the best of our knowledge, no methods for an efficient detection and tracking of the exact eyelid contours in image sequences captured at high-speed exist that are conveniently usable by psychophysiological researchers. In this publication a semi-automatic model-based eyelid contour detection and tracking algorithm for the analysis of high-speed video recordings from an eye tracker is presented. As a large number of images have been acquired prior to method development it was important that our technique is able to deal with images that are recorded without any special parametrisation of the eye tracker. The method entails pupil detection, specular reflection removal and makes use of dynamic model adaption. In a proof-of-concept study we could achieve a correct detection rate of 90.6%. With this approach, we provide a feasible method to accurately assess eye-blinks from high-speed video recordings. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Biomimetic bio-inspired biomorph sustainable? An attempt to classify and clarify biology-derived technical developments.

PubMed

Speck, Olga; Speck, David; Horn, Rafael; Gantner, Johannes; Sedlbauer, Klaus Peter

2017-01-24

Over the last few decades, the systematic approach of knowledge transfer from biological concept generators to technical applications has received increasing attention, particularly because marketable bio-derived developments are often described as sustainable. The objective of this paper is to rationalize and refine the discussion about bio-derived developments also with respect to sustainability by taking descriptive, normative and emotional aspects into consideration. In the framework of supervised learning, a dataset of 70 biology-derived and technology-derived developments characterised by 9 different attributes together with their respective values and assigned to one of 17 classes was created. On the basis of the dataset a decision tree was generated which can be used as a straightforward classification tool to identify biology-derived and technology-derived developments. The validation of the applied learning procedure achieved an average accuracy of 90.0%. Additional extraordinary qualities of technical applications are generally discussed by means of selected biology-derived and technology-derived examples with reference to normative (contribution to sustainability) and emotional aspects (aesthetics and symbolic character). In the context of a case study from the building sector, all aspects are critically discussed.

Examples of variable speed limit applications : speed management workshop

DOT National Transportation Integrated Search

2000-01-09

VSL systems are a type of Intelligent Transportation System (ITS) that utilizes traffic : speed and volume detection, weather information, and road surface condition technology to determine appropriate speeds at which drivers should be traveling, giv...

Escaping blood-fed malaria mosquitoes minimize tactile detection without compromising on take-off speed.

PubMed

Muijres, F T; Chang, S W; van Veen, W G; Spitzen, J; Biemans, B T; Koehl, M A R; Dudley, R

2017-10-15

To escape after taking a blood meal, a mosquito must exert forces sufficiently high to take off when carrying a load roughly equal to its body weight, while simultaneously avoiding detection by minimizing tactile signals exerted on the host's skin. We studied this trade-off between escape speed and stealth in the malaria mosquito Anopheles coluzzii using 3D motion analysis of high-speed stereoscopic videos of mosquito take-offs and aerodynamic modeling. We found that during the push-off phase, mosquitoes enhanced take-off speed using aerodynamic forces generated by the beating wings in addition to leg-based push-off forces, whereby wing forces contributed 61% of the total push-off force. Exchanging leg-derived push-off forces for wing-derived aerodynamic forces allows the animal to reduce peak force production on the host's skin. By slowly extending their long legs throughout the push-off, mosquitoes spread push-off forces over a longer time window than insects with short legs, thereby further reducing peak leg forces. Using this specialized take-off behavior, mosquitoes are capable of reaching take-off speeds comparable to those of similarly sized fruit flies, but with weight-normalized peak leg forces that were only 27% of those of the fruit flies. By limiting peak leg forces, mosquitoes possibly reduce the chance of being detected by the host. The resulting combination of high take-off speed and low tactile signals on the host might help increase the mosquito's success in escaping from blood-hosts, which consequently also increases the chance of transmitting vector-borne diseases, such as malaria, to future hosts. © 2017. Published by The Company of Biologists Ltd.

Development of an artificial sensor for hydrodynamic detection inspired by a seal's whisker array.

