6,281 research outputs found

    A comparison between e-government practices in Taiwan and New Zealand.

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    Few studies have focused on comparing the state of e-government in Western- and Non-Western settings, where the political, social, economic, and cultural environments can be markedly different. This paper compares the views of local authority policymakers in Taiwan and New Zealand, in order to judge the sophistication of their e-government initiatives via the formal and informal policies underpinning website development. Good level of agreement were observed between the Taiwanese and New Zealander respondents for the high levels of significance they attached to 3 key issues, which the authors argue are critical for successful e-government: Accessibility, Security and Privacy. Similarly, the policymakers agreed on a medium level of significance for the 7 key issues: E-procurement, Digital Divide, Private Sector, Taxation, Cultural Obstacles, IT Workforce, and Social Effects (and on a low level of significance for E-Tailing). It was concluded that government policymakers in both countries, in an era of commercial online social networking, are continuing to favour pushing(what they deem to be important) information to citizens, rather than creating collaborative service channels with citizens, contractors and suppliers or integrating separate service processes to satisfy all stakeholders. An attendant lack of commitment to promoting heightened (e-)democracy was also noted, especially in New Zealand

    Probing the DNA kink structure induced by the hyperthermophilic chromosomal protein Sac7d

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    Sac7d, a small, abundant, sequence-general DNA-binding protein from the hyperthermophilic archaeon Sulfolobus acidocaldarius, causes a single-step sharp kink in DNA (∼60°) via the intercalation of both Val26 and Met29. These two amino acids were systematically changed in size to probe their effects on DNA kinking. Eight crystal structures of five Sac7d mutant–DNA complexes have been analyzed. The DNA-binding pattern of the V26A and M29A single mutants is similar to that of the wild-type, whereas the V26A/M29A protein binds DNA without side chain intercalation, resulting in a smaller overall bending (∼50°). The M29F mutant inserts the Phe29 side chain orthogonally to the C2pG3 step without stacking with base pairs, inducing a sharp kink (∼80°). In the V26F/M29F-GCGATCGC complex, Phe26 intercalates deeply into DNA bases by stacking with the G3 base, whereas Phe29 is stacked on the G15 deoxyribose, in a way similar to those used by the TATA box-binding proteins. All mutants have reduced DNA-stabilizing ability, as indicated by their lower T(m) values. The DNA kink patterns caused by different combinations of hydrophobic side chains may be relevant in understanding the manner by which other minor groove-binding proteins interact with DNA

    Prevalence of latent tuberculosis infection in BCG-vaccinated healthcare workers by using an interferon-gamma release assay and the tuberculin skin test in an intermediate tuberculosis burden country

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    BackgroundThe risk of healthcare workers (HCWs) acquiring tuberculosis (TB) infection is high. We determined the prevalence of latent TB infection (LTBI) in HCWs with a high Bacille Calmette-Guérin (BCG) vaccine coverage in an intermediate TB burden country by using an interferon-gamma release assay [QuantiFERON-TB Gold (QFT-G)] and by using the tuberculin skin test (TST). Risk factors associated with a positive test were determined.MethodsThis prospective cross-sectional study enrolled HCWs from a medical center in Taiwan. Participants were grouped into workers without exposure (Group 1) and workers who self-reported a history of TB exposure (Group 2). All participants completed a questionnaire to collect demographic information and risk factors for acquiring TB. The QFT-G test and the TST were administered and risk factors for a positive test were analyzed.ResultsWe recruited 193 HCWs [149 (77.2%) female workers] with a mean age of 35.6 years. All were BCG-vaccinated. The prevalence of LTBI was 88.8% (based on the TST) and 14.5% (based on the QFT-G test). There was no difference between HCWs with and without known exposure to TB. Agreement between the tests was poor (i.e., the kappa value was less than 0.05). Multivariable logistic regression showed that only the QFT-G test was associated with age (35 years or greater) (adjusted OR, 2.53; p = 0.03).ConclusionBy using the QFT-G test or TST, this study found a similar prevalence of LTBI in HCWs with and without known exposure to TB. This suggests that in intermediate TB burden countries exposure to TB may occur within the hospital and within the community. Compared to the TST, the QFT-G test was correlated better with age, which is a known risk factor for latent TB infection

    Adaptive-Compression Based Congestion Control Technique for Wireless Sensor Networks

