detectability

可探测性
  • 文章类型: Journal Article
    花色是植物-传粉者相互作用的重要媒介。虽然来自花朵表面和背景的光的反射率受物理性质控制,这些信息的感知解释是由复杂的多层视觉处理产生的。如果花信号的定量建模力求通过参数简化实现可重复的一致性,或者建模应该反映已知蜜蜂处理信号的动态方式?我们讨论了为什么颜色是动物大脑对光谱信息的解释。不同的物种,或一个物种中的个体,可以根据感觉装置和/或个人经历对颜色信号作出不同的响应。人类和蜜蜂有不同的光谱范围,但是色彩理论强烈植根于人类的色彩感知,许多色彩视觉原理似乎很普遍。我们讨论了基于生理的蜜蜂颜色感知,神经解剖学和行为学证据为花朵颜色建模提供了途径。我们研究了在光谱不同背景下观看的花瓣和花卉指南是否应被视为简单的颜色对比问题,还是需要对蜜蜂如何做出感知决定进行更动态的考虑。我们讨论了诸如欺骗性兰花之类的植物可能会提供信号来利用蜜蜂的感知,而许多植物确实提供了诚实的信号,其中感知到的饱和度表明了向花朵中心收集营养奖励的可能性,从而促进了有效的授粉。
    Flower colour is an important mediator of plant-pollinator interactions. While the reflectance of light from the flower surface and background are governed by physical properties, the perceptual interpretation of such information is generated by complex multilayered visual processing. Should quantitative modelling of flower signals strive for repeatable consistency enabled by parameter simplification, or should modelling reflect the dynamic way in which bees are known to process signals? We discuss why colour is an interpretation of spectral information by the brain of an animal. Different species, or individuals within a species, may respond differently to colour signals depending on sensory apparatus and/or individual experience. Humans and bees have different spectral ranges, but colour theory is strongly rooted in human colour perception and many principles of colour vision appear to be common. We discuss bee colour perception based on physiological, neuroanatomical and behavioural evidence to provide a pathway for modelling flower colours. We examine whether flower petals and floral guides as viewed against spectrally different backgrounds should be considered as a simple colour contrast problem or require a more dynamic consideration of how bees make perceptual decisions. We discuss that plants such as deceptive orchids may present signals to exploit bee perception, whilst many plants do provide honest signalling where perceived saturation indicates the probability of collecting nutritional rewards towards the centre of a flower that then facilitates effective pollination.
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  • 文章类型: Journal Article
    近红外(NIR)染料具有与NIR区域中的光有利地相互作用的独特能力,这在隐身和伪装最重要的地方特别有趣,比如军装。使用可见NIR(Vis-NIR)和短波红外(SWIR)高光谱成像对NIR吸收染料染色的棉织物进行了表征。研究的目的是辨别染料浓度和染色温度变化引起的光谱变化,因为这些参数直接影响织物的颜色和摩擦牢度,从而影响伪装效果。在三种浓度(2.5、5和10%)和两种染色温度(55°C和85°C)下对织物进行染色,并对光谱进行主成分分析(PCA)和偏最小二乘判别分析(PLS-DA),以根据染料浓度区分织物。PCA模型根据染料浓度和染色温度成功地分离了织物,而PLS-DA模型在Vis-NIR范围内显示出75%至100%的分类精度。SWIR区域中的光谱不能用于检测NIR染料浓度的差异。这个发现很有希望,因为它与创建NIR染色伪装织物的目标一致,这些织物在不同的染料浓度下仍然无法区分。这些结果为进一步探索增强纺织品在军事应用中的隐身能力开辟了可能性。
    Near-infrared (NIR) dyes have a unique ability to interact favorably with light in the NIR region, which is particularly interesting where stealth and camouflage are paramount, such as in military uniforms. Characterization of cotton fabric dyed with NIR-absorbing dyes using visible-NIR (Vis-NIR) and short-wave infrared (SWIR) hyperspectral imaging was done. The aim of the study was to discern spectral changes caused by variations in dye concentration and dyeing temperature as these parameters directly influence color- and crocking-fastness of fabrics impacting the camouflage effect. The fabric was dyed at three concentrations (2.5, 5, and 10%) and two dyeing temperatures (55 °C and 85 °C) and principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) were performed on the spectra to discriminate the fabrics based on dye concentrations. The PCA models successfully segregated the fabrics based on the dye concentration and dyeing temperature, while PLS-DA models demonstrated classification accuracies between 75 and 100% in the Vis-NIR range. Spectra in the SWIR region could not be used to detect the differences in the concentrations of the NIR dyes. This finding is promising, as it aligns with the objective of creating NIR-dyed camouflage fabrics that remain indistinguishable under varying dye concentrations. These results open possibilities for further exploration in enhancing the stealth capabilities of textiles in military applications.
