Advection Flows‐Enhanced Magnetic Separation for High‐Throughput Bacteria Separation from Undiluted Whole Blood

A major challenge to scale up a microfluidic magnetic separator for extracorporeal blood cleansing applications is to overcome low magnetic drag velocity caused by viscous blood components interfering with magnetophoresis. Therefore, there is an unmet need to develop an effective method to position magnetic particles to the area of augmented magnetic flux density gradients while retaining clinically applicable throughput. Here, a magnetophoretic cell separation device, integrated with slanted ridge‐arrays in a microfluidic channel, is reported. The slanted ridges patterned in the microfluidic channels generate spiral flows along the microfluidic channel. The cells bound with magnetic particles follow trajectories of the spiral streamlines and are repeatedly transferred in a transverse direction toward the area adjacent to a ferromagnetic nickel structure, where they are exposed to a highly augmented magnetic force of 7.68 µN that is much greater than the force (0.35 pN) at the side of the channel furthest from the nickel structure. With this approach, 91.68% ± 2.18% of Escherichia coli (E. coli) bound with magnetic nanoparticles are successfully separated from undiluted whole blood at a flow rate of 0.6 mL h^?1 in a single microfluidic channel, whereas only 23.98% ± 6.59% of E. coli are depleted in the conventional microfluidic device.     

Fabrication of Intermetallic Compounds by Spark Plasma Sintering

The characteristics of spark plasma sintering, a new method of powder processing, were investigated. Four systems of intermetallic compounds—Ti-Al, Ti-Al-Cr, Mo-Si, and Mo-Si-Nb—were fabricated, and the formation process of compounds, the formed phases, and the microstructure of samples were observed. During the sintering of all the compositions of mixed powders, most of the compounds were formed by combustion reaction which occurred at almost the same temperature as the conventional combustion reaction temperature. The fabricated samples were well densified, however, the relative densities of the Mo-Si samples were lower than the Ti-Al samples. Ultrasonic images show that no internal defects were found in any sample and the grain size became finer with the increase in the Cr content in the Ti-Al system and Nb content in the Mo-Si system. The formed phases of Ti:Al=1:1 composition samples were TiAl and Ti₃Al phases, and Ti-Al added Cr samples consisted of TiAl, Ti₃Al, Cr₂Al, and Cr₉Al₁₇ phases. The sample synthesized with Mo:Si=1:2 mixed powders had only MoSi₂ phases, and Mo-Si samples with added Nb consisted of four phases: MoSi₂ with a small amount of Mo₅Si₃ phases in the matrix and Nb₅Si₃ with unreacted Nb for dispersed phases.     

An amorphous silicon triode rectifier switching device for active-matrix liquid-crystal display

A triode rectifier switching (TRS) device composed of two amorphous silicon (a-Si) diodes and one resistor has been demonstrated experimentally to be a good switching device for active-matrix liquid-crystal display (AMLCD). The output and transfer characteristics of a TRS are very similar to those of an a-Si thin-film transistor. High on/off current ratio (>5/spl times/10/sup 6/) and low off-state leakage currents (<0.4 pA) have been demonstrated with a-Si diodes and a-Si resistor, indicating that the TRS is suitable for high-performance switching devices for AMLCD.     

New Charge Carrier Transport-Assisting Paths in Ultra-Long GaN Microwire UV Photodetector

GaN-based materials are the hottest research topic in UV photodetectors (PDs) because of their low operating voltage, small volume, long lifetime, high-temperature resistance, and low energy consumption. However, there are still fundamental issues to be overcome, and the most important issue is to get a photoconductive gain. In this paper, the following new approaches are provided to innovatively improve the photoconductive gain of UV PDs in GaN-based materials. First, the aspect ratio of the 1D GaN microwire (MW) structure is dramatically improved by analyzing the pulse growth mechanism using the metal-organic vapor deposition system. Second, the comprehensive strain behavior in the MW epitaxial growth system is successfully analyzed. Third, the fabricated metal-semiconductor-metal-based MW UV PD shows photoresponsivity and sensitivity of 28.365 A W⁻¹ and 93.16%, respectively, at the −2 V bias, which significantly outperforms the conventional structures in the UV region. Finally, a trap-assisted Poole–Frenkel effect-based energy bandgap mechanism, that allows the defect level formed by lattice mismatch between the substrate and GaN to be used as an electron carrier path, is newly defined. This study will present the direction of future UV PDs by providing a new MW structure based on GaN materials, a third-generation semiconductor.     

Efficient and Scalable Large-Area Organic Solar Cells by Asymmetric Nonfullerene Acceptors Based on 9H-Indeno[1,2-b]pyrazine-2,3,8-Tricarbonitrile

