bluuebunny/crossref_metadata_2025 huggingface dataset:
Status and impacts of non‐native freshwater fish on fisheries biodiversity and biogeography in Kenya: A management perspective
Authors: Okwiri Brian , Donde Oscar Omondi , Kibet Caroline Jepkorir
Published: December 2019

The introduction and spread of non‐native fish species in Kenyan inland freshwater systems are affecting the integrity of Kenya's aquatic biodiversity and ecosystems. The present study investigated the existing knowledge of non‐native fishes in Kenyan inland freshwater systems and their consequential implications regarding fisheries management. A total of 29 non‐native fish species have been introduced to Kenyan inland freshwater systems, with 20 of these being alien fish species and nine extralimital. These introductions have increased the fish faunal compositional similarity of inland drainage systems by 4.1% to a current similarity of 26.9%, compared to a historical similarity of 22.8%. Documented impacts of this situation include displacements, predation, competition, hybridization, habitat modification and disease transmission, all of which have had negative impacts on the status and management of Kenyan freshwater fisheries. The present study addresses the taxonomic bias created by existing studies on non‐native fishes focusing on individual species, by providing more information on the status of other non‐native species about which information is limited and whose status is uncertain. The present study presents information that can be used in management efforts to control invasions and mitigate their negative impacts.
“Neuromyths”: A Critical Consideration
Authors: Gardner Howard
Published: December 2019

The term “neuromyth” is becoming part of discourse in the field of mind, brain, and education. In this article, I review some problematic aspects of the practice, critique specific examples, and propose an alternative way of communicating with the public about findings in psychology and neuroscience.
Neuropathology in Pitié‐Salpêtrière hospital: Past, present and prospect
Authors: Seilhean Danielle
Published: December 2019

Pitié and La Salpêtrière, both founded in the17th century, were for long two distinct hospitals until they merged in 1964. The name La Salpêtrière is inherited from the initial purpose of the buildings designed to produce saltpeter for gun powder. But the place was soon transformed into an asylum to shelter the poor and the insane. From the care of this underprivileged population, alienists such as Pinel have paved the way for modern medicine for the mentally ill at the time of the French Revolution. In the second half of the 19th century, Jean‐Martin Charcot and his students laid the foundations of modern neurology from the observation of the large population hosted in La Salpêtrière, mostly women with severe chronic diseases. Charcot led clinicopathological studies in almost all the fields of nervous system disorders. His successors (including Raymond, Dejerine, Pierre Marie) maintained the same close relationship between clinical neurology and neuropathology. In parallel with the development of neurosurgery at Pitié hospital, neuropathology first spread through small laboratories attached to clinical departments. The merger of the two hospitals in the early '60s coincided with the creation of a large university hospital in which the care and study of diseases of the nervous system were preponderant. An independent laboratory of neuropathology was created, led by Raymond Escourolle. This period was on the eve of important developments in neuroscience around the world. Today, the Pitié‐Salpêtrière neuropathology laboratory still plays a central role between neurology and neurosurgery clinics and major research institutes such as the Brain Institute, callled Institut du Cerveau et de la Moelle (ICM), and the Institute of Myology.
The Delhi Bias: knowledge hegemony of India's slum governance
Authors: Palat Narayanan Nipesh
Published: December 2019

Slum eradication has been a concern in South Asian cities since the colonial times. Legislation and policies are being framed both out of national desires and international strategies. However, very little is being studied on how these legislation and policies come into being, specifically geography's influence in their formulation. The article analyses parliamentary debates from India (Rajya Sabha, 1953–2014), and outlines the process of historical, political, and institutional dominance of Delhi. It shows that the slum legislation and policies in India are formulated by abstracting cases from the Delhi slums. This knowledge hegemony of Delhi is discussed within the growing consideration towards urban theory's southern shift, which puts the Southern cities (megacities) as underdogs. The paper argues that at a regional level, these megacities exert the same hegemony that the southern theory wants to avoid. The results argue towards broadening the southern theory and ordinary city discussions.
Culture, parenting, and language: Respeto in Latine mother–child interactions
Authors: Tamis‐LeMonda Catherine S. , Caughy Margaret O'Brien , Rojas Raúl , Bakeman Roger , Adamson Lauren B. , Pacheco Daniel , Owen Margaret Tresch , Suma Katharine , Pace Amy
Published: December 2019

The cultural value ofrespeto(respect) is central to Latine parenting. Yet, how respeto manifests in the interactions of Latine parents and their young children remains unexamined. Low‐income Mexican immigrant Spanish‐speaking mothers and their 2.5‐year‐old toddlers (N = 128) were video‐recorded during play (Mage = 30.2 months,SD = 0.52), and two culturally informed items of respeto were coded: parent calm authority and child affiliative obedience. Respeto related to standard ratings of mother and child interactions (e.g., maternal sensitivity and child engagement) but also captured unique features of parent–child interactions. Respeto related to mothers' and toddlers' language production and discourse during the interaction, and explained unique variance in language variables above standard ratings of mother–child interaction. This is the first effort to document a culturally salient aspect of dyadic interaction in Mexican immigrant mothers and young children and to show that respeto relates to language use during mother–child interactions.
The morphological evolution of the Adephaga (Coleoptera)
Authors: Beutel Rolf Georg , Ribera Ignacio , Fikáček Martin , Vasilikopoulos Alexandros , Misof Bernhard , Balke Michael
Published: December 2019