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  • 文章类型: Journal Article
    我们报告了来自地中海的非土著无脊椎动物的新数据(4个ostracods和20个软体动物),包括该盆地的五项新记录:近生动物Neomonoceratinainiqua,Neomonoceratinaaff.地中海,Neomonoceratinacf.熵,Loxoconchacf.gisellae(节肢动物:甲壳类动物)-地中海非本地陆生动物的第一个记录-和双壳类动物。对称(软体动物)。此外,我们首次报道了来自以色列的Electromavexillum,和库尔酶菌,Joculatorproblematicus,半特例,Pyrgulina娜娜,Pyrgulina微型块茎,Turbonillacangeyrani,AffMusculusaff.来自塞浦路斯的viridulus和Isignomon双色。我们还报告了Fossarussp的第二个记录。和Cerithiopsissp.cf.在地中海,来自塞浦路斯的Oscillagalilae的第一批活标本,以及以色列(和地中海)最北端的Garipallida记录。此外,我们报道了RugalucinaAngela的最早记录,地中海的Erviliascaliola和Alveinusmiliaceus,将它们在盆地的第一次出现追溯到3年、5年和7年,分别。我们提供了有关Spondylusnicobaricus和Nudiscintillaaff存在的新数据。glabra在以色列。最后,但重要的是,我们使用形态学和分子方法来修改地中海非本地Isognomon属的系统学,表明该盆地目前有两种物种共存:加勒比I.双色,分布在地中海中部和东部,还有印度太平洋I.aff.legumen,目前仅从地中海东部报道,其身份需要更深入的分类学研究。我们的工作表明需要分类学专业知识和调查,当NIS属于没有充分的分类学工作的分类单元时,有必要避免封闭命名法中的名称所赋予的毫无根据的自信感,以及必须继续收集样本,而不是依靠视觉普查和生物闪电战,以便能够准确检测非土著物种。
    We report new data on non-indigenous invertebrates from the Mediterranean Sea (four ostracods and 20 molluscs), including five new records for the basin: the ostracods Neomonoceratina iniqua, Neomonoceratina aff. mediterranea, Neomonoceratina cf. entomon, Loxoconcha cf. gisellae (Arthropoda: Crustacea)-the first records of non-indigenous ostracods in the Mediterranean-and the bivalve Striarca aff. symmetrica (Mollusca). Additionally, we report for the first time Electroma vexillum from Israel, and Euthymella colzumensis, Joculator problematicus, Hemiliostraca clandestina, Pyrgulina nana, Pyrgulina microtuber, Turbonilla cangeyrani, Musculus aff. viridulus and Isognomon bicolor from Cyprus. We also report the second record of Fossarus sp. and of Cerithiopsis sp. cf. pulvis in the Mediterranean Sea, the first live collected specimens of Oscilla galilae from Cyprus and the northernmost record of Gari pallida in Israel (and the Mediterranean). Moreover, we report the earliest records of Rugalucina angela, Ervilia scaliola and Alveinus miliaceus in the Mediterranean Sea, backdating their first occurrence in the basin by 3, 5 and 7 years, respectively. We provide new data on the presence of Spondylus nicobaricus and Nudiscintilla aff. glabra in Israel. Finally, yet importantly, we use both morphological and molecular approaches to revise the systematics of the non-indigenous genus Isognomon in the Mediterranean Sea, showing that two species currently co-occur in the basin: the Caribbean I. bicolor, distributed in the central and eastern Mediterranean, and the Indo-Pacific I. aff. legumen, at present reported only from the eastern Mediterranean and whose identity requires a more in-depth taxonomic study. Our work shows the need of taxonomic expertise and investigation, the necessity to avoid the unfounded sense of confidence given by names in closed nomenclature when the NIS belong to taxa that have not enjoyed ample taxonomic work, and the necessity to continue collecting samples-rather than relying on visual censuses and bio-blitzes-to enable accurate detection of non-indigenous species.
