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Dr Sarah E. Medland Daniel A. Park Danuta Z. Loesch Nicholas G. Martin 《Annals of human biology》2013,40(4):504-517
Finger ridge count is a valuable quantitative phenotype used in a wide range of biological and anthropological research. However, the scoring of the phenotype is both labour intensive and error prone. This paper describe a freely available software program, RIDGECOUNTER, that can be used to obtain ridge counts from digitized prints (either collected using a digital fingerprint scanner or scanned from an inked print). The program yields semi-automated ridge counts and logs the location of the user-selected core and delta points to aid in the training of new researchers and ensure the repeatability of count. In a validity study of 451 prints, the semi-automated ridge counts of digital prints showed good agreement (r?=?0.957) with traditional manual counts of inked-rolled prints (which were obtained 2 years apart and counted by different researchers). In a reliability study of 200 prints, semi-automated ridge counts derived from digital prints collected at two different time points also showed good agreement (r?=?0.962) (the prints were obtained 2 years apart and counted by the same researcher). Although designed for use with fingerprints, the program is suitable for use with palm, foot or toe prints using user-defined landmarks. 相似文献
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目的 比较2种目前放疗市场上主流的形变配准软件在CT形变配准中的结果表现,确定其在图像配准中的价值。方法 选择本院2018年2月—2020年6月收治的15例重复定位的头颈部肿瘤患者作为研究对象,治疗过程中前、后2组CT图像正常组织由同一位资深医师进行勾画,分别在MIM软件和AccuContour软件中进行形变配准,将第一组图像的正常组织形变到第二组图像中,与第二组图像直接勾画的组织进行计算,得到相似性系数(Dice系数)与空间评价指标(Hausdorff距离)。采用SPSS 23.0软件包对数据进行统计学分析。结果 2种形变配准软件都有良好的形变配准功能。正常组织显像不同,对配准结果有一定影响,眼球、下颌骨等显像良好的组织配准结果更好,晶体、视神经、视交叉等小体积组织配准结果较差。2组软件相比,MIM软件更具有优势;Dice系数评价中,MIM软件数据更佳的比率为67%,其中55%存在统计学意义(P<0.05);Hausdorff距离显示,MIM软件数据更佳的比率为74%,其中48%的指标存在统计学意义(P<0.05)。结论 2种形变配准软件都具备良好的形变配准能力,相对而言,MIM软件更有优势。对形变配准精度要求较高时,选择MIM软件更佳。 相似文献
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Rachelle Steyn John Boniaszczuk Theodore Geldenhuys 《Cardiovascular journal of Africa》2014,25(2):44-49
Serial measurement of LVEF using gated blood pool (GBP) imaging is an established technique for monitoring LVEF in patients undergoing chemotherapy with cardiotoxic medication and in patients after heart transplants.11,2 The nuclear medicine department at Groote Schuur Hospital performs up to a thousand GBP studies annually. The majority of these studies are for patients receiving cardiotoxic chemotherapy and have a significant impact on patient management.In our hospital, the radiation oncologists consider not starting cardiotoxic chemotherapy if the LVEF is below 50% and terminating chemotherapy if there is a 10% decrease. In patients who have had heart transplants, the cardiologists start patients on glucocorticosteroids if a patient’s LVEF decreases by10%. It is therefore imperative that serial studies on an individual patient are comparable.Two software systems are used in our nuclear medicine department. The Siemens system (Siemens Medical Solutions, Chicago, USA) was introduced in February 2006 and the Hermes system (Hermes Medical Solutions, Stockholm Sweden) in September 2007. After the introduction of the Hermes system, we found large differences between the LVEFs calculated by the two systems. This was confirmed by a pilot study and is consistent with the literature that different software programs for processing equilibrium gated radionuclide studies cannot be used interchangeably.3-7The department also uses two different cameras, a General Electric (GE) Starcam 400 AC single-head and a Siemens Signature Series e.cam dual-head camera to acquire the raw data. These are then transferred to the Siemens and Hermes processing systems.This study was done to determine how the software packages used for processing GBP studies should be integrated into our department and if the use of different cameras for acquisition influences results. The study had two components. The first examined the values and reproducibility of estimates of LVEF from two software packages using data acquired on the GE gamma camera and processed independently by three operators. The second component examined the values and reproducibility of estimates of LVEF calculated with the same software packages using matched pairs of raw data acquired on both gamma cameras (GE and Siemens) processed by one operator. 相似文献
