bluuebunny/crossref_metadata_2025_split huggingface dataset:
Biaxial, Hybrid Plastic-Elastic Relaxation in Micropatterned Semipolar InGaN Buffer Layers Improves Quality of Templated Quantum Well Emitters
Authors: Shapturenka Pavel , Pynn Christopher D. , Chan Lesley , Gordon Michael J. , DenBaars Steven P. 
Published: September 2023

Despite significant progress and multiple creative approaches taken toward the realization of long-wavelength III-nitride based light emitters over the past decade, high double-digit external quantum efficiencies remain elusive for GaN/InGaN based devices for wavelengths longer than 525 nm. This stems from the large mismatch between the GaN and InGaN lattice that manifests in deleterious crystal strain gradients, degrades surface growth morphology, and introduces diverse and potent nonradiative defects.
A promising route to mitigation of strain-based effects is templating epitaxial growth on relaxed InGaN epilayers; in particular, a known and controllable platform for uniaxial strain relaxation is the creation of 1-D misfit dislocation arrays at semipolar GaN/InGaN heterointerfaces. Leveraging work by Hardy et al. on achieving >200 nm thick, partially relaxed semipolar InGaN layers [1] and precise determination of InGaN epilayer strain state and composition by Young et al. [2], we explore the potential for 2-D buffer layer relaxation in (11-22) InGaN layers via micron- and sub-micron patterning. Cathodoluminescence microscopy and x-ray diffraction indicated significant increases in biaxial epilayer relaxation with increased pillar aspect ratio; quantum wells deposited atop these relaxed InGaN buffers showed dramatic threading dislocation reduction, luminescence and morphology improvements, and evidence of improved indium incorporation relative to planar samples at nominally identical growth conditions.
[1] Hardy, M.T., Young, E.C., Hsu, P.S., Haeger, D.A., Koslow, I.L., Nakamura, S., DenBaars, S.P., Speck, J.S. Suppression of m-plane and c-plane slip through Si and Mg doping in partially relaxed (20-21) InGaN/GaN heterostructures. Appl. Phys. Lett.
101, 132102 (2012).
[2] Young, E. C., Romanov, A.E., Speck, J.S., Determination of composition and lattice relaxation in semipolar ternary (In,Al,Ga)N strained layers from symmetric x-ray diffraction measurements. Appl. Phys. Express. 4, 061001 (2011).
A Capacitor-Based Synaptic Device with IGZO Access Transistors for Neuromorphic Computing
Authors: Won Jongun , Roh Youngchae , Kang Minseung , Park Yeaji , Kang Jaehyeon , Seo Hyeongjun , Joe Changhoon , Kim SangBum 
Published: September 2023

IGZO TFT has extremely low leakage current characteristics compared to Si-CMOS, so it can be applied not only to displays but also to various research fields. One of the important applications using IGZO TFT is analog-based synaptic device for the efficient implementation for deep learning. The application of IGZO TFT to a synaptic device was more widely studied after a synaptic device based on Si-CMOS and capacitor was devised in 2017(1). Since insufficient retention time was a remaining problem in Si-CMOS and capacitor-based storage synaptic devices, the combination of IGZO TFT with low leakage current and capacitor was a very attractive solution. However, because the viable p-type metal oxide TFT does not exist, linearity and symmetry of weight update, a major requirement of on-chip trainable synaptic devices, has been difficult to achieve. In our research, for the first time, we obtained linear and symmetric weight update characteristics by combining an IGZO TFT and a capacitor.
In addition, we verified the leakage characteristics of IGZO TFT and the retention characteristics of synaptic devices, which are the most important characteristics. Through the single TFT measurement result, we were able to obtain a leakage current per channel width 1µm of 10-17A, which is much smaller than the Si transistor. Lower leakage current will lead to better retention characteristics than conventional Si-CMOS-based devices, which will result in higher accuracy in deep neural network training. Based on the published results, the IGZO TFT synapse is projected to be able to achieve the retention time of ~4×109s using only 10fF capcacitor.
Another important factor that affects deep neural network training is cell-to-cell and device-to-device variation. As opposed to capacitive synaptic devices, resistive synaptic devices such as Resistive RAM and Phase Change Memory suffer from large device variation. We also verified the device variation characteristics, which are advantages of charge storage devices based on transistors and capacitors. The variation characteristics of the device were evaluated through the ΔG+3σ/ΔG-3σ(%) formula and an excellent result of ~200% was obtained.
In our research, we verified the main characteristics for on-chip training of synaptic devices based on IGZO TFT and capacitor: linearity and symmetry of weight update, retention characteristics and variation characteristics. The remarkable characteristics of synaptic devices based on IGZO TFT and capacitor will be a good candidate for on-chip training.
1. S. Kim, T. Gokmen, H. M. Lee, and W. E. Haensch, Midwest Symp. Circuits Syst., 2017-Augus, 422–425 (2017).
Acknowledgements
This research was supported by National R&D Program through the National Research Foundation of Korea(NRF) funded by Ministry of Science and ICT(NRF-2020M3F3A2A01081240)
(Invited) novel Functional π-Conjugated Materials for Photonics, Electronics, and Sensing
Authors: Sonar Prashant Murlidhar 
Published: September 2023

