Using a microfluidic device for 1 μl DNA microarray hybridization in 500 s

This work describes a novel and simple modification of the current microarray format. It reduces the sample/reagent volume to 1 μl and the hybridization time to 500 s. Both 20mer and 80mer oligonucleotide probes and singly labeled 20mer and 80mer targets, representative of the T-cell acute lymphocytic leukemia 1 (TAL1) gene, have been used to elucidate the performance of this hybridization approach. In this format, called shuttle hybridization, a conventional flat glass DNA microarray is integrated with a PMMA microfluidic chip to reduce the sample and reagent consumption to 1/100 of that associated with the conventional format. A serpentine microtrench is designed and fabricated on a PMMA chip using a widely available CO(2) laser scriber. The trench spacing is compatible with the inter-spot distance in standard microarrays. The microtrench chip and microarray chip are easily aligned and assembled manually so that the microarray is integrated with a microfluidic channel. Discrete sample plugs are employed in the microchannel for hybridization. Flowing through the microchannel with alternating depths and widths scrambles continuous sample plug into discrete short plugs. These plugs are shuttled back and forth along the channel, sweeping over microarray probes while re-circulation mixing occurs inside the plugs. Integrating the microarrays into the microfluidic channel reduces the DNA–DNA hybridization time from 18 h to 500 s. Additionally, the enhancement of DNA hybridization reaction by the microfluidic device is investigated by determining the coefficient of variation (CV), the growth rate of the hybridization signal and the ability to discriminate single-base mismatch. Detection limit of 19 amol was obtained for shuttle hybridization. A 1 μl target was used to hybridize with an array that can hold 5000 probes

Reliability of flexible low temperature poly-silicon thin film transistor

This work reports the effect of mechanical stress-induced degradation in flexible low-temperature polycrystalline-silicon thin-film transistors. After 100,000 iterations of channel-width-direction mechanical compression at R=2mm, a significant shift of extracted threshold voltage and an abnormal hump at the subthreshold region were found. Simulation reveals that both the strongest mechanical stress and electrical field takes place at both sides of the channel edge, between the polycrystalline silicon and gate insulator. The gate insulator suffered from a serious mechanical stress and result in a defect generation in the gate insulator. The degradation of the threshold voltage shift and the abnormal hump can be ascribed to the electron trapping in these defects. In addition, this work introduced three methods to reduce the degradation cause by the mechanical stress, including the quality improvement of the gate insulator, organic trench structure and active layer with a wing structure. Please click Additional Files below to see the full abstract

Transforaminal Endoscopic Lumbar Discectomy with Foraminoplasty for Down-migrated Disc Herniation: A Single-center Observational Study

Objective Full-endoscopic lumbar discectomy has evolved to be an alternative for the treatment of lumbar disc herniation. Regarding the techniques, the transforaminal approach remains the primary access. The indications of transforaminal endoscopic lumbar discectomy (TELD) have expanded following the evolution of the techniques, especially TELD with foraminoplasty. This study is to evaluate the efficacy of the TELD with foraminoplasty for downward migrated lumbar disc herniation. Methods The authors conducted a retrospective study with prospectively collected data in a single center. The study enrolled patients with downward migrated lumbar disc herniation undergoing TELD with foraminoplasty from May 2009 to June 2018. All procedures were performed under local anesthesia. Patients' demographics, clinical outcomes, and satisfaction with surgery were recorded. Results There were 126 patients included in the current study. The mean age was 50.7±17.4 years old. The leg pain and functional outcome scores significantly improved after the operation. There was no neurological deficit or iatrogenic instability requiring fusion surgery. The operation time was within 2 hours in most cases (92%). Thirteen patients reported minor complications, but symptoms were self-limited or responded to conservative treatment. The operation satisfied 94.4% of patients. Seven cases underwent revision surgery within six months due to recurrence. Conclusion TELD with foraminoplasty under local anesthesia can be an alternative for downward migrated lumbar disc herniation. Nerve root irritation can be detected without intraoperative neurophysiological monitoring when the patient is awake during the procedures. The clinical outcomes were favorable and the risk of complication was low with the current technique