The evolution of the coleopteran suborder Adephaga is discussed based on a robust phylogenetic background. Analyses of morphological characters yield results nearly identical to recent molecular phylogenies, with the highly specialized Gyrinidae placed as sister to the remaining families, which form two large, reciprocally monophyletic subunits, the aquatic Haliplidae + Dytiscoidea (Meruidae, Noteridae, Aspidytidae, Amphizoidae, Hygrobiidae, Dytiscidae) on one hand, and the terrestrial Geadephaga (Trachypachidae + Carabidae) on the other. The ancestral habitat of Adephaga, either terrestrial or aquatic, remains ambiguous. The former option would imply two or three independent invasions of aquatic habitats, with very different structural adaptations in larvae of Gyrinidae, Haliplidae and Dytiscoidea.
l‐Citrulline supplementation improves glucose and exercise tolerance in obese male mice
Authors: Eshreif Amina , Al Batran Rami , Jamieson K. Lockhart , Darwesh Ahmed M. , Gopal Keshav , Greenwell Amanda A. , Zlobine Igor , Aburasayn Hanin , Eaton Farah , Mulvihill Erin E. , Campbell Jonathan E. , Seubert John M. , Ussher John R.
Published: December 2019

New Findings

What is the central question of the study?

Does the action of l‐citrulline, which has been shown to augment performance in animals and athletes, possibly via increasing mitochondrial function, translate to obese animals, and does this improve glycaemia?

What is the main finding and its importance?

Chronic supplementation with l‐citrulline improves not only exercise capacity, but also glycaemia in obese mice, which would be beneficial as obese individuals are at increased risk for type 2 diabetes. However, l‐citrulline supplementation also caused a mild impairment in insulin signalling and insulin tolerance in obese mice.

l‐Citrulline is an organic α‐amino acid that has been shown to have a number of salutary actions on whole‐body physiology, including reducing muscle wasting and augmenting exercise and muscle performance. The latter has been suggested to arise from elevations in mitochondrial function. Because enhancing mitochondrial function has been proposed as a novel strategy to mitigate insulin resistance, our goal was to determine whether supplementation with l‐citrulline could also improve glycaemia in an experimental mouse model of obesity. We hypothesized that l‐citrulline treatment would improve glycaemia in obese mice, and this would be associated with elevations in skeletal muscle mitochondrial function. Ten‐week‐old C57BL/6J mice were fed either a low‐fat (10% kcal from lard) or a high‐fat (60% kcal from lard) diet, while receiving drinking water supplemented with either vehicle or l‐citrulline (0.6 g l−1) for 15 weeks. Glucose homeostasis was assessed via glucose/insulin tolerance testing, while in vivo metabolism was assessed via indirect calorimetry, and forced exercise treadmill testing was utilized to assess endurance. As expected, obese mice supplemented with l‐citrulline exhibited an increase in exercise capacity, which was associated with an improvement in glucose tolerance. Consistent with augmented mitochondrial function, we observed an increase in whole body oxygen consumption rates in obese mice supplemented with l‐citrulline. Surprisingly, l‐citrulline supplementation worsened insulin tolerance and reduced insulin signalling in obese mice. Taken together, although l‐citrulline supplementation improves both glucose tolerance and exercise capacity in obese mice, caution must be applied with its broad use as a nutraceutical due to a potential deterioration of insulin sensitivity.
Transduction Using Functional Materials: Basic Science and Understanding at the U. S. Naval Research Laboratory
Authors: DeGiorgi Virginia G. , Finkel Peter , Garten Lauren , Staruch Margo
Published: December 2019

Recently NRL researchers have embarked on a basic research effort “Tuning Giant Magnetoelectric Properties in Phase Transformation Multiferroics” focused on multifunctional materials for energy transduction and conversion. Multiferroic materials combine at least two coupled ferroic properties and are used in multiple applications including magnetic field sensors, energy harvesting devices, non-volatile memory and antennas. There are very few single phase multiferroic materials, and they normally have relatively low magnetoelectric (ME) coupling coefficient. In contrast, engineered materials such as ME composites fabricated from piezoelectric and magnetostrictive materials can show multiple orders of magnitudes increase in the ME coupling coefficient. The optimal design of ME composites would lead to conditions of maximum response (strain, induced voltage, or field) with minimum applied electric or magnetic fields, providing advanced materials for transduction, sensing, energy harvesting and other applications. That is why NRL researchers are working on piezoelectric materials with enhanced properties due to a phase transformation that would minimize the stimuli needed to achieve large strains. Key to the successful design and fabrication of ME composites is an understanding of interface characteristics as well as individual material components. In this paper we will review the current status of work at NRL on engineered multiferroic composites comprised of piezoelectric and magnetostrictive materials coupled through strain. There are still many open questions about the interfacial properties as well as the individual component materials. Details will be presented from recent work on material characterization under repetitive cycling, interface characteristics, and stress/electric/thermal effects on driving the phase transition in a relaxor ferroelectric single crystal.
A High-Fidelity Dynamic Model for Origami Based on Iso-Parametric Absolute Nodal Coordinate Formulation (Iso-ANCF)
Authors: Tao Jiayue , Li Suyi
Published: December 2019