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Forensic odontology plays an important role in human identification and dental age estimation is an integral part of this process. The aim of the study was to investigate the association between chronological age and pulp/tooth volume ratio in a Malaysian population (Malays and Chinese) from cone-beam computed tomography (CBCT) scans, enhanced with Mimics software. Three hundred CBCT scans of 153 males and 147 females, aged between 16 and 65 years were divided into 5 age groups. Volumetric analysis of the pulp/tooth ratio was performed in maxillary left canines, maxillary right canines and maxillary right central incisors. Simple linear regression and Pearson correlation analysis indicated the strongest coefficient of correlation (R) values for maxillary right central incisors (0.83) followed by maxillary right canines (0.74) and maxillary left canines (0.73). Fisher’s Z test indicated that dental age estimation is gender independent. The derived regression equations were further validated on an independent group of 126 teeth. The results indicated mean absolute error (MAE) values of 6.48 and 8.58 years for maxillary right central incisors and maxillary canines respectively. It was also noticed that MAE values were higher among the age groups ranging from 46 to 65 years. This study showed that a volumetric change in the pulp cavity with age is a valuable assessment method for dental age estimation among Malaysian population. 相似文献
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Dynamic contrast‐enhanced MRI: Study of inter‐software accuracy and reproducibility using simulated and clinical data 下载免费PDF全文
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生物相关性溶出度方法研究进展 总被引:1,自引:1,他引:0
摘要:建立具有生物相关性的溶出度方法目的在于通过理想的体外溶出试验预测体内药代动力学过程。近年来,研究表明在生物相关性溶出介质中选择合适的溶出装置进行溶出试验得到的溶出曲线能较好地反映其在体内的溶出行为,计算机模拟软件可为建立合理的体外溶出度方法提供指导和依据。通过采用合适的生物相关性溶出介质、溶出装置,结合计算机模拟软件可建立A级水平的IVIVC(in vitro-in vivo correlation),可能代替生物等效性研究。 相似文献
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Dong Kyu Lim Changyeun Mo Dong-Kyu Lee Nguyen Phuoc Long Jongguk Lim Sung Won Kwon 《Yao wu shi pin fen xi = Journal of food and drug analysis.》2018,26(1):260-267
The authenticity determination of white rice is crucial to prevent deceptive origin labeling and dishonest trading. However, a non-destructive and comprehensive method for rapidly discriminating the geographical origins of white rice between countries is still lacking. In the current study, we developed a volatile organic compound based geographical discrimination method using headspace solid-phase microextraction coupled to gas chromatography–mass spectrometry (HS-SPME/GC–MS) to discriminate rice samples from Korea and China. A partial least squares discriminant analysis (PLS-DA) model exhibited a good classification of white rice between Korea and China (accuracy = 0.958, goodness of fit = 0.937, goodness of prediction = 0.831, and permutation test p-value = 0.043). Combining the PLS-DA based feature selection with the differentially expressed features from the unpaired t-test and significance analysis of microarrays, 12 discriminatory biomarkers were found. Among them, hexanal and 1-hexanol have been previously known to be associated with the cultivation environment and storage conditions. Other hydrocarbon biomarkers are novel, and their impact on rice production and storage remains to be elucidated. In conclusion, our findings highlight the ability to rapidly discriminate white rice from Korea and China. The developed method maybe useful for the authenticity and quality control of white rice. 相似文献