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  • 文章类型: Journal Article
    “甜羽扇豆”的种子在食品工业中发挥着越来越大的作用。羽扇豆蛋白质可用于生产各种食物,包括意大利面,面包,饼干,乳制品,咖啡替代品在一小部分人口中,食用羽扇豆可能会引起过敏反应,要么是由于对羽扇豆的原发性过敏,要么是由于与其他豆类的交叉过敏。因此,根据欧盟食品法规,羽扇豆必须在商业食品中申报。在这项研究中,我们研究了L.angustifolius品种“Boregine”的烘烤种子对十二烷基硫酸钠-聚丙烯酰胺凝胶电泳(SDS-PAGE)检测羽扇豆的影响,ELISAs,LC-MS/MS,和实时PCR。种子用流化床焙烧法焙烧,并在98°C至242°C范围内的种子表面温度下抽取样品。随着焙烧温度的升高,蛋白质和DNA的可提取性降低。此外,烘烤导致ELISA和LC-MS/MS对羽扇豆蛋白的可检测性降低,而实时PCR对DNA的可检测性降低。我们的结果表明,用于生产“羽扇豆咖啡”的烤羽扇豆种子的致敏性降低;然而,这必须在体内研究中得到证实。
    Seeds of \"sweet lupins\" have been playing an increasing role in the food industry. Lupin proteins may be used for producing a variety of foods, including pasta, bread, cookies, dairy products, and coffee substitutes. In a small percentage of the population, lupin consumption may elicit allergic reactions, either due to primary sensitization to lupin or due to cross-allergy with other legumes. Thus, lupin has to be declared on commercial food products according to EU food regulations. In this study, we investigated the influence of roasting seeds of the L. angustifolius cultivar \"Boregine\" on the detectability of lupin by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), ELISAs, LC-MS/MS, and real-time PCR. Seeds were roasted by fluidized bed roasting, and samples were drawn at seed surface temperatures ranging from 98 °C to 242 °C. With increasing roasting temperature, the extractability of proteins and DNA decreased. In addition, roasting resulted in lower detectability of lupin proteins by ELISAs and LC-MS/MS and lower detectability of DNA by real-time PCR. Our results suggest reduced allergenicity of roasted lupin seeds used for the production of \"lupin coffee\"; however, this has to be confirmed in in vivo studies.
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  • 文章类型: Journal Article
    Objective.在存在解剖背景噪声的情况下确定用于乳房X线照相术中的不同成像模态的目标的可检测性是具有挑战性的。这项工作提出了一种比较数字乳腺X线摄影(DM)中目标的图像质量和可检测性的方法,数字乳房断层合成(DBT)和合成乳房X线照相术。方法。使用带有丙烯酸球体的水模产生的低频结构化噪声来模拟不同类型图像的解剖背景噪声。开发了一种在这些条件下将非预白化观察者模型与眼睛滤镜(NPWE)一起应用的方法。使用具有0.2mm厚的铝盘的均匀聚(甲基)甲基丙烯酸酯模型来计算2D面内调制传递函数(MTF),噪声功率谱(NPS)噪声等效量,30、50和70mm厚度的系统检测量子效率。使用细钨丝确定DBT体积的深度MTF。MTF,在NPWE模型中使用系统NPS和解剖NPS来计算CDMAM体模中包含的金盘的阈值金厚度,作为参考。主要结果。NPWE模型与CDMAM体模之间的对应关系(线性Pearson相关性0.980)产生了阈值可检测性指数,该指数用于确定球形微钙化和质量的阈值直径。DBT成像改善了对质量的检测,这主要取决于解剖背景噪声的减少。相反,DM图像可以最好地检测微钙化。意义。这项研究中提出的方法能够量化不同成像方式和解剖背景噪声水平的图像质量和对象可检测性。
    Objective.Determining the detectability of targets for the different imaging modalities in mammography in the presence of anatomical background noise is challenging. This work proposes a method to compare the image quality and detectability of targets in digital mammography (DM), digital breast tomosynthesis (DBT) and synthetic mammography.Approach. The low-frequency structured noise produced by a water phantom with acrylic spheres was used to simulate anatomical background noise for the different types of images. A method was developed to apply the non-prewhitening observer model with eye filter (NPWE) in these conditions. A homogeneous poly(methyl) methacrylate phantom with a 0.2 mm thick aluminium disc was used to calculate 2D in-plane modulation transfer function (MTF), noise power spectrum (NPS), noise equivalent quanta, and system detective quantum efficiency for 30, 50 and 70 mm thicknesses. The in-depth MTFs of DBT volumes were determined using a thin tungsten wire. The MTF, system NPS and anatomical NPS were used in the NPWE model to calculate the threshold gold thickness of the gold discs contained in the CDMAM phantom, which was taken as reference. Main results.The correspondence between the NPWE model and the CDMAM phantom (linear Pearson correlation 0.980) yielded a threshold detectability index that was used to determine the threshold diameter of spherical microcalcifications and masses. DBT imaging improved the detection of masses, which depended mostly on the reduction of anatomical background noise. Conversely, DM images yielded the best detection of microcalcifications.Significance.The method presented in this study was able to quantify image quality and object detectability for the different imaging modalities and levels of anatomical background noise.