PubMed

Eberhardt, William C; Wakefield, Brendan F; Murphy, Christin T; Casey, Caroline; Shakhsheer, Yousef; Calhoun, Benton H; Reichmuth, Colleen

2016-08-31

Nature has shaped effective biological sensory systems to receive complex stimuli generated by organisms moving through water. Similar abilities have not yet been fully developed in artificial systems for underwater detection and monitoring, but such technology would enable valuable applications for military, commercial, and scientific use. We set out to design a fluid motion sensor array inspired by the searching performance of seals, which use their whiskers to find and follow underwater wakes. This sensor prototype, called the Wake Information Detection and Tracking System (WIDTS), features multiple whisker-like elements that respond to hydrodynamic disturbances encountered while moving through water. To develop and test this system, we trained a captive harbor seal (Phoca vitulina) to wear a blindfold while tracking a remote-controlled, propeller-driven submarine. After mastering the tracking task, the seal learned to carry the WIDTS adjacent to its own vibrissal array during active pursuit of the target. Data from the WIDTS sensors describe changes in the deflection angles of the whisker elements as they pass through the hydrodynamic trail left by the submarine. Video performance data show that these detections coincide temporally with WIDTS-wake intersections. Deployment of the sensors on an actively searching seal allowed for the direct comparison of our instrument to the ability of the biological sensory system in a proof-of-concept demonstration. The creation of the WIDTS provides a foundation for instrument development in the field of biomimetic fluid sensor technology.

A novel approach to simulate chest wall micro-motion for bio-radar life detection purpose

NASA Astrophysics Data System (ADS)

An, Qiang; Li, Zhao; Liang, Fulai; Chen, Fuming; Wang, Jianqi

2016-10-01

Volunteers are often recruited to serve as the detection targets during the research process of bio-radar life detection technology, in which the experiment results are highly susceptible to the physical status of different individuals (shape, posture, etc.). In order to objectively evaluate the radar system performance and life detection algorithms, a standard detection target is urgently needed. The paper first proposed a parameter quantitatively controllable system to simulate the chest wall micro-motion caused mainly by breathing and heart beating. Then, the paper continued to analyze the material and size selection of the scattering body mounted on the simulation system from the perspective of back scattering energy. The computational electromagnetic method was employed to determine the exact scattering body. Finally, on-site experiments were carried out to verify the reliability of the simulation platform utilizing an IR UWB bioradar. Experimental result shows that the proposed system can simulate a real human target from three aspects: respiration frequency, amplitude and body surface scattering energy. Thus, it can be utilized as a substitute for a human target in radar based non-contact life detection research in various scenarios.

Single nucleotide polymorphism detection using gold nanoprobes and bio-microfluidic platform with embedded microlenses.

PubMed

Bernacka-Wojcik, Iwona; Águas, Hugo; Carlos, Fabio Ferreira; Lopes, Paulo; Wojcik, Pawel Jerzy; Costa, Mafalda Nascimento; Veigas, Bruno; Igreja, Rui; Fortunato, Elvira; Baptista, Pedro Viana; Martins, Rodrigo

2015-06-01

The use of microfluidics platforms combined with the optimal optical properties of gold nanoparticles has found plenty of application in molecular biosensing. This paper describes a bio-microfluidic platform coupled to a non-cross-linking colorimetric gold nanoprobe assay to detect a single nucleotide polymorphism associated with increased risk of obesity fat-mass and obesity-associated (FTO) rs9939609 (Carlos et al., 2014). The system enabled significant discrimination between positive and negative assays using a target DNA concentration of 5 ng/µL below the limit of detection of the conventionally used microplate reader (i.e., 15 ng/µL) with 10 times lower solution volume (i.e., 3 µL). A set of optimization of our previously reported bio-microfluidic platform (Bernacka-Wojcik et al., 2013) resulted in a 160% improvement of colorimetric analysis results. Incorporation of planar microlenses increased 6 times signal-to-loss ratio reaching the output optical fiber improving by 34% the colorimetric analysis of gold nanoparticles, while the implementation of an optoelectronic acquisition system yielded increased accuracy and reduced noise. The microfluidic chip was also integrated with a miniature fiber spectrometer to analyze the assays' colorimetric changes and also the LEDs transmission spectra when illuminating through various solutions. Furthermore, by coupling an optical microscope to a digital camera with a long exposure time (30 s), we could visualise the different scatter intensities of gold nanoparticles within channels following salt addition. These intensities correlate well to the expected difference in aggregation between FTO positive (none to small aggregates) and negative samples (large aggregates). © 2015 Wiley Periodicals, Inc.

