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Fourier transform infrared (FTIR) spectroscopic imaging is an emerging microscopy modality for clinical histopathologic diagnoses as well as for biomedical research. Spectral data recorded in this modality are indicative of the underlying, spatially resolved biochemical composition but need computerized algorithms to digitally recognize and transform this information to a diagnostic tool to identify cancer or other physiologic conditions. Statistical pattern recognition forms the backbone of these recognition protocols and can be used for highly accurate results. Aided by biochemical correlations with normal and diseased states and the power of modern computer-aided pattern recognition, this approach is capable of combating many standing questions of traditional histology-based diagnosis models. For example, a simple diagnostic test can be developed to determine cell types in tissue. As a more advanced application, IR spectral data can be integrated with patient information to predict risk of cancer, providing a potential road to precision medicine and personalized care in cancer treatment. The IR imaging approach can be implemented to complement conventional diagnoses, as the samples remain unperturbed and are not destroyed. Despite high potential and utility of this approach, clinical implementation has not yet been achieved due to practical hurdles like speed of data acquisition and lack of optimized computational procedures for extracting clinically actionable information rapidly. The latter problem has been addressed by developing highly efficient ways to process IR imaging data but remains one that has considerable scope for progress. Here, we summarize the major issues and provide practical considerations in implementing a modified Bayesian classification protocol for digital molecular pathology. We hope to familiarize readers with analysis methods in IR imaging data and enable researchers to develop methods that can lead to the use of this promising technique for digital diagnosis of cancer. 相似文献
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《Current biology : CB》2020,30(13):2616-2620.e2
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ABSTRACT This paper focuses on sound production in the larvae of Geotrupes spiniger (Marsham) (Coleoptera: Geotrupidae). A single stridulatory apparatus was identified and then analysed from a structural point of view. Sound was studied using spectography and results included a quantitative analysis with characterizing physical parameters. Results highlight the need to study stridulation in Geotrupidae more in detail, to improve our understanding of its evolutionary and biological meaning. 相似文献
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To visualize phytohormone localization in plant tissues, transgenic plants comprising the GUS reporter gene are often used. However, until now only qualitative assessment of the hormone presence was available. In this work, we suggested the method for IAA quantification in transgenic DR5::GUS Arabidopsis thaliana L. plants by the analysis of digital images. An empirical quadratic dependence was established between the IAA concentration in medium and the level of GUS-dependent staining. Using this method, we demonstrated that, after A. thaliana root gravistimulation for 90 min, auxin lateral redistribution occurred. It resulted in the increase in the IAA concentration in the lower root part (in the elongation zone and apical meristem) by 200% on the average. 相似文献
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PurposeTo evaluate the use of pseudo-monoenergetic reconstructions (PMR) from dual-energy computed tomography, combined with the iterative metal artefact reduction (iMAR) method.MethodsPseudo-monoenergetic CT images were obtained using the dual-energy mode on the Siemens Somatom Definition AS scanner. A range of PMR combinations (70–130 keV) were used with and without iMAR. A Virtual Water™ phantom was used for quantitative assessment of error in the presence of high density materials: titanium, alloys 330 and 600. The absolute values of CT number differences (AD) and normalised standard deviations (NSD) were calculated for different phantom positions. Image quality was assessed using an anthropomorphic pelvic phantom with an embedded hip prosthesis. Image quality was scored blindly by five observers.ResultsAD and NSD values revealed differences in CT number errors between tested sets. AD and NSD were reduced in the vicinity of metal for images with iMAR (p < 0.001 for AD/NSD). For ROIs away from metal, with and without iMAR, 70 keV PMR and pCT AD values were lower than for the other reconstructions (p = 0.039). Similarly, iMAR NSD values measured away from metal were lower for 130 keV and 70 keV PMR (p = 0.002). Image quality scores were higher for 70 keV and 130 keV PMR with iMAR (p = 0.034).ConclusionThe use of 70 keV PMR with iMAR allows for significant metal artefact reduction and low CT number errors observed in the vicinity of dense materials. It is therefore an attractive alternative to high keV imaging when imaging patients with metallic implants, especially in the context of radiotherapy planning. 相似文献
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Deborah Lupton 《Bioethics》2020,34(9):969-976
Digital health technologies are often advocated as a way of helping people monitor, promote and manage their health, care for others and reduce the burden on healthcare systems. Yet these technologies have also been subject to criticism for limiting human flourishing and exacerbating socioeconomic disadvantage. Bioethical appraisals of digital health technologies tend to take a conventional risk-benefit approach, positioning the human subject as a rational, autonomous agent who is acted on by technologies. In this paper, I present a case for adopting an alternative more-than-human perspective on bioethics. A more-than-human approach considers human-technological assemblages and agencies as distributed, relational, situated and emergent. To illustrate the insights that this perspective can offer, I draw on the findings of four empirical projects I have conducted on people’s use of digital devices and platforms used for health-related purposes, including social media groups and online forums, mobile apps and wearable devices. I conclude with the argument that a more-than-human approach to bioethics can begin to incorporate a new ‘zoë ethics’ that can acknowledge and address the deeper affective, multisensory and relational dimensions of humans’ encounters with and enactments of material things and nonhuman creatures. 相似文献
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数字照片在树干解析上的应用 总被引:2,自引:0,他引:2
介绍了一种利用摄影测量技术开展树干解析的新方法.通过求算横截面积,换算成理论直径及年轮宽度.此法可以提高测量精度,特别是在树干横截面不规则的情况下,可以提高准确度.选择一个基本圆满的圆盘,直接测量直径和由面积换算比较年轮宽度,二者差异平均为10%,最大达32%.由于图像上直接测量的是面积,树皮的横截面可以更加准确获得,而传统的方法无法克服这个缺点.数字照片还是储存年轮信息的理想形式,便于保存和复查.本法使用的是普通的数码照片,方便适用,是开展森林精密测量简单易行手段. 相似文献
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Charles F. Hildebolt Jane E. Phillips-Conroy Clifford J. Jolly Jeffrey Schaeffer 《American journal of primatology》1993,29(1):61-72
Radiograph-based methods were used to assess alveolar bone loss in 12 juvenile and 18 adult baboons (Papio hamadryas, sensu lato) living in the Awash National Park, Ethiopia. Alveolar bone loss, as measured from the cementoenamel junction to the alveolar crest, averaged about 1 mm in juveniles and about 1.5 mm in adults. Densitometry of alveolar bone from the radiographs provides a baseline for comparisons with other adult baboons. Periodontal disease surveys of baboon populations using such methods may identify potential etiological agents. Such knowledge may contribute to a better understanding of periodontal disease etiology in humans. © 1993 Wiley-Liss, Inc. 相似文献
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