bluuebunny/crossref_metadata_2025_split huggingface dataset:
Food Waste to Feed-Stock Chemicals, Using Microbial Consortia and Bio-Hybrid Fuel Cells
Authors: Mackie David Mark , Jahnke Justin P. , Benyamin Marcus S. , LeFors Hannah M. , Sund Christian J. 
Published: February 2020

Some microorganisms secrete abundant amounts of diverse enzymes, either naturally or through genetic engineering, that can break down components of food waste (or biomass generally). Simple sugars are thereby produced in solution, where fast-fermenting microorganisms can metabolize them much faster than the secretory microorganisms, producing biofuels. (For example, consortia of the mold Aspergillus oryzae and the yeast Saccharomyces cerevisiae on uncooked rice achieve concentrations of 13% ethanol in 10 days at room temperature.) Secretor-fermenter consortia can be directly coupled with fuel cells (FCs), producing electricity and feedstock chemicals. However, long-term operation of such “bio-hybrid FCs” (BHFCs) requires strictly preventing the microorganisms and FC from harming themselves and each other. This can be accomplished by using gas stripping to continually and selectively extract the (volatile) biofuel from the fermentation medium, and to vapor-feed the FC. This protects the FC from the (non-volatile) catalyst poisons in the fermentation. This also protects the consortium from any harmful FC products (e.g., acetic acid) and from build-up of biofuels, which are inhibitory at high concentrations. We first show that power densities for vapor-fed direct ethanol fuel cells (DEFCs) are comparable to those for liquid-fed DEFCs, with power densities greater than 2 mW/cm2 obtained (orders of magnitude higher than microbial FCs). We then show that mold-yeast-DEFC BHFCs fueled with glucose (or rice) can operate for long periods with no maintenance other than adding water and food. With the right conditions and DEFC, the effluent can be acetic acid at high concentrations and with few impurities. Other effluents from BHFCs are possible, depending on the organisms, food, and FC.
(Invited) The Biotic/Abiotic Interface between Neuromodulation Electrodes and the Peripheral Nervous System
Authors: Wolfson Michael B. 
Published: February 2020

This introductory talk will provide background on the anatomy and biological environment of the peripheral nervous system and spinal cord. Building from this foundation, a variety of approaches to build electrical interfaces capable of interacting with tissue will be reviewed. These interfaces typically fall into four major categories: metal alloys, conductive inorganic non-metals, conductive polymers, and capacitive transduction through a dielectric. The requirements for recording neuronal activity are distinct from those for stimulating activity due to the challenges of working in an ionic environment. Information in the nervous system is represented not by the presence of electrons and holes, but by the physical transport of elemental ions within and between cells. By understanding the limitations, constraints, and tradeoffs of current approaches in context of the biological environment, it is possible to envision new opportunities to increase the reliability, safety, and functionality of tissue interfaces.
The remainder of the talk will provide insight into the National Institutes of Health (NIH), its various funding opportunities, and how grant applications are evaluated and funded. Although all federal funding agencies serve the same fundamental purpose, the mission of each is substantially different, which directly shapes its operations and processes. After a “big picture” of NIH funding is presented, a deep dive will be provided on the National Institute of Biomedical Imaging and Bioengineering and the Office of Strategic Coordination’s Common Fund. Several programs within those organizations will be described, including: Advanced Biomaterials, Implantable Medical Devices, and Stimulating Peripheral Activity to Relieve Conditions (SPARC). While the concept of peer review is familiar to all, the NIH implementation of this process has unique nuances that will be described. Finally, suggestions will be provided for investigators on how to best engage with the NIH in pursuit of addressing unmet medical needs.
(Invited) Using Electrochemical Measurements to Diagnose Neural Interface Electrodes
Authors: Troyk Philip , DeMichele Glenn 
Published: February 2020