Amoeba-inspired nanoarchitectonic computing implemented using electrical Brownian ratchets.

PubMed

Aono, M; Kasai, S; Kim, S-J; Wakabayashi, M; Miwa, H; Naruse, M

2015-06-12

In this study, we extracted the essential spatiotemporal dynamics that allow an amoeboid organism to solve a computationally demanding problem and adapt to its environment, thereby proposing a nature-inspired nanoarchitectonic computing system, which we implemented using a network of nanowire devices called 'electrical Brownian ratchets (EBRs)'. By utilizing the fluctuations generated from thermal energy in nanowire devices, we used our system to solve the satisfiability problem, which is a highly complex combinatorial problem related to a wide variety of practical applications. We evaluated the dependency of the solution search speed on its exploration parameter, which characterizes the fluctuation intensity of EBRs, using a simulation model of our system called 'AmoebaSAT-Brownian'. We found that AmoebaSAT-Brownian enhanced the solution searching speed dramatically when we imposed some constraints on the fluctuations in its time series and it outperformed a well-known stochastic local search method. These results suggest a new computing paradigm, which may allow high-speed problem solving to be implemented by interacting nanoscale devices with low power consumption.

The electromagnetic bio-field: clinical experiments and interferences.

PubMed

Burnei, G; Hodorogea, D; Georgescu, I; Gavriliu, Ş; Drăghici, I; Dan, D; Vlad, C; Drăghici, L

2012-06-12

One of the most important factors is the technical and scientifically rapid development that is continually modifying the world we live in and polluting it with electromagnetic radiations. A functional and structural influence of magnetic and electromagnetic field on living organisms is presented in the literature by many performed experiments. The notion of bio-field represents the electromagnetic field generated by the bio-structures, not only in their normal physiological activities but also in their pathological states. There is a tight interdependency between the bio-field and the bio-structure, which respects the primary notion of an electromagnetic field given by the Maxwell-Faraday laws, in which, the electromagnetic phenomena are simplified to the field variations. These variations can be expressed in a coherent differential equation system that bounds the field vectors to different space points at different time moments. The living organisms cannot contain electrostatic and magneto-static fields due to the intense activity of the bio-structures. The biochemical reactions that have high rhythms and speeds always impose the electrodynamics character of the biologic field that also corresponds to the stability of the protein molecule that can be explained only through a dynamic way. The existent energy is not considered an exciting agent, and it does not lead to any effects. The parameters of these elementary bio-fields cannot yet be fully known due to technical reasons. The biological structures are very complex ones and undergo continuous dynamical activity. That is why the calculus model should be related to the constant dynamics, nowadays being very difficult to express.

High-speed detection of DNA translocation in nanopipettes

NASA Astrophysics Data System (ADS)

Fraccari, Raquel L.; Ciccarella, Pietro; Bahrami, Azadeh; Carminati, Marco; Ferrari, Giorgio; Albrecht, Tim