Near-infrared H2 and continuum survey of extended green objects. II. Complete census for the northern Galactic plane

We discuss 94 Extended Green Objects (EGOs) in the northern Galactic plane cataloged by Cyganowski et al., based on near-infrared narrow H2 (2.122 μm) and continuum observations from the United Kingdom Infrared Telescope. This data set is three times larger than the one in our previous study and is unbiased by preselection. As discussed in the previous paper, the morphologies of the 4.5 μm emission generally resemble those of the near-infrared continuum, but are different from those of the H2 emission. Of our sample, only 28% of EGOs with H2 emission show similar morphologies between 4.5 μm and H2 emission. These results suggest that the 4.5 μm emission mainly comes from scattered continuum from the embedded young stellar objects, and partially from H2 emission. About half of EGOs are associated with H2 outflows, if the H 2 outflow incompleteness is considered. The H2 outflow detection rate for EGOs with K-band detections (61%) is significantly higher than for those without K-band detections (36%). This difference may be due to the fact that both H2 and K-band emissions are associated with outflows, i.e., H2 emission and K-band continuum are associated with shocks and outflow cavities, respectively. We also compared the correlation between the H2 outflows and Class I 44 GHz methanol masers from the literature. The methanol masers can be located upstream or downstream of the H2 outflows and some bright H2 spots or outflows are not associated with methanol masers, suggesting that methanol masers and H 2 emission trace different excitation conditions. © 2013. The American Astronomical Society. All rights reserved.

Low Cost Seismic Network Practical Applications for Producing Quick Shaking Maps in Taiwan

Two major earthquakes of ML greater than 6.0 occurred in Taiwan in the first half of 2013. The vibrant shaking brought landslides, falling rocks and casualties. This paper presents a seismic network developed by National Taiwan University (NTU) with 401 Micro-Electro Mechanical System (MEMS) accelerators. The network recorded high quality strong motion signals from the two events and produced delicate shaking maps within one minute after the earthquake occurrence. The high shaking regions of the intensity map produced by the NTU system suggest damage and casualty locations. Equipped with a dense array of MEMS accelerometers, the NTU system is able to accommodate 10% signals loss from part of the seismic stations and maintain its normal functions for producing shaking maps. The system also has the potential to identify the rupture direction which is one of the key indices used to estimate possible damage. The low cost MEMS accelerator array shows its potential in real-time earthquake shaking map generation and damage avoidance

Performance measurement systems, TQM, and multi-level firm performance: a person-organisation fit perspective

For firms implementing TQM, there is a need to redesign performance measurement systems (PMS). Innovated PMS ought to have measurement diversity in their structure with considering the spirit of TQM and emphasize the congruence of goals between employees and firms by adding the viewpoint of person-organisation fit (P-O fit). This paper adopts structural equation modeling (SEM) to examine Taiwanese manufacturing firms to study the association between the P-O fit of PMS and the implementation of TQM, as well as the effects of the adaptation of both to firm performance. Particularly, this paper examines firm performance at multiple levels and gathers data from multiple sources, including archival files and self-reported data from surveys

Acute necrotizing eosinophilic myocarditis in a young woman

Abstract Eosinophilic myocarditis is recognized by severe heart failure and marked eosinophilia infiltration resulting from different etiologies. Acute necrotizing eosinophilic myocarditis, the initial presentation of the disease, is rare and often fatal, with unique echocardiographic pictures, and followed by endocardial thrombosis and chronic endomyocardial fibrosis. We report a young female with acute lymphoblastic leukemia who presented fever and acute heart failure syndrome. The echocardiography showed severe left ventricle diastolic dysfunction with preserved ejection fraction. Systemic eosinophilia and the unique echocardiographic images made the diagnosis of acute necrotizing eosinophilic myocarditis. The patient survived after intensive cytotoxic chemotherapy including high-dose steroid