The sophistication of neuroscience experiments designed to elucidate the functionality of the mammalian central and peripheral nervous system is rapidly increasing, and so must the use of more complex electrodes that are used to interrogate the behavior of neural networks. Despite the rapid rise of optical techniques, the metal microelectrode remains the workhorse of experimental neuroscience, and implantable electrode arrays continue to be an important experimental tool. Unfortunately, the reliability of multielectrode arrays remains marginal. While some researchers have been able to record neural activity for many months, or years, more commonly the neuroscientist is hampered by short-term degradation in electrode insulation, increasing array electrical leakage, breakage of wires, and failure of percutaneous connectors. Often these failures obscure the neuroscience experimental goals, and the neuroscientist is left to guess whether changes in data are due to array deficiencies or biological effects.
Initiated by a DARPA grant, our group has developed a microelectrode array analytic and diagnostic instrument that can assess the “health” of implanted electrode arrays. Using a combination of CV, EIS, and pulsed-current measurements, the multiple electrode array analyzer uses 16 parallel potentiostatic modules to perform these measurement modalities in parallel, rather than multiplexing a single instrument. This parallel measurement capability is important because the duration of sessions with experimental animals is often very limited, and the researcher is unable to dedicate a significant portion to merely determining the status of the implanted electrodes. Parallel measurement of 16 electrodes dramatically reduces the time required to diagnose the condition of implanted electrodes at the onset of an experimental session. However, performing parallel measurements of CV and EIS for multiple electrodes pose unique instrumentation challenges that have been addressed in our design.
The performance of this instrument has been evaluated in experiments performed on Macaque with electrode arrays implanted in the brain in a location that is particularly vulnerable to cable breakage. Diagnoses of the electrodes, and connection system, have been performed that clearly show increased electrical leakage as differentiated from biological encapsulation of the electrode tips. The presentation will describe these experiments, the electrochemical data, and the functional diagnoses.
Our long-term goal is the development and distribution of a diagnostic software module which permits frequent and rapid collection of in-vivo electrode electrochemical data, with the option of upload to a central database for sharing among researchers. Using this diagnostic means, the researcher can anticipate electrode array failures, and make appropriate experimental decisions.
Fabrication of Magnetostrictive Nano-Tubes/Bar As Sensor Plaform
Authors: Zheng ZhiZhi , Cheng Z.-Y. , Zhang Kewei 
Published: February 2020

Acoustic wave devices have been used as sensor platforms for the development of biological sensors, in which the surface of the acoustic wave device is coated with a layer of biomolecular recognition unit such as phage and antibody. The sensitivity and many other characteristics of the acoustic wave device based sensors are dependent on the size of the device. The smaller the size of the acoustic wave device is, the higher the sensitivity of the sensor is. Therefore, it is highly interested to fabricate the acoustic wave devices with a smaller size, such as micro/nano-sized devices. It has been experimentally demonstrated that the acoustic wave devices based on the magnetostrictive effect have many advantages over the acoustic wave devices base on effect. For example, the acoustic wave devices based on magnetostrictive effect can be operated wirelessly/remotely, which is very critical, especially for micro/nano-sized acoustic wave devices.
Electrochemical deposition is used to fabricate the magnetostrictive Co-Fe-B alloy in different shapes and sizes. In this presentation, the process to fabricate the nano-sized magnetostrictive Co-Fe-B tubes and bars is reported. The properties of the nano-tubes/bars are characterized and discussed in this presentation. Based on the experimental results, the fabrication process (i.e. the solution concentration, solution temperature, deposition current, and deposition time) is optimized to achieve a high magnetostriction and a quality merit factor.
Rapid Detection of Bacterial Pathogens on 2D Food
Authors: Xi Jianguo , Horikawa Shin , Chen I-Hsuan , Liu Yuzhe , Du Songtao , Lu Xu , Wikle Howard Clyde , Suh Sang-Jin , Chin Bryan A 
Published: February 2020