2016-03-01

We present a high-speed electrical detection scheme based on a custom-designed CMOS amplifier which allows the analysis of DNA translocation in glass nanopipettes on a microsecond timescale. Translocation of different DNA lengths in KCl electrolyte provides a scaling factor of the DNA translocation time equal to p = 1.22, which is different from values observed previously with nanopipettes in LiCl electrolyte or with nanopores. Based on a theoretical model involving electrophoresis, hydrodynamics and surface friction, we show that the experimentally observed range of p-values may be the result of, or at least be affected by DNA adsorption and friction between the DNA and the substrate surface.We present a high-speed electrical detection scheme based on a custom-designed CMOS amplifier which allows the analysis of DNA translocation in glass nanopipettes on a microsecond timescale. Translocation of different DNA lengths in KCl electrolyte provides a scaling factor of the DNA translocation time equal to p = 1.22, which is different from values observed previously with nanopipettes in LiCl electrolyte or with nanopores. Based on a theoretical model involving electrophoresis, hydrodynamics and surface friction, we show that the experimentally observed range of p-values may be the result of, or at least be affected by DNA adsorption and friction between the DNA and the substrate surface. Electronic supplementary information (ESI) available: Gel electrophoresis confirming lengths and purity of DNA samples, comparison between Axopatch 200B and custom-built setup, comprehensive low-noise amplifier characterization, representative I-V curves of nanopipettes used, typical scatter plots of τ vs. peak amplitude for the four LDNA's used, table of most probable τ values, a comparison between different fitting models for the DNA translocation time distribution, further details on the stochastic numerical simulation of the scaling statistics and the derivation of the extended

Bacteriophages and phage-inspired nanocarriers for targeted delivery of therapeutic cargos.

PubMed

Karimi, Mahdi; Mirshekari, Hamed; Moosavi Basri, Seyed Masoud; Bahrami, Sajad; Moghoofei, Mohsen; Hamblin, Michael R

2016-11-15

The main goal of drug delivery systems is to target therapeutic cargoes to desired cells and to ensure their efficient uptake. Recently a number of studies have focused on designing bio-inspired nanocarriers, such as bacteriophages, and synthetic carriers based on the bacteriophage structure. Bacteriophages are viruses that specifically recognize their bacterial hosts. They can replicate only inside their host cell and can act as natural gene carriers. Each type of phage has a particular shape, a different capacity for loading cargo, a specific production time, and their own mechanisms of supramolecular assembly, that have enabled them to act as tunable carriers. New phage-based technologies have led to the construction of different peptide libraries, and recognition abilities provided by novel targeting ligands. Phage hybridization with non-organic compounds introduces new properties to phages and could be a suitable strategy for construction of bio-inorganic carriers. In this review we try to cover the major phage species that have been used in drug and gene delivery systems, and the biological application of phages as novel targeting ligands and targeted therapeutics. Copyright © 2016 Elsevier B.V. All rights reserved.

Diffraction-based BioCD biosensor for point-of-care diagnostics

NASA Astrophysics Data System (ADS)

Choi, H.; Chang, C.; Savran, C.; Nolte, D.

2018-02-01

The BioCD platform technology uses spinning-disk interferometry to detect molecular binding to target molecular probes in biological samples. Interferometric configurations have included differential phase contrast and in-line quadrature detection. For the detection of extremely low analyte concentrations, nano- or microparticles can enhance the signal through background-free diffraction detection. Diffraction signal measurements on BioCD biosensors are achieved by forming gratings on a disc surface. The grating pattern was printed with biotinylated bovine serum albumin (BSA) and streptavidin coated beads were deployed. The diameter of the beads was 1 micron and strong protein bonding occurs between BSA and streptavidin-coated beads at the printed location. The wavelength for the protein binding detection was 635 nm. The periodic pattern on the disc amplified scattered light into the first-order diffraction position. The diffracted signal contains Mie scattering and a randomly-distributed-bead noise contributions. Variation of the grating pattern periodicity modulates the diffraction efficiency. To test multiple spatial frequencies within a single scan, we designed a fan-shaped grating to perform frequency filter multiplexing on a diffraction-based BioCD.