Next generation active electronic materials used in devices are undergoing continual improvements to generate devices that are high performance, lighter, flexible, stretchable, and more energy efficient with lower cost. Carbon based novel solution processable π-functional conjugated materials are the focus of intense academic and industrial research since they are important class of soft materials for large area electronics including transistors, displays, sensors and light harvesting devices. The active organic semiconducting materials are emerging due to their tunable light absorption/emission, interesting charge transport properties, relatively adequate HOMO-LUMO energies and ink formulation capability.
In my talk, I will explain the various classes of conjugated carbon-based materials either as polymers, small molecules or quantum dots prepared via chemically and electrochemically using various novel aromatic conjugated building blocks. In this presentation, the design, synthesis, optoelectronic properties, and device performance of novel advanced materials for field effect/electrochemical transistors, perovskite solar cells, light emitting diodes, optical sensors and various sensing devices will be discussed. Such materials and devices have great potential in future electronics, energy, health, and environmental monitoring.

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(Invited) Intelligent Fiber Electronics for Textile Computation
Authors: Yan Wei 
Published: September 2023

Textiles are an indispensable part of our everyday life. They provide us with protection, offer privacy, and form an intimate expression of ourselves through their aesthetics. Imparting functionality at the fiber level represents an intriguing path toward innovative textiles with a hitherto unparalleled functionality and value. The integration of a variety of electronic and optoelectronic materials within thermally-drawn fibers has enabled fiber electronics. A new generation of textiles that can see, hear and speak, sense, communicate, harvest and store energy, as well as store and process data is thus emerging, setting a stage for textiles to be the next frontier in computation. This talk will feature fiber electronics enabled intelligent textiles which is becoming a sophisticated platform delivering value-added services for our society.
Figure 1. Thermally drawn fibers that integrate chips, circuits, semiconductors, metals, dielectrics, composites, etc. can be directly woven into fabrics enabling a multitude of functionalities [1, 2].
[1] Wei Yan, Grace Noel, Gabriel Loke, Elizabeth Meiklejohn, Tural Khudiyev, Juliette Marion, Guanchun Rui, Jinuan Lin, Juliana Cherston, Atharva Sahasrabudhe, Joao Wilbert, Irmandy Wicaksono, Reed W. Hoyt, Anais Missakian, Lei Zhu, Chu Ma, John Joannopoulos, Yoel Fink*. Single fiber enables acoustic fabrics via nanometer scale vibrations. Nature 603 (2022) 616.
[2] Shengtai Qian, Mingyang Liu, Yuhai Dou, Yoel Fink and Wei Yan*. A ‘Moore’s law’ for fibers enables intelligent fabrics. National Science Review (2022)

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Aptamer-Based Electric-Double -Layer (EDL) Extended-Gated FET Biosensor for Detection of Cadmium Ion
Authors: Kuo TzuHan Han , Wang Yu-Lin Lin , Lin Chia Kai , Paulose Akhil K 
Published: September 2023