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  • 文章类型: Journal Article
    脉冲回波模式的超声波无损评估用于单搭接铝粘合接头的检查,在键合区域包含界面缺陷。该研究的目的是除了确保准确估计缺陷尺寸之外,还增加了缺陷检测的可能性。为了实现这一点,这项研究探索了其他超声特征(不仅是振幅),可以提供有关结构质量和界面缺陷存在的更准确信息。在这项工作中,两种类型的界面缺陷,即夹杂物和分层,基于提取的超声特征进行研究,以评估缺陷检测的预期可行性及其性能评价。此外,对多个界面反射的分析,这在我们以前的工作中已经被证明可以改善检测,与各种超声特征的提取一起应用,因为它可以增加缺陷检测的概率。确定了每种缺陷类型具有最佳性能的超声特征,并进行了比较分析,表明与分层相比,尺寸夹杂型缺陷更具挑战性。最佳性能是观察到的特征,如峰峰值幅度,比率系数,绝对能量,绝对飞行时间,振幅的平均值,标准偏差值,和变异系数两种类型的缺陷。与这些特征的真实缺陷相比,缺陷尺寸的最大相对误差为夹杂物的16.9%和分层的3.6%,最小误差为11.4%和2.2%,分别。此外,确定了对来自样品界面的重复反射数据的分析,即,铝粘合剂的第二和第三反射,这些有助于增加缺陷检测的可能性。
    Ultrasonic non-destructive evaluation in pulse-echo mode is used for the inspection of single-lap aluminum adhesive joints, which contain interface defects in bonding area. The aim of the research is to increase the probability of defect detection in addition to ensuring that the defect sizes are accurately estimated. To achieve this, this study explores additional ultrasonic features (not only amplitude) that could provide more accurate information about the quality of the structure and the presence of interface defects. In this work, two types of interface defects, namely inclusions and delaminations, were studied based on the extracted ultrasonic features in order to evaluate the expected feasibility of defect detection and the evaluation of its performance. In addition, an analysis of multiple interface reflections, which have been proved to improve detection in our previous works, was applied along with the extraction of various ultrasonic features, since it can increase the probability of defect detection. The ultrasonic features with the best performance for each defect type were identified and a comparative analysis was carried out, showing that it is more challenging to size inclusion-type defects compared to delaminations. The best performance is observed for the features such as peak-to-peak amplitude, ratio coefficients, absolute energy, absolute time of flight, mean value of the amplitude, standard deviation value, and variation coefficient for both types of defects. The maximum relative error of the defect size compared to the real one for these features is 16.9% for inclusions and 3.6% for delaminations, with minimum errors of 11.4% and 2.2%, respectively. In addition, it was determined that analysis of the data from repetitive reflections from the sample interface, namely, the aluminum-adhesive second and third reflections, that these contribute to an increase in the probability of defect detection.