A Powerful Molecular Engineering Tool Provided Efficient Chlamydomonas Mutants as Bio-Sensing Elements for Herbicides Detection

PubMed Central

Lambreva, Maya D.; Giardi, Maria Teresa; Rambaldi, Irene; Antonacci, Amina; Pastorelli, Sandro; Bertalan, Ivo; Husu, Ivan; Johanningmeier, Udo; Rea, Giuseppina

2013-01-01

This study was prompted by increasing concerns about ecological damage and human health threats derived by persistent contamination of water and soil with herbicides, and emerging of bio-sensing technology as powerful, fast and efficient tool for the identification of such hazards. This work is aimed at overcoming principal limitations negatively affecting the whole-cell-based biosensors performance due to inadequate stability and sensitivity of the bio-recognition element. The novel bio-sensing elements for the detection of herbicides were generated exploiting the power of molecular engineering in order to improve the performance of photosynthetic complexes. The new phenotypes were produced by an in vitro directed evolution strategy targeted at the photosystem II (PSII) D1 protein of Chlamydomonas reinhardtii, using exposures to radical-generating ionizing radiation as selection pressure. These tools proved successful to identify D1 mutations conferring enhanced stability, tolerance to free-radical-associated stress and competence for herbicide perception. Long-term stability tests of PSII performance revealed the mutants capability to deal with oxidative stress-related conditions. Furthermore, dose-response experiments indicated the strains having increased sensitivity or resistance to triazine and urea type herbicides with I50 values ranging from 6×10−8 M to 2×10−6 M. Besides stressing the relevance of several amino acids for PSII photochemistry and herbicide sensing, the possibility to improve the specificity of whole-cell-based biosensors, via coupling herbicide-sensitive with herbicide-resistant strains, was verified. PMID:23613953

A dual amplification strategy for DNA detection combining bio-barcode assay and metal-enhanced fluorescence modality.

PubMed

Zhou, Zhenpeng; Li, Tian; Huang, Hongduan; Chen, Yang; Liu, Feng; Huang, Chengzhi; Li, Na

2014-11-11

Silver-enhanced fluorescence was coupled with a bio-barcode assay to facilitate a dual amplification assay to demonstrate a non-enzymatic approach for simple and sensitive detection of DNA. In the assay design, magnetic nanoparticles seeded with silver nanoparticles were modified with the capture DNA, and silver nanoparticles were modified with the binding of ssDNA and the fluorescently labeled barcode dsDNA. Upon introduction of the target DNA, a sandwich structure was formed because of the hybridization reaction. By simple magnetic separation, silver-enhanced fluorescence of barcode DNAs could be readily measured without the need of a further step to liberate barcode DNAs from silver nanoparticles, endowing the method with simplicity and high sensitivity with a detection limit of 1 pM.

Bacteriophage-Based Pathogen Detection

NASA Astrophysics Data System (ADS)

Ripp, Steven

Considered the most abundant organism on Earth, at a population approaching 1031, bacteriophage, or phage for short, mediate interactions with myriad bacterial hosts that has for decades been exploited in phage typing schemes for signature identification of clinical, food-borne, and water-borne pathogens. With over 5,000 phage being morphologically characterized and grouped as to susceptible host, there exists an enormous cache of bacterial-specific sensors that has more recently been incorporated into novel bio-recognition assays with heightened sensitivity, specificity, and speed. These assays take many forms, ranging from straightforward visualization of labeled phage as they attach to their specific bacterial hosts to reporter phage that genetically deposit trackable signals within their bacterial hosts to the detection of progeny phage or other uniquely identifiable elements released from infected host cells. A comprehensive review of these and other phage-based detection assays, as directed towards the detection and monitoring of bacterial pathogens, will be provided in this chapter.

Smart Nacre-inspired Nanocomposites.