Cadmium ion (Cd2+) is a highly toxic heavy metal pollutant. It causes irreversible damage to human health even at low doses due to a long biological half-life and strong bioaccumulation. Common heavy metal detection includes Inductively Coupled Plasma with Atomic Emission, Spectroscopy (ICP-AES), Inductively coupled plasma mass spectrometry (ICP-MS), Flame Atomic Absorption Spectrophotometry (FAAS), and Graphite Furnace Atomic Absorption Spectrometry (GFAAS), and. However, these technologies are high-cost, time-consuming, complicated operations, and can't be detected immediately and accurately.
In this study, we developed an electric double-layer (EDL) extended-gate field effect transistor sensor based on aptamers to detect cadmium ions (Cd2+). Use N-channel enhanced-mode MOSFETs to connect the extended-gate array chips with aptamer modified. The aptamers were self-assembled on the gold electrode surface through Au-S bonds. Since the aptamer has a specific binding ability to cadmium ions, it will bind to the aptamer to form a stem-loop structure. The gate voltage changes caused by the structure change and then amplify the electrical signal through the transconductance of the field effect transistor. The linear detection range of this sensor for cadmium ions is from 1nM to 10uM. The Cd2+ calibration curve is shown a high correlation coefficient (R2 = 0.99001) and an excellent detection limit as low as 99.5 nＭ. Importantly, it responds to Cd2+ within 10 seconds. The sensor exhibits high selectivity in the presence of other heavy metals such as arsenic, chromium, lead, and mercury for electrical signal measurements. It also can be reused without significant signal attenuation.
The advantages of this method are convenient portability, short detection time, high sensitivity, and simple operation. It has a good prospect for detection in the daily life of cadmium environmental pollution.

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Development of Molecularly Imprinted Polymer Nanoparticles with High Affinity and Its Application to Electrochemical Biosensors
Authors: Man Youyuan , Nishitani Shoichi , Sakata Toshiya 
Published: September 2023

Molecularly imprinted polymers (MIPs) have the potentials to be low-cost and stable alternatives to natural receptors such as enzymes and antibodies for biosensors. In our group, we have been developing enzyme-/antibody-free electrochemical biosensors with the MIP-coated electrodes [1,2]. However, the conventional polymerization methods for MIPs have the limitations such as their heterogeneities that reduce high binding affinity sites and the presence of residual templated molecules, which are detrimental to biomolecular recognition. To address these issues, we have synthesized molecularly imprinted polymer nanoparticles (nano-MIPs) with virtually free of heterogeneous templates and higher affinity for target biomolecules by using a solid-phase approach synthesis method [3]. In this study, we have focused on the biomarkers such as human serum albumin (HSA) and glycated albumin (GA) for diabetes and then synthesized the redox-labeled HSA-templated nano-MIPs (HNMs) and GA-templated nano-MIPs (GNMs) for the electrochemical biosensor (Figure 1). The fundamental characteristics of HNMs and GNMs such as chemical composition, particle size, and binding affinity have been evaluated by using proton nuclear magnetic resonance (1H NMR), dynamic light scattering (DLS), atomic force microscopy (AFM), cyclic voltammetry (CV), isothermal titration calorimetry (ITC), and surface plasmon resonance (SPR).
References

Kajisa, T.; Sakata, T. ACS Appl. Mater. Interfaces 2018,10, 34983–34990.

Sakata, T.; Nishitani, S.; Kajisa, T. RSC Advances 2020, 10, 16999–17013.

Canfarotta, F. et al. Nat. Protoc. 2016, 3, 443-455.

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Monitoring the Effects Brought By a Drug on Myocardial Cells Using Field Effect Transistor (FET) Based Sensing Platform
Authors: Tsai Shu-Yi , Paulose Akhil K , Kalaimani Vishal Mani , Lin Chia Kai , Wang Yu-Lin 
Published: September 2023