Origami-inspired structures and material systems have been used in many engineering applications because of their unique kinematic and mechanical properties induced by folding. However, accurately modeling and analyzing origami folding and the associated mechanical properties are challenging, especially when large deformation and dynamic responses need to be considered. In this paper, we formulate a high-fidelity model — based on the iso-parametric Absolute Nodal Coordinate Formulation (ANCF) — for simulating the dynamic folding behaviors of origami involving large deformation. The center piece of this new model is the characterization of crease deformation. To this end, we model the crease using rotational spring at the nodes. The corresponding folding angle is calculated based on the local surface normal vectors. Compared to the currently popular analytical methods for analyzing origami, such as the rigid-facet and equivalent bar-hinge approach, this new model is more accurate in that it can describe the large crease and facet deformation without imposing many assumptions. Meanwhile, the ANCF based origami model can be more efficient computationally compared to the traditional finite element simulations. Therefore, this new model can lay down the foundation for high-fidelity origami analysis and design that involve mechanics and dynamics.
An Electrical Impedance Tomography Drive Pattern for Fast and Accurate Gesture Recognition With Less Electrodes
Authors: Ma Gang , Hao Zhiliang , Wu Xuan , Wang Xiaojie
Published: December 2019

This paper presents an optimal Electrical Impedance Tomography (EIT) drive pattern for real-time gesture recognition, which can reduce the measurement time and realize a performance trade-off between the accuracy and the time response. This method is achieved by feature selection and model explanation. We designed eleven hand gestures to verify the proposed approach. Compared to the 8-electrode method, the optimal electrode drive pattern achieved a recognition accuracy of 97.5% with seven electrodes and the measurement time was reduced by 60%. To illustrate the universality of this method, we performed a contact detection experiment. By setting seven labels on the conductive panel and using optimal electrode drive pattern, the detection accuracy reached 100% with seven electrodes and the measurement time was reduced by 85%.
Design and Testing of a Wall-Climbing Robot With Under-Actuated Force Adjusting Mechanism
Authors: Wu Xuan , Liu Hong , Wang Xiaojie
Published: December 2019

The paper introduces the design and testing of a tank-like modular wall-climbing robot (WCR). Firstly, a bioinspired dry adhesive patterned with papilla-like array is fabricated, and its quasi-static adhesive properties is tested and evaluated. Based on the material’s properties, a single tank-like module using timing adhesive belts is optimally designed for maximum adhesive force. An under-actuated four-bar compliant linkage is utilized to connect the two modules of the WCR. The lengths of the linkage are optimized in keeping both of the modules having constant preloading forces on surfaces with different inclinations. Experimental results show that the compliant link functions like the digital joint of the gecko that is able to maintain enough preloading force for each module on the surfaces of variable inclinations, making the robot adapted to surface transitioning easily.
Transient Fluid-Structure Interaction Analysis of a Solid State Ornithopter Wing
Authors: Katibeh Mohammad , Bilgen Onur
Published: December 2019

One of the means of flight is via flapping and there were many attempts to mimic the wing motion of a bird for centuries. One interesting concept for achieving flight via flapping is the so-called solid-state ornithopter concept which works by using induced strain actuators such as piezoelectric materials for flapping. In this research, we seek to gain a better understanding of the feasibility and performance of the solid-state ornithopter concept. In this paper, the purpose is to analyze a solid state ornithopter wing concept and to study the effect of different geometric parameters. A two-way fluid-structure interaction analysis method is utilized since the geometry of the wing is changing throughout the flapping cycle, and the fluid and the solid domains interact significantly. A parameterized model is utilized in both solid and fluid domains, and the two domains are coupled. Different geometric parameters are defined in the model so that the system-level performance metrics as a function of each parameter can be examined.
A Bioinspired Piezocomposite Peristaltic Pump: An Electromechanical Euler-Bernoulli Beam Model and Parametric Analysis
Authors: Shan Xin , Bilgen Onur
Published: December 2019

This paper investigates the optimal geometric parameters for a bioinspired peristaltic piezocomposite pump with the use of an electromechanical Euler-Bernoulli beam model. The peristaltic pump is a self-contained propulsion system involving a series of piezo-active soft cymbal-like segments that are connected with passive soft connective segments. A series of phased excitations in expansion and contraction applied to different active segments of the channel create a traveling wave along the axis of the channel, which in return “propels” the fluid in one direction. A parametric analysis, based on the Euler-Bernoulli beam model, is conducted to improve the effectiveness of the cymbal-like piezocomposite actuators. Area change of the cymbal-like actuators, which is correlated to the propulsion power, is studied based on the analysis of the moment, curvature, and area change due to excitation. Area change is also used to evaluate the effectiveness, and to decide the optimal geometric parameters of the piezocomposite actuators.
Self-Sensing for Twisted String Actuators Using Conductive Supercoiled Polymers
Authors: Bombara David , Mansurov Vasilii , Konda Revanth , Fowzer Steven , Zhang Jun
Published: December 2019