PubMed

Peng, Jingsong; Cheng, Qunfeng

2018-03-15

Nacre-inspired nanocomposites with excellent mechanical properties have achieved remarkable attention in the past decades. The high performance of nacre-inspired nanocomposites is a good basis for the further application of smart devices. Recently, some smart nanocomposites inspired by nacre have demonstrated good mechanical properties as well as effective and stable stimuli-responsive functions. In this Concept, we summarize the recent development of smart nacre-inspired nanocomposites, including 1D fibers, 2D films and 3D bulk nanocomposites, in response to temperature, moisture, light, strain, and so on. We show that diverse smart nanocomposites could be designed by combining various conventional fabrication methods of nacre-inspired nanocomposites with responsive building blocks and interface interactions. The nacre-inspired strategy is versatile for different kinds of smart nanocomposites in extensive applications, such as strain sensors, displays, artificial muscles, robotics, and so on, and may act as an effective roadmap for designing smart nanocomposites in the future. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

A locust-inspired miniature jumping robot.

PubMed

Zaitsev, Valentin; Gvirsman, Omer; Ben Hanan, Uri; Weiss, Avi; Ayali, Amir; Kosa, Gabor

2015-11-25

Unmanned ground vehicles are mostly wheeled, tracked, or legged. These locomotion mechanisms have a limited ability to traverse rough terrain and obstacles that are higher than the robot's center of mass. In order to improve the mobility of small robots it is necessary to expand the variety of their motion gaits. Jumping is one of nature's solutions to the challenge of mobility in difficult terrain. The desert locust is the model for the presented bio-inspired design of a jumping mechanism for a small mobile robot. The basic mechanism is similar to that of the semilunar process in the hind legs of the locust, and is based on the cocking of a torsional spring by wrapping a tendon-like wire around the shaft of a miniature motor. In this study we present the jumping mechanism design, and the manufacturing and performance analysis of two demonstrator prototypes. The most advanced jumping robot demonstrator is power autonomous, weighs 23 gr, and is capable of jumping to a height of 3.35 m, covering a distance of 1.37 m.

An aptamer-based bio-barcode assay with isothermal recombinase polymerase amplification for cytochrome-c detection and anti-cancer drug screening.

PubMed

Loo, Jacky F C; Lau, P M; Ho, H P; Kong, S K

2013-10-15

Based on a recently reported ultra-sensitive bio-barcode (BBC) assay, we have developed an aptamer-based bio-barcode (ABC) alternative to detect a cell death marker cytochrome-c (Cyto-c) and its subsequent application to screen anti-cancer drugs. Aptamer is a short single-stranded DNA selected from a synthetic DNA library by virtue of its high binding affinity and specificity to its target based on its unique 3D structure from the nucleotide sequence after folding. In the BBC assay, an antigen (Ag) in analytes is captured by a micro-magnetic particle (MMP) coated with capturing antibodies (Abs). Gold nanoparticles (NPs) with another recognition Ab against the same target and hundreds of identical DNA molecules of known sequence are subsequently added to allow the formation of sandwich structures ([MMP-Ab1]-Ag-[Ab2-NP-DNA]). After isolating the sandwiches by a magnetic field, the DNAs hybridized to their complementary DNAs covalently bound on the NPs are released from the sandwiches after heating. Acting as an Ag identification tag, these bio-barcode DNAs with known DNA sequence are then amplified by polymerase chain reaction (PCR) and detected by fluorescence. In our ABC assay, we employed a Cyto-c-specific aptamer to substitute both the recognition Ab and barcode DNAs on the NPs in the BBC assay; and a novel isothermal recombinase polymerase amplification for the time-consuming PCR. The detection limit of our ABC assay for the Cyto-c was found to be 10 ng/mL and this new assay can be completed within 3h. Several potential anti-cancer drugs have been tested in vitro for their efficacy to kill liver cancer with or without multi-drug resistance. © 2013 Elsevier B.V. All rights reserved.