It remains challenging to fabricate efficient, scalable large-area organic solar cells (OSCs) owing to the unfavorable morphology of photoactive blend films. To address this challenge, two asymmetric nonfullerene acceptors (NFAs) IPC1CN-BBO-IC2F and IPC1CN-BBO-IC2Cl are synthesized, where 12,13-bis(2-butyloctyl)-3,9-diundecyl-12,13-dihydro-[1,2,5]thiadiazolo[3,4-e]thieno[2′“,3′”:4′,5′]thieno[2′,3′:4,5]pyrrolo[3,2-g]thieno[2′,3′:4,5]thieno-[3,2-b]indole (BBO) is the molecular core, and two types of end groups are appended to its ends, namely the 9H-indeno[1,2-b]pyrazine-2,3,8-tricarbonitrile (IPC1CN) end group and one of 2-(5,6-dihalo-3-oxo-2,3-dihydro-1H-inden-1-ylidene)malononitrile end groups (IC2F or IC2Cl). These NFAs facilitate effective tuning of light absorption and energy levels, offer high carrier mobilities, and allow for the formation of appropriate morphologies. Note that these benefits apply even to large-area devices, unlike typical Y6-based NFAs. In addition, a random copolymer PM6-PBDBT(55) is synthesized and its energy levels are optimally matched with those of the asymmetric NFAs. The blade-coated 1 cm²-area OSCs based on PM6-PBDBT(55):IPC1CN-BBO-IC2Cl exhibit a PCE of 14.12%, which is higher than that of PM6-PBDBT(55)-IPC1CN-BBO-IC2F-based OSCs. More importantly, the PM6-PBDBT(55):IPC1CN-BBO-IC2Cl-based large-area (58.50 cm²) modules yield an impressive PCE of 11.28% with a small cell-to-module loss in fill factor. These results suggest that a combination of the asymmetric molecular design using the IPC1CN group and the terpolymer strategy will pave a new path for fabricating highly efficient and scalable large-area OSCs.     

Broadband omnidirectional light detection in flexible and hierarchical ZnO/Si heterojunction photodiodes

The development of flexible photodetectors has received great attention for future optoelectronic applications including flexible image sensors, biomedical imaging, and smart, wearable systems. Previously, omnidirectional photodetectors were only achievable by integration of a hemispherical microlens assembly on multiple photodetectors. Herein, a hierarchical photodiode design of ZnO nanowires (NWs) on honeycomb-structured Si (H-Si) membranes is demonstrated to exhibit excellent omnidirectional light-absorption ability and thus maintain high photocurrents over broad spectral ranges (365 to 1,100 nm) for wide incident angles (0° to 70°), which enabled broadband omnidirectional light detection in flexible photodetectors. Furthermore, the stress-relieving honeycomb pattern within the photodiode micromembranes provided photodetectors with excellent mechanical flexibility (10% decrease in photocurrent at a bending radius of 3 mm) and durability (minimal change in photocurrent over 10,000 bending cycles). When employed in semiconductor thin films, the hierarchical NW/honeycomb heterostructure design acts as an efficient platform for various optoelectronic devices requiring mechanical flexibility and broadband omnidirectional light detection.

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Development of an HL7 interface engine, based on tree structure and streaming algorithm, for large-size messages which include image data

A basic assumption of Health Level Seven (HL7) protocol is 'No limitation of message length'. However, most existing commercial HL7 interface engines do limit message length because they use the string array method, which is run in the main memory for the HL7 message parsing process. Specifically, messages with image and multi-media data create a long string array and thus cause the computer system to raise critical and fatal problem. Consequently, HL7 messages cannot handle the image and multi-media data necessary in modern medical records. This study aims to solve this problem with the 'streaming algorithm' method. This new method for HL7 message parsing applies the character-stream object which process character by character between the main memory and hard disk device with the consequence that the processing load on main memory could be alleviated. The main functions of this new engine are generating, parsing, validating, browsing, sending, and receiving HL7 messages. Also, the engine can parse and generate XML-formatted HL7 messages. This new HL7 engine successfully exchanged HL7 messages with 10 megabyte size images and discharge summary information between two university hospitals.     

The simulation design and analysis of a Flexible Manufacturing System with Automated Guided Vehicle System

This paper presents the simulation design and analysis of a Flexible Manufacturing System (FMS) with an Automated Guided Vehicle system (AGVs). To maximize the operating performance of FMS with AGVs, many parameters must be considered, including the number, velocity, and dispatching rule of AGV, part-types, scheduling, and buffer sizes. Of the various critical factors, we consider the following three: (1) minimizing the congestion; (2) minimizing the vehicle utilization; and (3) maximizing the throughput. In this paper, we consider the systematic analysis methods that combine a simulation-based analytic and optimization technique that is Multi-Objective Non-Linear Programming (MONLP) and Evolution Strategy (ES). MONLP determines the design parameters of the system through multi-factorial and regression analyses. ES is used to verify each parameter for simulation-based optimization. A validation test for the two methods is conducted. This method-based approach towards design yields the correct experimental results, ensures confidence in the specification of design parameters and supports a robust framework for analysis.     

First viscosity of dilute3He-4He mixtures below 0.6 K

Starting with the Boltzmann transport equation, the first viscosity of dilute³He-⁴He mixtures for various³He concentrations x is evaluated up to around T 0.6 K by including the contribution from three-phonon processes (3PP) in the anomalous elementary excitation spectrum of liquid⁴He. Due to 3PP, the characteristic time for³He viscosity at high temperatures, i.e., T2T_F where T_F is the³He Fermi temperature, is evaluated as 5 × 10^–12/xT, which is smaller than the value estimated by Rosenbaum et al. This is interpolated with in the degenerate (quantum) region, TT_F. The obtained viscosities are in better agreement with experimental results than those of Baym and Saam, whose theory does not include 3PP. However, at very low concentrations there exists a discrepancy between the present theory and experiments, so that an alternate treatment should be considered.