The twisted string actuator (TSA), as a recently discovered artificial muscle, has attracted a lot of attention as a compliant and powerful actuation mechanism. A TSA consists of two strings attached to a motor on one end and a load on the other end. The motor’s rotation twists the strings and generates linear actuation. A common challenge is to obtain TSAs’ strains using compact approaches. Previous studies exclusively utilized external position sensors that not only increased system cost, size and complexity, but also lowered actuator compliance. In this paper, self-sensing strategies are presented to estimate TSAs’ strains without external sensors. By incorporating conductive and stretchable nylon strings, called super-coiled polymer (SCP) strings, into TSAs, their strains can be estimated from the resistance values of SCP strings. Two self-sensing configurations are realized: (1) TSA with one regular string and one SCP string, and (2) TSA with two SCP strings. Experiments are conducted to show the correlation between the length and resistance of TSA under different conditions. Polynomial and Preisach hysteresis models were successfully employed to capture the Length – Resistance correlation and to estimate TSA’s length using the resistance.
Evaluating Fretting Wear on 3D-Printed α-, β-, γ- Additives Hybridized NiTi Shape Memory Alloy
Authors: Bodunde O. P. , Gao S. M. , Qin M. , Liao W. H.
Published: December 2019

Nickel-Titanium (NiTi) shape memory alloys (SMAs) are a class of promising materials for bio-implant, transportation, and aerospace applications. These interesting applications of SMA are as a result of their ability to exhibit shape memory effect (SME) and super-elasticity (SE). SMAs, especially NiTi which has been proven to have good mechanical properties, are however limited by their operational fatigue as reported in the literature. In this paper, a near equiatomic NiTi SMA was hybridized with zirconium (Zr), molybdenum (Mo) and copper (Cu), which are available and economic viable α-, β-, γ- stabilizing additives suitable for NiTi SMAs. Each of Zr, Mo, Cu were hybridized separately with the bare near equiatomic NiTi SMA. The compositional requirements for each of the sub-hybrids (NiTi-α, NiTi-β, and NiTi-γ respectively) were experimentally determined to know the optimum composition which could indicate the presence of austenitic and martensitic phases. Scan electron microscopy (SEM) was performed on each of the hybridizing additives as well as the bare equiatomic NiTi to determine their particle sizes and investigate their compatibility (between 30 and 40 microns) with the 3D printer used in the study. X-ray diffractometric (XRD) analysis also was carried out on the bare SMA and its additives to determine the presence of B2 and B19’ peaks. Afterward, NiTi-α, NiTi-β, and NiTi-γ were 3D printed to produce fretting wear test specimens and finally, the fretting wear behaviors of the NiTi hybrids were studied in detail with the objective of testing their performances under fretting wear mode as it may be required for an application. A tungsten carbide counter-body was used. The results from the characterization through XRD indicated that all of α-, β-, γ- stabilizing additives with NiTi respectively showed the presence of B2 and B19’ in the inter-metallic phases. Details of wear microstructure were reported and its information could be useful for professionals who require hybridized NiTi alloys for various engineering applications.
Energy Harvesting From the Vibration and Rotation of Host Systems Using Piezoelectric Devices
Authors: Cooley Christopher G.
Published: December 2019

This work analyzes the energy harvested by a piezoelectric vibration energy harvester that is attached to a rotating host system, like an automotive tire, that has superposed translational vibration. The device experiences once-per-revolution dynamic excitation from rotation and, because the host system translates, additional speed-dependent excitation from input vibration. The device consists of a piezoelectric beam with a proof mass that displaces tangentially in operation so that large, troublesome centripetal accelerations can be avoided. The dynamic response and power harvested are determined in closed-form. The speed-dependent properties of the response components are determined. With excitation from rotation and vibration, the device harvests substantially more power than if the system were excited by either rotation or vibration alone. Numerical results are shown for an example device over a wide range of rotation speeds. The device can harvest 185 mW of power at its maximum when the rotation speed is near 1,000 rpm. The device provides more than 30 mW of power for speeds between 817 rpm and 1,195 rpm. Harvesting energy from vibration naturally leads to wider speed bandwidths where large amounts of power are available.
Pneumatic Artificial Muscle Development and Manufacturing Process and Verification Testing for Space Flight Application
Authors: Netwall Christopher J. , Thomas James P. , Kubista Michael S. , Griffith Kerry A. , Kindle Christopher , Schlater Jordan , Hays Joseph T. , Feerst Phillip A. , Wereley Norman
Published: December 2019