Kirigami artificial muscles with complex biologically inspired morphologies

NASA Astrophysics Data System (ADS)

Sareh, Sina; Rossiter, Jonathan

2013-01-01

In this paper we present bio-inspired smart structures which exploit the actuation of flexible ionic polymer composites and the kirigami design principle. Kirigami design is used to convert planar actuators into active 3D structures capable of large out-of-plane displacement and that replicate biological mechanisms. Here we present the burstbot, a fluid control and propulsion mechanism based on the atrioventricular cuspid valve, and the vortibot, a spiral actuator based on Vorticella campanula, a ciliate protozoa. Models derived from biological counterparts are used as a platform for design optimization and actuator performance measurement. The symmetric and asymmetric fluid interactions of the burstbot are investigated and the effectiveness in fluid transport applications is demonstrated. The vortibot actuator is geometrically optimized as a camera positioner capable of 360° scanning. Experimental results for a one-turn spiral actuator show complex actuation derived from a single degree of freedom control signal.

Limb locomotion--speed distribution analysis as a new method for stance phase detection.

PubMed

Peham, C; Scheidl, M; Licka, T

1999-10-01

The stance phase is used for the determination of many parameters in motion analysis. In this technical note the authors present a new kinematical method for determination of stance phase. From the high-speed video data, the speed distribution of the horizontal motion of the distal limb is calculated. The speed with the maximum occurrence within the motion cycle defines the stance phase, and this speed is used as threshold for beginning and end of the stance phase. In seven horses the results obtained with the presented method were compared to synchronous stance phase determination using a force plate integrated in a hard track. The mean difference between the results was 10.8 ms, equalling 1.44% of mean stance phase duration. As a test, the presented method was applied to a horse trotting on the treadmill, and to a human walking on concrete. This article describes an easy and safe method for stance phase determination in continuous kinematic data and proves the reliability of the method by comparing it to kinetic stance phase detection. This method may be applied in several species and all gaits, on the treadmill and on firm ground.

Bio-Inspired Sensing and Display of Polarization Imagery

DTIC Science & Technology

2005-07-17

and weighting coefficients in this example. Panel 4D clearly shows a better visibility, feature extraction , and lesser effect from the background...of linear polarization. Panel E represents the segmentation of the degree of linear polarization, and then Panel F shows the extracted segment with...polarization, and Panel F shows the segment extraction with the finger print selected. Panel G illustrates the application of Canny edge detection to

Towards enhancement of performance of K-means clustering using nature-inspired optimization algorithms.

PubMed

Fong, Simon; Deb, Suash; Yang, Xin-She; Zhuang, Yan

2014-01-01

Traditional K-means clustering algorithms have the drawback of getting stuck at local optima that depend on the random values of initial centroids. Optimization algorithms have their advantages in guiding iterative computation to search for global optima while avoiding local optima. The algorithms help speed up the clustering process by converging into a global optimum early with multiple search agents in action. Inspired by nature, some contemporary optimization algorithms which include Ant, Bat, Cuckoo, Firefly, and Wolf search algorithms mimic the swarming behavior allowing them to cooperatively steer towards an optimal objective within a reasonable time. It is known that these so-called nature-inspired optimization algorithms have their own characteristics as well as pros and cons in different applications. When these algorithms are combined with K-means clustering mechanism for the sake of enhancing its clustering quality by avoiding local optima and finding global optima, the new hybrids are anticipated to produce unprecedented performance. In this paper, we report the results of our evaluation experiments on the integration of nature-inspired optimization methods into K-means algorithms. In addition to the standard evaluation metrics in evaluating clustering quality, the extended K-means algorithms that are empowered by nature-inspired optimization methods are applied on image segmentation as a case study of application scenario.

A nano grating tunable MEMS optical filter for high-speed on-chip multispectral fluorescent detection.

PubMed

Truxal, Steven C; Huang, Nien-Tsu; Kurabayashi, Katsuo

2009-01-01

We report a microelectromechanical (MEMS) tunable optical filter and its integration in a fluorescence microscope for high speed on-chip spectral measurements. This integration allows for measurements of any fluorescence sample placed onto the microscope stage. We demonstrate the system capabilities by taking spectral measurements of multicolor fluorescent beads and fluorescently labeled cells passing through a microfluidic cytometer. The system has applications in biological studies where the measurement of multiple fluorescent peaks is restricted by the detection method's speed and sensitivity.