This paper investigates a rapid method of detecting bacterial pathogens on 2D food, such as leafy greens. The method is based on our previous work that uses freestanding phage-coated magnetoelastic (ME) biosensors and a surface-scanning coil detector for direct bacterial detection on the surface of food without commonly used sample preparation steps (washing, concentration, enrichment, etc). The ME biosensors used in this work were ferromagnetic alloy strips coated with E2 phage that specifically binds with Salmonella Typhimurium. First, the biosensors (1 mm × 0.2 mm × 30 µm) were placed in rectangular, indexed cavities (1.1 mm × 0.22 mm × 20 µm) that are etched in a glass wafer. A sheet magnet was added to the back of the wafer to hold the sensors in place. The glass wafer with the biosensors and sheet magnet was then flipped and lowered onto Salmonella-tainted spinach leaves. At this time, a weight was added such that the leaves got flattened to improve the chance for the biosensors to physically contact with Salmonella cells. Various weights ranging from 0 g to 120 g were tested to investigate their effects on the Salmonella binding.
Measurement sensors loaded with E2 phage and control sensors devoid of the phage were prepared and used. The control sensors served as the reference to compensate for the environmental effects such as temperature and humidity. The biosensors were placed on the surface of the spinach leaves for 2 mins for the binding to occur. The degree of the binding of Salmonella to the measurement sensors was determined by measuring the resonant frequency shift of the sensors using a surface-scanning detection system and confirmed by optical microscopy. The binding of Salmonella was found to increase as the spiked Salmonella concentration increased (103 cfu/ml to 108 cfu/ml). In addition, significant resonant frequency shifts of the measurement sensors (4,800 ± 160 Hz) were observed when 60 g of weight was added. However, further increases in weight did not improve the Salmonella binding with E2 phage. Rather, heavier weights increased the probability of non-specific attachment of Salmonella cells and other residuals from the leaf surface.
Detection and Subtyping of Salmonella from Raw Chicken through Targeted Salmonella Capture, Genome Amplification and Whole Genome Sequencing
Authors: Hyeon Ji-Yeon , Li Shaoting , Chin Bryan A , Deng Xiangyu 
Published: February 2020

The often low abundance and uneven distribution of bacterial foodborne pathogens in food samples makes rapid, sensitive and specific detection of these pathogens an enduring challenge. Selective concentration of a target organism is often required to bring pathogen cells to a detectable level for subsequent analyses. For example, culture enrichment is still the most widely used method in spite of its lengthy process (i.e., more than 12 hours) that is intrinsically restricted in speed by the length of cell cycle.
Alternative concentration approaches to culture enrichment have been developed. For instance, immunomagnetic separation (IMS) has been applied to certain food matrices. In addition to enriching bacterial cells, amplification of bacterial genomes, for instance, through multiple displacement amplification (MDA), has been shown to facilitate molecular detection of difficult-to-culture pathogens from clinical samples.
We have recently shown that by concatenating IMS, MDA and real-time PCR, we could detect low levels of Salmonella enterica (~10 CFU/g) in raw chicken breast without culture enrichment (Hyeon and Deng, Food Microbiology, 2017)
In this study, we aimed to develop a workflow that consists of 1) specific concentration of Salmonella cells, 2) high-efficiency amplification of bacterial genomes, and 3) molecular detection of Salmonella. The modular design of this workflow allows customized combination of different sample processing and detection methods to meet specific detection need for speed, sensitivity or specificity. In particular, we will demonstrate that the use of a novel magnetoelastic biosensor (Chai et al., Journal of Food Protection, 2012) and whole genome sequencing (WGS) can allow strain-level identification of Salmonella from raw chicken with no or shortened culture enrichment.
(Invited) Spectral Imaging and Instrumentation for Food Safety Evaluation of Agricultural Products
Authors: Kim Moon Sung 
Published: February 2020