The U.S. Naval Research Laboratory (NRL) has been developing a space-rated 7 degree of freedom (DOF) robot arm with a high payload-to-mass ratio as an alternative design to motor-gear driven robotic manipulators. The robot arm employs antagonistic pairs of pneumatic artificial muscle (PAM) actuators to control each degree-of-freedom (DOF) to achieve large force outputs relative to the PAM component masses. A novel feature of the NRL PAM actuator was the integration of the pneumatic control components inside the pressure-bladder, which not only reduces the volume of the robotic arm hardware but also reduces the pressurized-gas actuation volume in the PAM enabling significant reductions in gas consumption during actuation. This multifunctional design enables reductions in launch-weight costs and increases in operational endurance for space applications. The integration of these PAMs into a well-designed robotic-arm structure, in tandem with a newly developed control algorithm, has the potential to exceed the performance metrics of traditional motor-driven robot arms. This paper describes the development of the improved efficiency PAM design that is advancing this technology towards space flight readiness.
3D Printed Segmented Flexible Pneumatic Actuator
Authors: Gonzalez David , Garcia Jose , Newell Brittany
Published: December 2019

Soft actuators have been studied and analyzed as a new solution for soft robotic technologies. These types of actuators have many advantages due to their predictable deformations and their ease of control, enabling them to hold and move delicate objects performing complex movements in confined spaces. Soft actuators can be made using different manufacturing processes, but the most common is mold casting. However, this manufacturing process involves several steps, increasing the manufacturing time and hindering changes in the design. This paper presents a novel design of a 3D printed soft pneumatic actuator based on additive manufacturing, achieving design versatility and performance. The produced actuator has seven that can be individually controlled. The actuators were made using fused deposition modeling (FDM) technology in one continuous process and without support material. The mechanical performance of the soft actuators was demonstrated, analyzing the deformation in the z-axis based on input pressure.
Preliminary Experimental Investigation of Control Parameters for the Electroresistive Heating of SMA Knitted Textiles
Authors: Marbaker Rachel , Utter Brent , Eschen Kevin , Abel Julianna
Published: December 2019

Knitted textiles manufactured from shape memory alloy (SMA) monofilaments possess advanced capabilities for distributed and complex actuation and are suited for a range of emerging needs in aerospace, biomedical, and robotics applications. In general, high currents for short periods of time provide sufficient electroresistive (Joule) heat to cause SMA wires to transform to austenite. However, SMA knitted textiles are difficult to electroresistively heat because the interlocking knit structure short-circuits the flow of current, causing localized overheating and isolating the transformation of the material along the current path. One approach for heating SMA knitted textiles is to drive pulses of high current between pairs of electrodes positioned across horizontal courses (rows) of knitted loops. This research presents a preliminary experimental investigation of the effects of factors related to electroresistive heating for SMA knitted textiles. A design of experiments analysis with two levels of four factors was conducted using a 24–1 fractional factorial design. The factors included the voltage of the power supply connected to the current amplifiers; a geometric factor defining the horizontal spacing of the electrodes attached to the knit sample; and two waveform factors: On Cycles and Off/On Cycles, which defined the length of time each current amplifier was enabled and disabled. Actuation performance was quantified by the actuation displacement and actuation force of the knit sample. Preliminary results suggest that voltage is the most influential factor, but also indicate that interactions between the geometric and waveform factors have significant effects on the heating and actuation performance. The characterization of these factor interactions has the potential to inform optimal electroresistive heating approaches for SMA knitted textiles, enabling integration into applications such as wearable technologies where convective heating is not practical.
Woven Nitinol Fabric Strips Characterized in Tension via Finite Element Analysis and Geometric Modeling
Authors: Skalitzky Amanda , Petersen Caleb , Gurley Austin , Beale David
Published: December 2019

Nitinol in the form of wires, tubes, and plates have been explored extensively; however, the characteristics of Nitinol as a woven fabric have so far been little-studied analytically. It would be easier to design such a fabric if conventional fabric models were known to apply to Nitinol fabrics, potentially with modifications required by Nitinol’s unique properties. A 25 mm wide Nitinol narrow fabric has been manufactured using traditional weaving equipment using a proprietary process that achieves a uniform and tight weave. Heat-treatment and straight shape-set is applied to a single Nitinol wire and the woven Nitinol fabric at 600°C for 30 minutes. The 0.25 mm Nitinol wire constituent was tested using differential scanning calorimetry (DSC) to determine the transition temperatures (Mf, Ms, As, and Af), which were found on average to be 54.5°C, 66.9°C, 88.7°C, and 103.5°C respectively. Both the Nitinol wire and fabric were tested in a temperature-controlled chamber (testing temperatures ranged from room temperature to 200°C) in which the tensile stress-strain characteristics were observed. It was determined that existing analytical models can be employed to accurately estimate the overall tensile stiffness of woven Nitinol fabrics in a small-strain regime. Additionally, it was confirmed that the tensile loading of woven Nitinol fabric can be modeled in MSC.Adams with beam elements. In combination with the geometric model presented, woven Nitinol fabric behavior can be predicted from the experimental behavior of the constituent Nitinol wire.
Smart Material Actuation of Multi-Locomotion Robot
Authors: Jovanova Jovana , Domazetovska Simona , Changoski Vasko
Published: December 2019

The focus of this research is modeling, simulation and prototyping of multi-locomotion bio-inspired robot. The actuation is based on shape memory alloys (SMAs) smart materials to achieve different styles of movements. Soft-bodied robots have potential to exploit morphological computation to adapt and interact with reduced control complexity. Observing the movement of a caterpillar that could produce different locomotion such as crawling and rolling, our team designed and developed a bio-inspired robot.