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  • 文章类型: Journal Article
    慢地震的尺度定律,这是地震矩和持续时间之间的线性关系,是在15年前提出的,并发起了一场关于控制缓慢与缓慢的物理过程差异的辩论。快速(普通)地震。根据新的观察,在一个广泛的时期范围内,我们证明慢地震的线性标度仍然有效,但作为~1013Nm/s的力矩速率的明确定义的上限。慢速地震和快速地震的缩放比例之间的力矩率差距仍然没有填补。慢地震发生在可探测阈值附近,这样我们就无法以较低的力矩率检测变形事件。在缓慢地震类别中观察到的趋势支持了这样一种观点,即这个不可观察的领域充满了较低力矩率的事件。这表明观点发生了变化-建议的缩放应被视为一个界限,或速度限制,缓慢的地震我们认为慢地震代表扩散传播,并且定矩率反映了这些扩散过程速度的上限。普通地震,相比之下,发生在地震波传播和断裂之间的耦合过程。因此,即使这两种现象都以剪切滑移的形式出现,缩放的差异反映了控制传播的物理过程的差异。
    The scaling law for slow earthquakes, which is a linear relationship between seismic moment and duration, was proposed 15 y ago and initiated a debate on the difference in physical processes governing slow vs. fast (ordinary) earthquakes. Based on new observations across a wide period range, we show that linear scaling of slow earthquakes remains valid, but as a well-defined upper bound on moment rate of ~1013 Nm/s. The large gap in moment-rate between the scaling of slow and fast earthquakes remains unfilled. Slow earthquakes occur near the detectability threshold, such that we are unable to detect deformation events with lower moment rates. Observed trends within slow earthquake categories support the idea that this unobservable field is populated with events of lower moment rate. This suggests a change in perspective - that the proposed scaling should be considered as a bound, or speed limit, on slow earthquakes. We propose that slow earthquakes represent diffusional propagation, and that the bound on moment rate reflects an upper limit on the speed of those diffusional processes. Ordinary earthquakes, in contrast, occur as a coupled process between seismic wave propagation and fracture. Thus, even though both phenomena occur as shear slip, the difference of scaling reflects a difference in the physical process governing propagation.
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  • 文章类型: Journal Article
    视觉注意力对工作中的许多任务至关重要。当它受损时,职业事故的风险增加。潜在的事故预防将是跟踪员工的注意力状态,以构建休息制度。在计算机显示器(CM)上进行的视觉注意力测试很有前途,与广泛使用的连续性能测试相比,在检测职业环境中的注意力不集中方面具有几个优点。然而,因为在特定的工作环境中使用CM的设置是不切实际的(例如,缺乏空间或令人不安的暴露于光线),该测试是在头戴式显示器(HMD)中实施的。这项研究旨在调查测试的HMD版本是否是CM版本的合适替代品。为此,参与者(N=30;20-29岁)进行了两项测试。HMD上的性能明显低于CM。此外,将这些表现与之前研究中使用CM记录的规范数据进行比较.这些数据与本研究中CM记录的数据显着不同。这强调了标准化测试环境的重要性,可以由HMD提供。最后,这项研究表明,新的VR工具,基于先前旨在评估复杂视觉环境中的视觉技能的测试,在可靠性方面表现出良好的心理测量特性。Inadditional,没有发现关于HMD的功能和可用性的问题。
    Visual attention is crucial to many tasks during working. When it is impaired, the risk of occupational accidents is increased. A potential accident prevention would be the tracking of employees\' attentional states to construct break regimes. There is a promising visual attention test administered on a computer monitor (CM) that has several advantages over widely used continuous performance tests in detecting inattentiveness in occupational environments. However, as the setup with a CM is impractical for the use in particular working environments (e.g., lack of space or disturbing exposure to light), the test was implemented into a head-mounted display (HMD). This study aimed to investigate whether the HMD version of the test is a suitable alternative to the CM version. For this purpose, participants (N = 30; 20-29 y) performed both tests. The performance on the HMD was significantly lower than on the CM. Moreover, the performances were compared with normative data recorded with a CM in a previous study. These data significantly differ from the data recorded with the CM in the present study. This emphasizes the importance of a standardized test environment, which could be provided by an HMD. Conclusively, this study revealed that the new VR tool, based on a previous test designed to assess visual skills in a complex visual environment, exhibited good psychometric property regarding the reliability. In additional, no problems were revealed regarding the functionality and usability of the HMD.