Researchers at the Beltsville Agricultural Research Center have developed spectral-image-based sensing systems and techniques to reduce food safety risks in post-harvest production and processing. The research objectives focus primarily on comprehensive safety and quality inspection for online bulk processing of fresh fruits and leafy greens, authentication of food ingredients and detection of food contaminants, and improvement of cleaning and sanitation efficacies in food processing facilities. For improved online produce screening, imaging methods and prototype instrumentation have been developed to allow for inspection of whole surfaces of round fruits and relatively flat leafy greens. The prototype produce inspection systems incorporate multi-view and multitask imaging methods for simultaneous reflectance and fluorescence imaging, thus allowing for screening of nearly 100% of the surface areas for fecal contaminants and defects during processing. To detect adulterants, a high throughput line-scan Raman imaging system was developed to rapidly scan large surface areas of food ingredients (e.g., milk powder) for adulterants. In addition, a fluorescence-based handheld imaging technology for contamination detection has been optimized for various commercial applications, such as contamination and sanitation inspection in meat and produce processing facilities. Collectively, these instrumentation and spectral-image-based sensing systems will facilitate rapid, non-destructive detection of contaminants or adulterants in food. The current states of the above spectral imaging and instrumentation technologies are presented.
Photo-Reduced Graphene As Electrode Active Materials for Supercapacitor Applications
Authors: Yang Dongfang 
Published: February 2020

Supercapacitors are among the most promising energy storage devices due to their high power density, short recharging time, long cycle life, as well as environmental friendliness. Supercapacitors with increased energy densities are needed for practical applications such as plug-in hybrid electric vehicles, wind turbine energy storage, regenerative breaking, cold starting of trucks and space exploration applications. Supercapacitors store energy using either ion adsorption (electrochemical double layer capacitors) or fast surface redox reactions (pseudo-capacitors). Electrochemical double layer capacitors use the high surface area of carbon, such as activated carbon, carbon fiber and graphene, as the electrode active materials, while metal oxides and electronically conducting polymers are used as the electrode active materials for pseudo-capacitors. Graphene is a form of carbon that has substantially higher surface area than the more common electrode active material, activated carbon, and thus potentially allows for more storing of electrostatic charge. The high electrical conductivity and planar structure of graphene also gives rise to fast charging and discharging. In this presentation, recent development on the fabrication of graphene by means of photo reduction of graphene oxide will be given. The photo reduction creates a disordered corrugated graphene structure in which adjacent sheets are no longer oriented parallel to each other. As an example, the performance of excimer laser reduced graphene and N-doped graphene when it is used as electrode active materials in supercapacitors was evaluated in both aqueous and organic electrolytes at room temperature. By varying the laser irradiation processing conditions such as laser energy and irradiation time, graphene and N-doped graphene with different supercapacitive behaviors were successfully grown. The specific capacitance of laser reduced graphene reaches 120 F/g at 5mV/sec in the aqueous electrolyte. Highly conductive N-doped graphene can be prepared by adding NH3 into graphene oxide solution during laser photo-reduction process and the doped graphene has slightly reduced specific capacitance of 110 F/g at 5 mV/sec in 0.5 M K2SO4 aqueous electrolyte. This work demonstrated that excimer laser irradiation process is a very promising technique for preparation of graphene and N-doped graphene for its use as the electrode active material for supercapacitors due to its excellent flexibility and capability of controlling microstructures, electric conduction and specific capacitance.

Figure 1
All-Solid-State Supercapacitor Based on Graphene Oxide Composite Electrodes
Authors: Lo Hsin-Ju , Chen Hsun-Yi 
Published: February 2020

Supercapacitors and lithium ion batteries combined are promising hybrid energy storage for portable products, electric vehicles, and smart grid applications. However, the major scientific challenge in this system is to significantly increase the energy density of supercapacitors or raise the power density of lithium ion battery to enhance flexibility for various energy demands.
This study aims to extend the energy density while maintain high specific capacitance through modification of electrodes with graphene oxide (GO) based materials. To prevent leakage of electrolyte, gel polymer electrolyte (GPE) consisting of lithium salt is selected, and it is also able to enhance the mechanical property of the capacitor. GO synthesized by chemical methods from graphite powder is employed because chemically functionalized surface of GO sheet can exhibit derived hydroxyl groups, epoxy groups, and active edges with carboxylic acid groups. Engineering of these functional groups in GO can potentially affect the surface adsorption and in turn improve the performance of capacitors.
In this study, modification of GO surface is conducted and its effects on the all-solid-state supercapacitor are investigated. Characterizations of functionalized graphene oxide have been conducted with x-ray diffraction (XRD), scanning electron microscopy (SEM), and FTIR. Electrochemical performance of these electrodes is investigated using cyclic voltammetry, galvanostatic charge-discharge, and electrochemical impedance spectroscopy.
Low Cost Rapid Synthesis of Exfoliated Graphite Containing Manganese Oxide Materials for Energy and Environmental Applications
Authors: Sykam Nagaraju , G Mohan Rao 
Published: February 2020