Analytical models of the different bio-inspired movements are derived and analyzed in Matlab in this work. The models rely on segmented approach actuated by smart materials in order to achieve the desired position. Smart material actuators are a promising but challenging actuation mechanism because of their design, large deformation possibilities, external stimuli shape change and high power density. The body parts are from a soft silicon elastomer. Between the silicone body parts, SMA spring are embedded, used as actuation force. Between the two segments, SMA spring as actuators are generation strain to bend the body and achieve crawling and lifting.

This work is initial modeling for multi locomotion of soft bio-inspired robot and will be followed by a detailed analytical and numerical modeling and simulation, finalizing with a functional prototype.
Experimental Technique to Estimate Interfacial Properties of Mechanoluminescent Particles in an Elastomer Matrix
Authors: Krishnan Srivatsava , Katsube Noriko , Sundaresan Vishnu baba
Published: December 2019

Mechanoluminescent-particulate filled composites have been gaining significant interest for light generation, stress visualization, health monitoring, damage sensing and pressure mapping applications. Previous works on stress-dependence of light emission have modeled emission intensity as a function of macroscopic composite stress. While this approach may suffice from an application point of view, the resulting model may not represent the mechanoluminescence phenomenon accurately. This is because in particulate filled elastomer composites, particulate stresses can be significantly different from matrix and macroscopic stresses, especially in composites with moderate and low filler volume fraction. Experimental difficulty in measuring stresses within micron-sized particles necessitate micromechanical models that can connect macroscale measurements to microscale parameters through material properties. Apart from the material properties of the matrix and the particles, the bonding between the two dissimilar materials at their interface influences the stress transfer significantly. Cohesive zone modeling (CZM) approach defines the interface between particles and matrix as a piecewise linear stiffness element with possible degradation of stiffness beyond a certain strain. CZM provides a convenient way to not only predict particulate stress from macroscopic stress, but also to track interface damage and debonding. In this paper, we demonstrate an experimental technique to obtain cohesive zone parameters for mechanoluminescent-particulate filled elastomer composites, utilizing optical microscopy and Digital Image Correlation (DIC). CZM thus obtained can help predict particulate stresses and aid better modeling of the mechanoluminescence phenomenon. The experimental technique can also be easily adopted for other particulate-filled composites.
Perceived Value Change via 3D Printed Bistable Structures
Authors: Chan Wan Kyn , Riley Katherine S. , Arrieta Andres F.
Published: December 2019

A key aspect of color change is altering perceived value or intensity. This paper presents a methodology to achieve value change through mechanical means via the deflection of bistable structures. We create mechanical pixel-based, reversible color change using 3D printed switchable bistability. Switchable bistability arises from the combination of pre-strain and shape memory, enabling us to access multiple elastically programmed shapes at elevated temperatures with fast morphing and low actuation forces, while retaining high stiffness at room temperature. Building on our previous study that achieved bistability through FDM printing with directional pre-stress, finite element analysis is conducted to design a pixel-like structure that acts as a unit cell with color change capabilities. Quantitative and qualitative analysis is conducted through image processing techniques in order to prove the viability of this approach to creating value change through geometric deformation of bistable structures. By leveraging this technique, there are numerous potential applications in fields including robotics, architecture, and interior design.
Direct Printing of a Flexible Strain Sensor for Distributed Monitoring of Deformation in Inflatable Structures
Authors: Al-Rubaiai Mohammed , Tsuruta Ryohei , Nam Taewoo , Gandhi Umesh , Tan Xiaobo
Published: December 2019

Inflatable structures provide significant volume and weight savings for future space and soft robotic applications. Structural health monitoring (SHM) of these structures is essential to ensuring safe operation, providing early warnings of damage, and measuring structural changes over time. In this paper, we propose the design of a single flexible strain sensor for distributed monitoring of an inflatable tube, in particular, the detection and localization of a kink should that occur. Several commercially available conductive materials, including 3D-printing filaments, conductive paint, and conductive fabrics are explored for their strain-sensing performance, where the resistance change under uniaxial tension is measured, and the corresponding gauge factor (GF) is characterized. Flexible strain sensors are then fabricated and integrated with an inflatable structure fabric using screen-printing or 3D-printing techniques, depending on the nature of the raw conductive material. Among the tested materials, the conductive paint shows the highest stability, with GF of 15 and working strain range of 2.28%. Finally, the geometry of the sensor is designed to enable distributed monitoring of an inflatable tube. In particular, for a given deformation magnitude, the sensor output shows a monotonic relationship with the location where the deformation is applied, thus enabling the monitoring of the entire tube with a single sensor.
Phase Inversion of Complex Fluids With Implications to Drilling Fluids
Authors: Numkam Gilles , Akbari Babak
Published: December 2019

Global energy demand continues to drive oil and gas exploration in increasingly challenging environments. The extreme temperatures and pressures drilling fluids are subjected to require optimum design of their rheology. Among the numerous components used in the design of drilling fluids are surfactants. Surfactants play an important role in the emulsification of immiscible liquids as well as the alteration of cuttings wettability to facilitate transport to the surface.