Abstract: Ion channels are the membrane proteins that modulate the active flow of ions between cellular environment. These therapeutic targets are expressed in every active cell and can be used as important targets for cellular changes. The ion channels play an important role in different physiological processes including blood regulation, cell proliferation, nerve relaxation, etc. Various cardiac and neurological diseases have been reported to be related to ion channel regulation. They are brought through by the ion channel mutations. Several techniques are currently deployed for monitoring drug effectiveness of ion channels. Among these techniques, patch clamp technology is considered as a golden standard for monitoring the ion channel function. Unfortunately, the conventional patch clamp technologies are not enough to be employed in the early stages of drug discovery. Similarly, serval fluorescence detection methods and combination technologies have been developed for calcium ion channel detection. These assays are not suitable for large scale detection due to less selectivity and sensitivity.
At present, field-effect transistor-based biosensors (BioFETs) have been widely employed in various applications due to their non-invasive detection, and high sensitivity. In this work, we adopted an extended gated EDL-FET platform for rapid drug screening on myocardial cell lines (H9c2). The drug effectiveness was studied by tested nifedipine on myocardial cells which were mounted over an EDL-FET platform. Two different surface conditions were studied using Ca2+ treatment and the capability the of EDL-FET sensor as a drug screening platform was discussed.
Surface functionalization and Measurements

An extended gate chip was used as the sensor array. Before probe immobilization, the sensor electrode was treated with oxygen plasma. Cell attachment over the sensor platform was facilitated using a glycoprotein- Fibronectin. Traut’s reagent was used to modify fibronectin to initiate the covalent attachment to the sensor surface. Optical images and electrical readings were taken to ensure proper functionalization of the fibronectin-attached surface before the cells were seeded over it. Myocardial cells (H9c2 cells), removed from their culture media, were incubated over the functionalized electrodes for ~2 hours following which, electrical measurements were taken to establish a baseline reading using the BioFET device. Different concentrations of nifedipine [0 to 50 μM] and calcium ions [18 μM to 1.8 mM] were used to make testing solutions, which were used for monitoring various changes occurring on the ion channels of the myocardial cells.

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The Combination of Upconversion Nanoparticles and Photodynamic Therapy for Alzheimer’s Disease Treatment in Real-Time Monitoring
Authors: Lin Yu Chien , Wang Yu-Rong , Huang Tai-Ling , Chen Jung-Chih 
Published: September 2023

Alzheimer’s Disease (AD) consumes many medical resources in disease caring and delays symptoms. The aggregation of amyloid-beta (Aβ) is regarded as one of the foci of AD. It will form oligomers and polymerize into fibrotic neurofibrillary tangles leading to AD. Many research has focused on the diagnosis and risk factors of Aβ aggregation, trying to reverse the situation of Aβ aggregation by various approaches. However, there are no advantageous solutions that have been developed so far. Establishing a system from monitoring to controlling Aβ aggregation is urgently needed as a new approach for AD treatment. Once Aβ aggregation can be monitored and controlled to oxide and degrade it before forming oligomers. It will bring huge benefits to AD treatment. Therefore, this study combines photodynamic therapy (PDT) and quartz crystal micro-scale (QCM) techniques to realize the degradation of Aβ and monitor whether Aβ is degraded, and establish a complete system.
PDT has been applied in the medical field, especially for cancer treatment which induced oxidative stress results in different levels of protein oxidation. However, the limited excitation source limits the application of PDT, for example, the insufficient penetration depth of the excitation source prevents in vivo treatment of AD. Therefore, it needs to be combined with other materials to achieve in-depth treatment. This study proposes to modify photosensitizers on upconverting nanoparticles (UCNPs), and use 980 nm near-infrared to excite and then emit visible light to perform PDT. The combination of PDT and UCNPs generates the reactive oxygen species (ROS) to oxide Aβ and further degrade Aβ aggregation. However, most of the lanthanide metals and photosensitizers doped UCNPs are cytotoxic. Thus, Rose Bengal (RB) was selected as the reactive photosensitizer in this system owing to it being a metal-free, non-toxic, and widely available material. Also, it has been confirmed through research that RB can effectively transfer energy to form 1O2. To further ensure that material can be used in AD treatment, modify the SiO2 shell on the surface of UCNP to improve biocompatibility. The experimental results show that the cell survival rate can be maintained at about 80% when the concentration of UCNP reaches 25mg/mL.
The degradation of the Aβ peptide can be monitored using the QCM technique. QCM was applied for monitoring the differences in the oscillation frequency by the degradation of the Aβ peptide attached to UCNPs. Meanwhile, the DCFH-DA ROS assay kit was applied to estimate the Aβ peptide oxidation level. The results of this study show that the combination of UCNPs for PDT can effectively oxidize and degrade Aβ, and utilizing QCM and ROS assay kit can monitor the level of Aβ oxidation and degradation in real-time. The establishment of this system can help more potential AD patients, providing a diagnostic and treatment method.

