scholarly journals Reproducibility of calcium scoring of the coronary arteries: comparison between different vendors and iterative reconstructions

2020 ◽  
Vol 9 (4) ◽  
pp. 205846012092214
Author(s):  
Kyu Sung Choi ◽  
Whal Lee ◽  
Joon Hyung Jung ◽  
Eun-Ah Park
Keyword(s):  
Cardiac Risk ◽  
Rank Test ◽  
Calcium Scoring ◽  
Reconstruction Algorithms ◽  
Asymptomatic Patients ◽  
Significant Difference ◽  
Siemens Scanner ◽  
Signed Rank Test ◽  
Ct Scanners ◽  
The Difference

Background The coronary artery calcium scoring (CCS) has been widely used for cardiac risk stratification for asymptomatic patients. Purpose To assess the reproducibility of CCS performed on four different computed tomography (CT) scanners, and compare the variability between two reconstruction algorithms, filtered back projection (FBP), and iterative reconstruction (IR). Material and Methods A CCS phantom was made from agar and contained 23 pieces of chicken bones. The phantom was repeatedly scanned using four different CT scanners: Toshiba; GE; Philips; and Siemens. Images were reconstructed using FBP and IR. Agatston and volume scores of total bone fragments were calculated and the overall differences between the instruments were evaluated using the Friedman test. Comparison of the Agatston and volume scores between the two reconstruction algorithms, for each instrument, was evaluated using the Wilcoxon signed rank test. Results The difference in the Agatston scores was significantly different between the four machines ( P = 0.001). The Toshiba scanner yielded the highest score followed by Philips, GE, and Siemens scanners. There was no difference in the CCS evaluated using the two reconstruction algorithms, except in case of the Siemens scanner ( P = 0.032). Conclusion CCS performed on different scanners varied significantly. In the Toshiba, Philips, and GE scanners, there was no significant difference in the CCS determined using either an IR or the FBP algorithm. In the Siemens scanner, applying the IR algorithm resulted in a slightly different scores, which might not be clinically significant.

Utility of T2 mapping in the staging of thyroid-associated ophthalmopathy: efficiency of region of interest selection methods

2020 ◽  
Vol 61 (11) ◽  
pp. 1512-1519 ◽  
Author(s):  
Wen Chen ◽  
Hao Hu ◽  
Huan-Huan Chen ◽  
Guo-Yi Su ◽  
Tao Yang ◽  
...  
Keyword(s):  
T2 Mapping ◽  
Region Of Interest ◽  
Roc Curves ◽  
Rank Test ◽  
Selection Methods ◽  
Measuring Time ◽  
Significant Difference ◽  
Thyroid Associated Ophthalmopathy ◽  
Signed Rank Test ◽  
The Difference

Background Discriminating the stage of thyroid-associated ophthalmopathy (TAO) is crucial for the treatment strategy and prognosis prediction. Utility of conventional magnetic resonance imaging in the disease staging is limited. Purpose To investigate the performance of T2 mapping based on different region of interest (ROI) selection methods in the staging of TAO. Material and Methods Thirty-two patients with TAO were retrospectively enrolled. Two radiologists independently measured the T2 relaxation time (T2RT) of extraocular muscles using two different ROIs (hotspot [ROIHS]: T2RT-hot; single-slice [ROISS]: T2RT-mean, T2RT-max, T2RT-min). Independent-samples t test, Wilcoxon signed rank test, Spearman correlation analysis, receiver operating characteristic (ROC) curves analyses, multiple ROC comparisons, and intra-class correlation coefficient (ICC) were used for statistical analyses. Results No significant difference was found in the measuring time between ROIHS and ROISS methods ( P = 0.066). T2RT-mean demonstrated the highest ICC for measurement, followed by T2RT-max and T2RT-min, and T2RT-hot showed the poorest reproducibility. Active TAOs showed significantly higher values for all the T2RTs than inactive mimics (all P < 0.001). Significant positive correlations were found between T2RTs and CAS (all P < 0.005). T2RT-hot and T2RT-max showed significantly higher areas under the curve than that of T2RT-mean ( P = 0.013 and 0.024, respectively), while the difference between T2RT-hot and T2RT-max was not significant ( P = 0.970). Conclusion The T2RTs derived from both ROI selection methods could be useful for the staging of TAO. The results of measuring time, reproducibility, and diagnostic performance suggest that T2RT-max would be the optimal indicator for staging.