Nonionic surfactants, depending on their chemical group allow the inversion of oil-in-water emulsions (O/W) to water-in-oil (W/O) and vice-versa depending on the direction of temperature change. In this study, emulsion-suspension samples were prepared with different nonionic surfactants at Oil:Water ratios of 50:50 and 60:40. The mechanical properties of the samples was assessed using a scientific rheometer at temperatures ranging from 0–90 °C.

Phase inversion from oil-in-water to water-in-oil was observed for samples stabilized by polyoxyethylene oleyl ether surfactants. Build up in the apparent viscosity of the samples was observed following phase inversion, mainly resulting from the formation of nanosized dispersed water droplets.

Findings in the study highlighted the possibility of obtaining different drilling fluid types during downhole circulation, thereby paving a path for the design optimization of drilling fluids used in offshore operations.
Totipotent Cellularly-Inspired Materials
Authors: Mattern-Schain Samuel I. , Nguyen Mary-Anne , Schimel Tayler M. , Manuel James , Maraj Joshua , Leo Donald , Freeman Eric , Lenaghan Scott , Sarles Stephen A.
Published: December 2019

This work draws inspiration from totipotent cellular systems to design smart materials whose compositions and properties can be learned or evolved. Totipotency refers to the inherent genetic potential of a single cell to adapt and produce all types of differentiated cells within an organism. To study this principal and apply it synthetically, tissue-like compartmentalized assemblies are constructed via lipid membrane-separated aqueous droplets in a hydrophobic medium through the droplet interface bilayer (DIB) method. Within our droplets, we explore synthetic totipotency via cell-free reactions including actin polymerization and cell free protein synthesis (CFPS). The transcription and translation of our CFPS reactions are controlled by stimuli-responsive riboswitches (RS). Via this scheme, adaptable material properties and functions are achieved in vitro via protein production from cell-free machinery administered through RS governance. Here, we present thermally or chemically-triggered riboswitches for orthogonal production of representative fluorescent protein products, as well functional proteins. To characterize the material properties of target proteins, we study the formation of polymerized actin shells to stabilize organically-encased droplets and span DIBs. We present a modified protocol for chemically-triggered actin polymerization as well as a thermally triggered actin RS. We characterize theophylline (TP)-triggered production of alpha hemolysin (α-HL) through CFPS and synthesized an organic-soluble trigger that can be sensed from the oil phase by a RS in an aqueous bioreactor droplet. We also demonstrate increased droplet conductivity when CFPS α-HL products are incorporated in DIBs. This interdisciplinary work involves cell culture, gene expression, organic synthesis, vesicle formation, protein quantification, tensiometry, droplet aspiration, microplate fluorescence/absorption experiments, fluorescent microscopy, and electrophysiology. This project is an essential design analysis for creating smart, soft materials using synthetic biology and provides motivation for artificial tissues capable of adapting in response to external stimuli.
The Effects of Lower-Extremity Plyometric Training on Soccer-Specific Outcomes in Adult Male Soccer Players: A Systematic Review and Meta-Analysis
Authors: van de Hoef Peter A. , Brauers Jur J. , van Smeden Maarten , Backx Frank J.G. , Brink Michel S.
Published: December 2019

Background: Plyometric training is a specific form of strength training that is used to improve the physical performance of athletes. An overview of the effects of plyometric training on soccer-specific outcomes in adult male soccer players is not available yet. Purpose: To systematically review and meta-analyze the effects of plyometric training on soccer-specific outcome measures in adult male soccer players and to identify which programs are most effective. Methods: PubMed, Embase/Medline, Cochrane, PEDro, and Scopus were searched. Extensive quality and risk of bias assessments were performed using the Cochrane ROBINS 2.0 for randomized trials. A random effects meta-analysis was performed using Cochrane Review Manager 5.3. Results: Seventeen randomized trials were included in the meta-analysis. The impact of plyometric training on strength, jump height, sprint speed, agility, and endurance was assessed. Only jump height, 20-m sprint speed, and endurance were significantly improved by plyometric training in soccer players. Results of the risk of bias assessment of the included studies resulted in overall scores of some concerns for risk of bias and high risk of bias. Conclusion: This review and meta-analysis showed that plyometric training improved jump height, 20-m sprint speed, and endurance, but not strength, sprint speed over other distances, or agility in male adult soccer players. However, the low quality of the included studies and substantial heterogeneity means that results need to be interpreted with caution. Future high-quality research should indicate whether or not plyometric training can be used to improve soccer-specific outcomes and thereby enhance performance.
Paroxysmal slow cortical activity in Alzheimer’s disease and epilepsy is associated with blood-brain barrier dysfunction
Authors: Milikovsky Dan Z. , Ofer Jonathan , Senatorov Vladimir V. , Friedman Aaron R. , Prager Ofer , Sheintuch Liron , Elazari Netta , Veksler Ronel , Zelig Daniel , Weissberg Itai , Bar-Klein Guy , Swissa Evyatar , Hanael Erez , Ben-Arie Gal , Schefenbauer Osnat , Kamintsky Lyna , Saar-Ashkenazy Rotem , Shelef Ilan , Shamir Merav H. , Goldberg Ilan , Glik Amir , Benninger Felix , Kaufer Daniela , Friedman Alon
Published: December 2019