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  • 文章类型: Journal Article
    对于非常小的物体的检测,高分辨率探测器有望提供更高的剂量效率。我们通过比较高分辨率和标准分辨率(具有2×2合并和较大的焦斑)模式下的可检测性,评估了分辨率增加对临床光子计数探测器CT(PCD-CT)的影响。将50μm细的金属线放置在胸部体模中,并在两种模式下以三种曝光水平(12、15和18mAs)进行扫描;使用三个重建内核(Br40,Br68和Br76,从平滑到尖锐)重建采集的数据。扫描非预白化模型观察者独立地搜索每个切片中的导线位置。检测性能定量为自由响应ROC曲线的指数变换下的面积。对于Br40,Br68和Br76,高分辨率模式在18mAs处的平均AUC分别为0.45,0.49和0.65,两次,3.6倍,和4.6倍的标准分辨率模式。对于每个重建内核,高分辨率模式在12mAs时比标准分辨率模式在18mAs时获得更大的AUC,但在更锋利的内核下,改进更大。结果与高分辨率CT在较高频率下预期的噪声混叠的更大抑制一致。这项工作说明了PCD-CT可以为小型检测任务提供大剂量效率增益,高对比度病变。
    For the detection of very small objects, high resolution detectors are expected to provide higher dose efficiency. We assessed this impact of increased resolution on a clinical photon counting detector CT (PCD-CT) by comparing its detectability in high resolution and standard resolution (with 2×2 binning and larger focal spot) modes. A 50μm-thin metal wire was placed in a thorax phantom and scanned in both modes at three exposure levels (12, 15, and 18 mAs); acquired data were reconstructed with three reconstruction kernels (Br40, Br68, and Br76, from smooth to sharp). A scanning nonprewhitening model observer searched for the wire location within each slice independently. Detection performance was quantified as area under the exponential transform of the free response ROC curve. The high-resolution mode had the mean AUCs at 18 mAs of 0.45, 0.49, and 0.65 for Br40, Br68, and Br76, respectively, which were 2 times, 3.6 times, and 4.6 times those of the standard resolution mode. The high-resolution mode achieved greater AUC at 12 mAs than the standard resolution mode at 18 mAs for every reconstruction kernel, but improvements were larger at sharper kernels. The results are consistent with the greater suppression of noise aliasing expected at higher frequencies with high resolution CT. This work illustrates that PCD-CT can provide large dose efficiency gains for detection tasks of small, high contrast lesions.
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  • 文章类型: Journal Article
    目的:评估自动管电流调制(ATCM)对双源CT(DSCT)中虚拟单能量图像(VMI)质量的影响。
    方法:使用Mercury体模在DSCT上进行采集。使用单能量CT(SECT)和双能量CT(DECT)成像的腹部骨盆检查的采集参数。使用固定mAs和ATCM对每种成像模式进行采集。设置mAs值以在固定mAs采集中获得11mGy的体积CT剂量指数。该值用作ATCM采集中的参考mAs。在VMI和SECT图像上计算了40、50、60和70keV水平的噪声功率谱和基于任务的传递函数。计算碘浓度为10mg/mL的病变的可检测性指数(d')。
    结果:对于所有能量水平和截面直径为21,26和31厘米,ATCM系统在VMI上的噪声幅度高于固定mAs。两种成像模式的固定mAs和ATCM采集之间的噪声纹理和空间分辨率相似。使用ATCM的所有能量水平的d值都比使用21和26厘米直径的固定mAs采集的d值低-39.82±9.32%,直径31厘米时相似-4.13±0.24%,直径36厘米时更高10.40±6.69%。与SECT图像相比,在所有能级的VMI上都更高。
    结论:与固定mAs和SECT相比,ATCM系统可以与DECT成像一起使用,以优化患者暴露,而不会改变VMI的噪声纹理和空间分辨率。
    OBJECTIVE: To assess the impact of the automatic tube current modulation (ATCM) on virtual monoenergetic images (VMIs) quality in dual-source CT(DSCT).
    METHODS: Acquisitions were performed on DSCT using the Mercury phantom. The acquisition parameters for an abdomen-pelvic examination with single-energy CT(SECT) and dual-energy CT(DECT) imaging were used. Acquisitions were performed for each imaging mode using fixed mAs and ATCM. The mAs value was set to obtain a volume CT dose index of 11 mGy in fixed mAs acquisitions. This value was used as the reference mAs in ATCM acquisitions. The noise power spectrum and task-based transfer function at 40,50,60 and 70 keV levels were computed on VMIs and SECT images. The detectability index (d\') was calculated for a lesion with an iodine concentration of 10 mg/mL.
    RESULTS: The noise magnitude on VMIs was higher with the ATCM system than with fixed mAs for all energy levels and section diameters of 21,26 and 31 cm. The noise texture and spatial resolution were similar between the fixed mAs and ATCM acquisitions for both imaging modes. The d\' values were lower for all energy levels with ATCM than with fixed mAs acquisitions for 21 and 26 cm diameters by -39.82 ± 9.32%, similar at 31 cm diameter -4.13 ± 0.24% and higher at 36 cm diameter 10.40 ± 6.69%. It was higher on VMIs at all energy levels compared to SECT images.
    CONCLUSIONS: The ATCM system could be used with DECT imaging to optimize patient exposure without changing the noise texture and spatial resolution of VMIs compared to fixed mAs and SECT.
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