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(Invited) hand-Held Florescence Microscope for Single Micro/Nano Particle Imaging
Authors: Sami Muhammad , Hassan Umer 
Published: September 2023

Fluorescence microscopes are commonly used to detect micro and nano biological entities (blood cells, microbes, functionalized particles etc.). Several experimental assays have been developed for biomarker measurements using this microscopy instrument. Common examples include cell viability analysis, surface receptor based specific blood cell enumeration, phagocytosis determination etc. However, the laboratory-based bench top fluorescence microscope suffers from high capital cost, maintenance, experienced staff for its operation and lack of portability. To address several of these challenges, here we have developed a hand-held, portable, 3D printed fluorescence microscope to enable single cell enumeration and nanoparticle imaging operated by smartphone.
3D printed platform is composed of top and bottom portions. The bottom portion includes excitation optics including an LED and excitation filter. While the top portion houses an emission filter, and a lens, while a smartphone can be placed on top portion for imaging. The excitation and emission filters can be swapped out for different fluorophores used. We have used the platform for imaging leukocytes collected from the whole blood. Blood samples were procured from Robert Wood Johnson Medical Hospital. We ran the leukocytes on our photonics platform and laboratory florescence microscope concurrently for a comparative analysis and found a high correlation of R2 = 0.99 in between cell counting results. Further, swapping different lenses can achieve high resolution for the imaging system. The resolution was verified by US Airforce Resolution Chart. This allowed us to image fluorescent nanoparticles up to 800nm at various concentrations and excitation modalities.
This platform can be used for single-cell analysis, specific leukocytes enumeration and nanoparticles imaging. The demonstrated results can enable significant applications to develop many biomedical and diagnostic assays.
Performance and Stability of Molten Carbonate Fuel Cell Cathode Electrode Under Carbon Capture Endurance Tests
Authors: Hilmi Abdelkader , Geary Timothy , Franco Adam , Yuh Chao-Yi , Willman Carl 
Published: September 2023

Introduction

The molten carbonate fuel cell (MCFC) has emerged as one of the promising alternatives for carbon capture from industrial and power generation CO2 sources. MCFC technology is less energy-intensive compared to conventional amine scrubbing that requires a significant amount of energy (steam) for solvent regeneration process.
MCFC has been commercially used for distributed power generation, however its use in carbon capture applications has been limited to development activities and a few demonstrations during the past decades. The electrochemical reactions taking place during cell operation involve the CO2 transfer from cathode to anode in the form of carbonate ions resulting in a gas stream with high CO2 concentration on the anode exhaust. Therefore, MCFC stack systems can be combined with conventional combustion-powered generators (coal and/or natural gas-based power plants) for simultaneous CO2 separation, power and hydrogen generation.
CO2 capture applications will typically take in flue gas from industrial furnaces, coal and gas fired combined cycle plants as the cathode inlet gas stream having low CO2 concentrations ranging from 4% to 10% by volume and high CO2 utilization (>90%). These CO2-lean conditions may pose a challenge for attaining good mass-transfer performance and life stability, therefore innovative approaches are needed in terms of hardware design and cathode structure to achieve long-term stability.
FCE has tested numerous single cells (250 cm2) and technology stacks (30 kW) under carbon capture operating conditions (4-8% CO2 in the cathode inlet as opposed to >12% in baseline MCFC systems) to understand impact of design parameters on performance, life, and to investigate design solutions for further enhancement. Figure 1 highlights the effect of cathode water content on CO2 utilization. It appears that differences exist between the ideal and measured CO2 utilizations, indicating that less CO2 is transferring from the cathode to anode than expected. This CO2 transference reduction becomes more pronounced with higher water concentration, suggesting that a species other than CO3
2- ion, likely hydroxide (OH- ion), may be generated and transported through the electrolyte matrix.
This paper will review the cathode material stability and electrochemical performance under long-term carbon-capture operation. The effect of parameters such as water content, gas composition, utilization, and electrolyte chemistry, as well as approaches to enhance the CO2 capture efficiency and life, will be discussed.

Figure 1