135 research outputs found

    Radio Frequency Identification Technology: Applications, Technical Challenges and Strategies

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    Purpose - The purpose of this paper is to discuss the technology behind RFID systems, identify the applications of RFID in various industries, and discuss the technical challenges of RFID implementation and the corresponding strategies to overcome those challenges. Design/methodology/approach - Comprehensive literature review and integration of the findings from literature. Findings - Technical challenges of RFID implementation include tag cost, standards, tag and reader selection, data management, systems integration and security. The corresponding solution is suggested for each challenge. Research limitations/implications - A survey type research is needed to validate the results. Practical implications - This research offers useful technical guidance for companies which plan to implement RFID and we expect it to provide the motivation for much future research in this area. Originality/value - As the infancy of RFID applications, few researches have existed to address the technical issues of RFID implementation. Our research filled this gap

    Refinement of the Retinogeniculate Synapse by Bouton Clustering

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    SummaryMammalian sensory circuits become refined over development in an activity-dependent manner. Retinal ganglion cell (RGC) axons from each eye first map to their target in the geniculate and then segregate into eye-specific layers by the removal and addition of axon branches. Once segregation is complete, robust functional remodeling continues as the number of afferent inputs to each geniculate neuron decreases from many to a few. It is widely assumed that large-scale axon retraction underlies this later phase of circuit refinement. On the contrary, RGC axons remain stable during functional pruning. Instead, presynaptic boutons grow in size and cluster during this process. Moreover, they exhibit dynamic spatial reorganization in response to sensory experience. Surprisingly, axon complexity decreases only after the completion of the thalamic critical period. Therefore, dynamic bouton redistribution along a broad axon backbone represents an unappreciated form of plasticity underlying developmental wiring and rewiring in the CNS

    Water-dispersible and quasi-superparamagnetic magnetite nanoparticles prepared in a weakly basic solution at the low synthetic temperature

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    Magnetite nanoparticles were prepared in a weakly basic solution at the low reaction temperature by the co-precipitation method. As a comparison, the oxidative precipitation method was also applied in this study. The structure, morphology, and other properties of the obtained samples were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), transmission electron microscope (TEM), and thermogravimetric analysis (TGA). The above characterization data indicate that small size and narrow size distribution are found for magnetite nanoparticles prepared by the co-precipitation method. Further magnetic property and Zeta potential results illuminate that magnetite nanoparticles prepared by this method display a quasi-superparamagnetic property and a good dispersion in the aqueous solution. Based on the investigation results, the magnetite nanoparticles with a quasi-superparamagnetic property and a fine dispersion can be facilely prepared in a weakly basic solution at the low reaction temperature by the co-precipitation method

    Diffusive gradients in thin-films (DGT) for in situ sampling of selected endocrine disrupting chemicals (EDCs) in waters

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    A passive water sampler based on the diffusive gradients in thin-films (DGT) technique was developed and tested for 3 groups of endocrine disrupting chemicals (EDCs, including oestrogens, alkyl-phenols and bisphenols). Three different resins (hydrophilic-lipophilic-balanced (HLB), XAD18 and Strata-XL-A (SXLA)) were investigated for their suitability as the binding phase for DGT devices. Laboratory tests across a range of pH (3.5–9.5), ionic strength (0.001–0.5 M) and dissolved organic matter concentration (0–20 mg L−1) showed HLB and XAD18-DGT devices were more stable compared to SXLA-DGT. HLB-DGT and XAD18-DGT accumulated test chemicals with time consistent with theoretical predictions, while SXLA-DGT accumulated reduced amounts of chemical. DGT performance was also compared in field deployments up to 28 days, alongside conventional active sampling at a wastewater treatment plant. Uptake was linear to the samplers over 18 days, and then began to plateau/decline, indicating the maximum deployment time in those conditions. Concentrations provided by the DGT samplers compared well with those provided by auto-samplers. DGT integrated concentrations over the deployment period in a way that grab-sampling cannot. The advantages of the DGT sampler over active sampling include: low cost, ease of simultaneous multi-site deployment, in situ analyte pre-concentration and reduction of matrix interferences compared with conventional methods. Compared to other passive sampler designs, DGT uptake is independent of flow rate and therefore allows direct derivation of field concentrations from measured compound diffusion coefficients. This passive DGT sampler therefore constitutes a viable and attractive alternative to conventional grab and active water sampling for routine monitoring of selected EDCs

    IDENTIFICATION AND QUANTIFICATION OF PINE NEEDLE ESSENTIAL OIL FROM DIFFERENT HABITATS AND SPECIES OF CHINA BY GC-MS AND GC METHOD