Carbon materials play considerable role towards energy and environmental applications in a fast growing world. Energy storage and waste water treatment are the two major challenges in the global scenario. Exfoliated graphite, a worm like highly porous carbon nanostructured material exhibits excellent properties and is a potential candidate for many applications. Here, we report rapid and efficient preparation of exfoliated graphite with manganese oxide materials by using microwave irradiation technique, which is one of the most efficient energy sources. The as prepared material was characterized by X-ray diffraction analysis (XRD), field emission scanning electron microscopy (FESEM) and fourier transform infrared spectroscopy (FTIR) techniques. The material showsexcellent electrochemical performance with high specific capacitance value of 166.6 F/g at a current density of 1 A/g under 1M Na2SO4 electrolyte solution. Also, the material shows unusual removal performance of various organic dyes such as congo red (CR) and indigo carmine (IC) from water. The effect of process parameters i.e., pH, contact time, and initial dye concentration on removal of dyes under aqueous solutions was investigated. The adsorption isotherms (Langmuir model), kinetics models (pseudofirst and pseudo-second-order) were used to study the dye adsorption mechanism. It is suggested that the mechanism of adsorption depends mainly on the random distribution of pores, as well as, surface area. The maximum adsorption capacity reaches 222.2 and 204.1 mg/g for IC and CR dyes at equilibrium under aqueous solutions.
Keywords: Carbon materials, porous materials, exfoliated graphite, adsorption, supercapacitors.
Evaluation of Performance and Degradation Profiles of a Metal Supported Solid Oxide Fuel Cell under Electrolysis Operation
Authors: Nechache Aziz , Han Feng , Semerad Robert , Schiller Guenter , Costa Rémi 
Published: February 2020

In this context of energy transition, the use of renewable energies through the conversion of different resources with promising technologies into storable energy carriers is of eminent importance for a sustainable energy supply. Hydrogen production from steam using solid oxide electrolysis cells (SOEC) is part of this so called “energy mix”. Recently, promising progress appeared from the investigation of metal supports in the solid oxide cell architecture. Metal-supported solid oxide fuel cells (MS-SOFCs) show not only good mechanical strength, relatively low operating temperature (500-750 °C) and improved sealing capability but also low materials cost and tolerance towards rapid thermal cycling and redox cycling [1-3]. In the present study, a MS-SOFC was tested under electrolysis conditions. The cell consisted of Ni-catalyst-loaded La0.1Sr0.9TiO3-α/gadolinium-doped ceria (Ni-LST/GDC) as fuel electrode, gadolinium-doped ceria/yttrium-stabilized zirconia (GDC/YSZ) as electrolyte and La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF) as O2 electrode. After a short testing period in fuel cell mode, a first evaluation of the cell performance profile in electrolysis mode was performed. Thus, a series of current-voltage curves as well as impedance diagrams (under OCV and under load) was recorded for different fuel electrode gas compositions. Furthermore, degradation under electrolysis operation was also investigated based on the evolution of the cell voltage against time for several currents applied. Consequently, analysis of the post-mortem characterization by SEM/EDX, along with the electrochemical testing results, aims at identifying the changes in cell characteristics specifically related to degradation under electrolysis operating conditions.
[1] M. C. Tucker, J. Power Sources 195 (2010) 4570-4582.
[2] J. T.S. Irvine, J. Bae, J-Y Park, W. S. Choi, J. H. Kim, Int. J. Hydrogen Energy, In Press-Corrected Proof.
[3] A. M. Dayaghi, K. J. Kim, S. Kim, J. Park, S. J. Kim, B. H. Park, G. M. Choi, J. Power Sources 324 (2016) 288-293.