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    Congestion in a wireless sensor network causes an increase in the amount of data loss and delays in data transmission. In this paper, we propose a new congestion control technique (ACT, Adaptive Compression-based congestion control Technique) based on an adaptive compression scheme for packet reduction in case of congestion. The compression techniques used in the ACT are Discrete Wavelet Transform (DWT), Adaptive Differential Pulse Code Modulation (ADPCM), and Run-Length Coding (RLC). The ACT first transforms the data from the time domain to the frequency domain, reduces the range of data by using ADPCM, and then reduces the number of packets with the help of RLC before transferring the data to the source node. It introduces the DWT for priority-based congestion control because the DWT classifies the data into four groups with different frequencies. The ACT assigns priorities to these data groups in an inverse proportion to the respective frequencies of the data groups and defines the quantization step size of ADPCM in an inverse proportion to the priorities. RLC generates a smaller number of packets for a data group with a low priority. In the relaying node, the ACT reduces the amount of packets by increasing the quantization step size of ADPCM in case of congestion. Moreover, in order to facilitate the back pressure, the queue is controlled adaptively according to the congestion state. We experimentally demonstrate that the ACT increases the network efficiency and guarantees fairness to sensor nodes, as compared with the existing methods. Moreover, it exhibits a very high ratio of the available data in the sink

    Defect characterization of InAs/InGaAs quantum dot p-i-n photodetector grown on GaAs-on-V-grooved-Si substrate

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    The performance of semiconductor devices on silicon can be severely degraded by the presence of dislocations incurred during heteroepitaxial growth. Here, the physics of the defect mechanisms, characterization of epitaxial structures, and device properties of waveguide photodetectors (PDs) epitaxially grown on (001) Si are presented. A special GaAs-on-V-grooved-Si template was prepared by combining the aspect ratio trapping effects, superlattice cyclic, and strain-balancing layer stacks. A high quality of buffer structure was characterized by atomic force microscopy (AFM) and electron channeling contrast imaging (ECCI) results. An ultralow dark current density of 3.5 × 10–7A/cm2 at 300 K was measured under −1 V. That is 40× smaller than the best reported value of epitaxially grown InAs/GaAs quantum dot photodetector structure on GaP/Si substrate. Low frequency noise spectroscopy was used to characterize the generation and recombination related deep levels. A trap with an activation energy of 0.4 eV was identified, which is near the middle bandgap. With low frequency noise spectroscopy along with the current–voltage and capacitance–voltage characterizations, the recombination lifetime of 27 μs and trap density of 5.4 × 1012 cm–3 were estimated

    A machine vision based automatic optical inspection system for measuring drilling quality of printed circuit boards

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    In this paper, we develop and put into practice an automatic optical inspection (AOI) system based on machine vision to check the holes on a printed circuit board (PCB). We incorporate the hardware and software. For the hardware part, we combine a PC, the three-axis positioning system, a lighting device, and charge-coupled device cameras. For the software part, we utilize image registration, image segmentation, drill numbering, drill contrast, and defect displays to achieve this system. Results indicated that an accuracy of 5 mu m could be achieved in errors of the PCB holes allowing comparisons to be made. This is significant in inspecting the missing, the multi-hole, and the incorrect location of the holes. However, previous work only focuses on one or other feature of the holes. Our research is able to assess multiple features: missing holes, incorrectly located holes, and excessive holes. Equally, our results could be displayed as a bar chart and target plot. This has not been achieved before. These displays help users to analyze the causes of errors and immediately correct the problems. In addition, this AOI system is valuable for checking a large number of holes and finding out the defective ones on a PCB. Meanwhile, we apply a 0.1-mm image resolution, which is better than others used in industry. We set a detecting standard based on 2-mm diameter of circles to diagnose the quality of the holes within 10 s

    Color-tunable mixed photoluminescence emission from Alq3 organic layer in metal-Alq3-metal surface plasmon structure

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    This work reports the color-tunable mixed photoluminescence (PL) emission from an Alq(3) organic layer in an Au-Alq(3)-Au plasmonic structure through the combination of organic fluorescence emission and another form of emission that is enabled by the surface plasmons in the plasmonic structure. The emission wavelength of the latter depends on the Alq(3) thickness and can be tuned within the Alq(3) fluorescent spectra. Therefore, a two-color broadband, color-tunable mixed PL structure was obtained. Obvious changes in the Commission Internationale d’Eclairage (CIE) coordinates and the corresponding emission colors of Au-Alq(3)-Au samples clearly varied with the Alq(3) thickness (90, 130, and 156 nm)

    Traumatic Neuroma around the Celiac Trunk after Gastrectomy Mimicking a Nodal Metastasis: A Case Report

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    Traumatic neuroma is a well-known disorder that occurs after trauma or surgery involving the peripheral nerve and develops from a nonneoplastic proliferation of the proximal end of a severed, partially transected, or injured nerve. We present a case of traumatic neuroma around the celiac trunk after gastrectomy in a 56-year-old man, which was confirmed by pathology. CT demonstrated the presence of a lobulated, homogeneous, hypoattenuating mass around the celiac trunk, mimicking a nodal metastasis
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