Transient EEG slowing events are shared by patients and models of Alzheimer’s and epilepsy and are associated with blood-brain barrier dysfunction.
Orogenic link ∼41°N–46°N: Collisional mountain building and basin closure in the Cordillera of western North America
Authors: Gray Keith D. , Isakson V. , Schwartz D. , Vervoort Jeffrey D.
Published: December 2019

Polyphase structural mapping and mineral age dating across the Salmon River suture zone in west-central Idaho (Riggins region; ∼45°30′N, ∼117°W–116°W) support a late Mesozoic history of penetrative deformation, dynamothermal metamorphism, and intermittent magmatism in response to right-oblique oceanic-continental plate convergence (Farallon–North America). High-strain linear-planar tectonite fabrics are recorded along an unbroken ∼48 km west-to-east transect extending from the Snake River (Wallowa intra-oceanic arc terrane; eastern Blue Mountains Province) over the northern Seven Devils Mountains into the lower Salmon River Canyon (ancestral North America; western Laurentia). Given the temporally overlapping nature (ca. 145–90 Ma) of east-west contraction in the Sevier fold-and-thrust belt (northern Utah–southeast Idaho–southwest Montana segment), we propose that long-term terrane accretion and margin-parallel northward translation in the Cordilleran hinterland (∼41°N–46°N latitude; modern coordinates) drove mid- to upper-crustal shortening >250 km eastward into the foreland region (∼115°W–113°W). During accretion and translation, the progressive transfer of arc assemblages from subducting (Farallon) to structurally overriding (North American) plates was accommodated by displacement along a shallow westward-dipping basal décollement system underlying the Cordilleran orogen. In this context, large-magnitude horizontal shortening of passive continental margin strata was balanced by the addition of buoyant oceanic crust—late Paleozoic to Mesozoic Blue Mountains Province—to the leading edge of western Laurentia. Consistent with orogenic float modeling (mass conservation, balance, and displacement compatibility), diffuse dextral-transpressional deformation across the accretionary boundary (Salmon River suture: Cordilleran hinterland) was kinematically linked to eastward-propagating structures on the continental interior (Sevier thrust belt; Cordilleran foreland). As an alternative to noncollisional convergent margin orogenesis, we propose a collision-related tectonic origin and contractional evolution for central portions of the Sevier belt. Our timing of terrane accretion supports correlation of the Wallowa terrane with Wrangellia (composite arc/plateau assemblage) and implies diachronous south-to-north suturing and basin closure between Idaho and Alaska.
Development of a prediction model to aid primary care physicians in early identification of women at high risk of developing endometriosis: cross-sectional study
Authors: Verket Nina Julie , Falk Ragnhild Sørum , Qvigstad Erik , Tanbo Tom Gunnar , Sandvik Leiv
Published: December 2019

Objectives

To identify predictors of disease among a few factors commonly associated with endometriosis and if successful, to combine these to develop a prediction model to aid primary care physicians in early identification of women at high risk of developing endometriosis.

Design

Cross-sectional anonymous postal questionnaire study.

Setting

Women aged 18–45 years recruited from the Norwegian Endometriosis Association and a random sample of women residing in Oslo, Norway.

Participants

157 women with and 156 women without endometriosis.

Main outcome measures

Logistic and least absolute shrinkage and selection operator (LASSO) regression analyses were performed with endometriosis as dependent variable. Predictors were identified and combined to develop a prediction model. The predictive ability of the model was evaluated by calculating the area under the receiver operating characteristic curve (AUC) and positive predictive values (PPVs) and negative predictive values (NPVs). To take into account the likelihood of skewed representativeness of the patient sample towards high symptom burden, we considered the hypothetical prevalences of endometriosis in the general population 0.1%, 0.5%, 1% and 2%.

Results

The predictorsabsenteeism from school due to dysmenorrheaandfamily history of endometriosisdemonstrated the strongest association with disease. The model based on logistic regression (AUC 0.83) included these two predictors only, while the model based on LASSO regression (AUC 0.85) included two more:severe dysmenorrhea in adolescenceanduse of painkillers due to dysmenorrhea in adolescence. For the prevalences 0.1%, 0.5%, 1% and 2%, both models ascertained endometriosis with PPV equal to 2.0%, 9.4%, 17.2% and 29.6%, respectively. NPV was at least 98% for all values considered.

Conclusions

External validation is needed before model implementation. Meanwhile, endometriosis should be considered a differential diagnosis in women with frequent absenteeism from school or work due to painful menstruations and positive family history of endometriosis.