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81.
Tuberculosis (TB) is one of the deadliest diseases known to man and ranks among the top ten global causes of fatalities. Children often develop a paucibacillary form of this disease which makes diagnosis arduous even with the aid of sophisticated techniques. In these cases, the concentration of bacteria in their sputum falls below the lowest limit of detection for sputum smear microscopy, the technique predominantly used in developing countries. In this study we aim to test the hypothesis that modifying a polymer, often used in buccal swabs, could assist in creating a capturing and concentrating oral swab for Mycobacterium tuberculosis (Mtb), the pathogenic bacterial species responsible for TB. Such a device will assist in meeting the detection limit and allow for rapid detection of the disease. The polymer used was a micro fibrous form of poly(ethylene terephthalate) (PET) which was surface functionalized with Concanavalin A (Con A), a lectin based adhesin with an affinity for the mannose groups on the Mtb cell wall. The functionalization was mediated with glutaraldehyde as bioconjugate molecule and found to produce a surface uniformly covered with Con A. Affinity studies between the modified fibers and the Mycobacterium bovis bacillus Calmette-Guérin (BCG), as Mtb mimic, were conducted to evaluate the capturing abilities of the substrate. The results indicate that the fibers avidly captured BCG and that the fibrous matrix aided in its function. Dilution studies showed successful capturing of the bacterial species at concentrations characteristic of paucibacillary cases. In this study a commercial polymeric material was successfully surface modified with a biological entity to create a substrate to which Mtb could adhere and accordingly be captured.  相似文献   
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83.
ABSTRACT

The radical limit of post-anthropocentric creativity is a mode of completely nonhuman creative endeavour. Yet, the anthropocentrism prevails and conceptions of radically different civilisations and cultures are defined by current human thought that shapes and limits the understanding of what a genuinely alternative cultural production might entail. This article uses the Kardashev scale of civilisations, classified according to energy consumption at the planetary, stellar and galactic scales to consider culture beyond the current limits of an inherently anthropocentric perspective. In considering microdimensional, informational and universal extensions of Kardashev's scale, critical reflections on the anthropocentric limits of cultural epistemology create an opportunity to posit a universal framework of creativity.  相似文献   
84.
This paper presents an abstract specification of an enforcement mechanism of usage control for Grids, and verifies formally that such mechanism enforces UCON policies. Our technique is based on KAOS, a goal-oriented requirements engineering methodology with a formal LTL-based language and semantics. KAOS is used in a bottom-up form. We abstract the specification of the enforcement mechanism from current implementations of usage control for Grids. The result of this process is agent and operation models that describe the main components and operations of the enforcement mechanism. KAOS is used in top-down form by applying goal-refinement in order to refine UCON policies. The result of this process is a goal-refinement tree, which shows how a goal (policy) can be decomposed into sub-goals. Verification that a policy can be enforced is then equivalent to prove that a goal can be implemented by the enforcement mechanism represented by the agent and operation models.  相似文献   
85.
E-Mail-Verschlüsselung könnte längst flächendeckend Verwendung finden. Der Beitrag gibt eine Antwort auf die Frage, warum dies nicht der Fall ist–und macht Vorschläge, was getan werden sollte, um dies zu ändern.  相似文献   
86.
E-procurement and supplier-relationship management systems have helped to substantially advance process execution in supply management. However, current supply network systems still face challenges of high data integration efforts, as well as the decoupling of structured data and processes from the growing amount of digitalized unstructured interactions of supply management professionals. Inspired by the room for improvement posed by this challenges, our research proposes a design for a supply network artifact in supplier qualification that addresses these problems by enabling holistic integration of data, processes, and people. The artifact is developed following an action design research approach. Building on a set of meta-requirements derived from literature and practice explorations, we conceptualize two design principles and derive corresponding design decisions that have been implemented in an software artifact. Finally, we formulate testable hypotheses and evaluate the artifact and its design in the context of supplier qualification. Our results show that the proposed design reduces mental effort of supply management professionals and significantly increases efficiency when performing typical supply network tasks such as supplier qualification.  相似文献   
87.
Impacts of Internet use on political information seeking and subsequent processes have been subject to much debate. A 2‐session online field study presented online search results on political topics to examine selective exposure and its attitudinal impacts. Session 1 captured attitudes, including their accessibility. Session 2 tracked what online search results participants selected and how long they read them; participants then reported attitudes again. The study represented a 4x8x2x2 within‐subjects design: 4 topics, 8 browsing intervals each, with articles presenting opposing stances, with low versus high source credibility. Attitude‐consistent messages and messages from high‐credibility sources were preferred. Exposure to attitude‐consistent search results increased attitude accessibility and reinforced attitudes, whereas exposure to attitude‐discrepant content had opposite effects, regardless of messages' source credibility.  相似文献   
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89.
This paper presents a combination of novel feature vectors construction approach for face recognition using discrete wavelet transform (DWT) and field programmable gate array (FPGA)-based intellectual property (IP) core implementation of transform block in face recognition systems. Initially, four experiments have been conducted including the DWT feature selection and filter choice, features optimisation by coefficient selections and feature threshold. To examine the most suitable method of feature extraction, different wavelet quadrant and scales have been evaluated, and it is followed with an evaluation of different wavelet filter choices and their impact on recognition accuracy. In this study, an approach for face recognition based on coefficient selection for DWT is presented, and the significant of DWT coefficient threshold selection is also analysed. For the hardware implementation, two architectures for two-dimensional (2-D) Haar wavelet transform (HWT) IP core with transpose-based computation and dynamic partial reconfiguration (DPR) have been synthesised using VHDL and implemented on Xilinx Virtex-5 FPGAs. Experimental results and comparisons between different configurations using partial and non-partial reconfiguration processes and a detailed performance analysis of the area, power consumption and maximum frequency are also discussed in this paper.  相似文献   
90.
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