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    Background: Fresh pine needles, which evergreen, renewable and can be collected at any time, have abundant essential oil. The pine needle essential oil possess various biological activities, including antimicrobial, antioxidant, anti-inflammatory, cardioprotective properties etc., and can be widely used as medicine or medical raw materials, fragrances etc. So in order to make full use of pine needle plant resources, especially essential oil, the identification and quantification of essential oil were investigated. Materials and Methods: GC-MS was used to identified compounds in pine needle essential oil of Pinus massoniana Lamb. from Zhejiang, and GC method was developed for determining 5 compounds (namely α-pinene, β-pinene, limonene, bornyl acetate, β-caryophyllene) in pine needle essential oil from different habitats of Pinus massoniana Lamb. and different species (Pinus koraiensis Sieb. et Zucc., Pinus sylvestris var. mongolica Litv., Abies holophylla Maxim.). Hierarchical clustering analysis (HCA) was used to evaluate homogeneity of pine needles in China. Results: 42 compounds(monoterpenes and sesquiterpenes) were identified by GC-MS, which accounted for 99.62% of total essential oil, particularly contained α-and β-pinene (45.23%). Quantification results showed content of bornyl acetate were the lowest, while content of α-pinene, β-pinene were all high except Sichuan, among them α-pinene were higher than β-pinene except for Shandong and Jiangsu, and total content of essential oil in Guangxi is the highest, Jiangsu was the lowest within Pinus massoniana from different habitats. Within pine needle from different species, the highest total content was Pinus koraiensis, the lowest was Pinus sylvestris, Interestingly, the highest content of bornyl acetate was Abies holophylla. By HCA, samples were sorted into two clusters, Abies holophylla and the other, that is Abies holophylla is different from Pinus massoniana, Pinus koraiensis and Pinus sylvestris. Pinus massoniana from Sichuan is different from other Pinus, in which limonene was the highest in all samples. Conclusions: Compounds of pine needle essential oil vary greatly between genus, while smaller between species, so composition differences among pine needle essential oil was related with genus and species. Abies holophylla is different from other pinus species, and Pinus massoniana from Sichuan is different from other habitats. Pine needle essential oil contains abundant α-and β-pinene, which can be used as an alternative raw materials source of pinene. And Abies holophylla and Pinus massoniana from Sichuan can become bornyl acetate and limonene alternative source of raw materials

    Association between serum uric acid and colorectal cancer risk in European population: a two-sample Mendelian randomization study

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    ObjectivesThis study aimed to explore the potential causal associations between serum uric acid (SUA) and the risk of colorectal cancer, colon cancer and rectal cancer.MethodsTwenty-six SUA-related single nucleotide polymorphisms which were identified by a large meta-analysis of genome-wide association studies (GWASs) were used as instrumental variables in the two-sample Mendelian randomization (MR) study. Meta-analyses were used to synthesize the results of multiple GWASs which were extracted from the MRC Integrative Epidemiology Unit GWAS database for each type of cancer. The inverse variance weighted (IVW) method was used as the primary MR method to analyze the association between SUA and colorectal cancer risk. Several sensitivity analyses were performed to test the robustness of results.ResultsThe IVW method showed that there were no causal relationships between SUA and the risk of colorectal cancer [odds ratio (OR): 1.0015; 95% confidence interval (CI): 0.9975–1.0056] and colon cancer (OR: 1.0015; 95% CI: 0.9974–1.0055). The SUA levels were negative correlated with rectal cancer risk (OR: 0.9984; 95% CI: 0.9971–0.9998). The similar results were observed in both males (OR: 0.9987; 95% CI: 0.9975–0.9998) and females (OR: 0.9985; 95% CI: 0.9971–0.9999). The sensitivity analyses suggested no evidence of heterogeneity or horizontal pleiotropy. The leave-one-out analyses showed that one SNP (rs1471633) significantly drove the causal effect of SUA on rectal cancer risk. The MR-Egger regression and weighted median both showed that there were no causal relationships between SUA and the risk of colorectal cancer and its subtypes.ConclusionOverall, there was no linear causal association between SUA and the risk of colorectal cancer. However, further research is needed to investigate the role of higher SUA levels such as hyperuricemia or gout in the occurrence of colorectal cancer

    Development and validation of a three-dimensional deep learning-based system for assessing bowel preparation on colonoscopy video

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    BackgroundThe performance of existing image-based training models in evaluating bowel preparation on colonoscopy videos was relatively low, and only a few models used external data to prove their generalization. Therefore, this study attempted to develop a more precise and stable AI system for assessing bowel preparation of colonoscopy video.MethodsWe proposed a system named ViENDO to assess the bowel preparation quality, including two CNNs. First, Information-Net was used to identify and filter out colonoscopy video frames unsuitable for Boston bowel preparation scale (BBPS) scoring. Second, BBPS-Net was trained and tested with 5,566 suitable short video clips through three-dimensional (3D) convolutional neural network (CNN) technology to detect BBPS-based insufficient bowel preparation. Then, ViENDO was applied to complete withdrawal colonoscopy videos from multiple centers to predict BBPS segment scores in clinical settings. We also conducted a human-machine contest to compare its performance with endoscopists.ResultsIn video clips, BBPS-Net for determining inadequate bowel preparation generated an area under the curve of up to 0.98 and accuracy of 95.2%. When applied to full-length withdrawal colonoscopy videos, ViENDO assessed bowel cleanliness with an accuracy of 93.8% in the internal test set and 91.7% in the external dataset. The human-machine contest demonstrated that the accuracy of ViENDO was slightly superior compared to most endoscopists, though no statistical significance was found.ConclusionThe 3D-CNN-based AI model showed good performance in evaluating full-length bowel preparation on colonoscopy video. It has the potential as a substitute for endoscopists to provide BBPS-based assessments during daily clinical practice
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