scholarly journals Stereoacuity of Black-White and Red-Green Patterns in Individuals with and without Color Deficiency

2018 ◽  
Vol 2018 ◽  
pp. 1-4 ◽  
Author(s):  
Ying Sun ◽  
Huang Wu ◽  
Yinghong Qiu ◽  
Zhiqiang Yue
Keyword(s):  
Color Vision ◽  
Test System ◽  
Influential Factor ◽  
Rank Test ◽  
Chromatic Contrast ◽  
Normal Color Vision ◽  
Significant Difference ◽  
Signed Rank Test ◽  
Color Deficiency ◽  
The Difference

Background. Chromatic contrast may affect stereopsis. Daltonism is a common color deficiency in which the colors red and green are incorrectly detected. The aim of this study was to evaluate the stereoacuity of color-defective individuals presented with color symbols that they see defectively. Methods. Ten students diagnosed with daltonism and 10 students with normal color vision were recruited. A stereopsis test system using a phoropter and two 4K smartphones was used. Contour-based graphs and random-dot graphs with black versus white and red versus green patterns were used as test symbols. The Wilcoxon signed rank test was used to test the difference between groups. Results. No significant difference in stereoacuity was found between contour-based and random-dot graphs within both daltonism cohort and normal color vision cohort (P>0.05). A significant difference in stereoacuity was found between the black-white (P=0.005) and red-green (P=0.007) graphs for the daltonism cohort, while no significant difference in stereoacuity was found for the normal color vision cohort (P>0.05). Conclusion. Chromatic contrast is an influential factor for stereopsis measurement in individuals with color deficiency.

scholarly journals Occupant Awareness towards the Application of Total Productive Maintenance in Green Office Building

2021 ◽  
Author(s):  
Cheong Peng Au-Yong ◽  
◽  
Nik Elyna Myeda ◽  
Nur Farhana Azmi ◽  
◽  
...  
Keyword(s):  
Descriptive Analysis ◽  
Green Building ◽  
Rank Test ◽  
Total Productive Maintenance ◽  
Operation And Maintenance ◽  
Significant Difference ◽  
Signed Rank Test ◽  
Maintenance Activities ◽  
The Difference ◽  
Total Participation

Total productive maintenance (TPM) can be beneficial to be applied in green building. Successful TPM application requires total participation of the occupants in green building. However, lack of occupant awareness and involvement are the barriers of TPM application in green building. Thus, this paper aims to examine the aspects of occupant awareness and occupant involvement in operation and maintenance of green building. A questionnaire survey was performed among the occupants of green office buildings in Malaysia with 417 valid responses. Descriptive analysis was used to identify the level of occupant awareness and involvement in the operation and maintenance activities. Then, Wilcoxon signed-rank test was run to examine the difference between occupant awareness and occupant involvement in the operation and maintenance activities. The results have demonstrated significant difference between the occupant awareness and occupant involvement, whereby the levels of occupant awareness aspects were above average, while the level of occupant involvement was below average. Since TPM concept in green building aims for total participation of occupants in operation and maintenance activities, the increase of occupant involvement is necessary. The occupants will be confident to take part in operation and maintenance activities if they are equipped with relevant competencies, skills and knowledge. Therefore, comprehensive training and education programmes are recommended to upskill the occupants’ knowledge and skills.

scholarly journals Webinar’s effect on nutritional knowledge to enhance immunity during COVID-19 pandemic

2022 ◽  
Vol 13 (1) ◽  
pp. 197-202
Author(s):  
Intan Permata Sari ◽  
Fauziah Adhima ◽  
Ghivari Zuhal Fahmi ◽  
Ramidha Syaharani ◽  
Widati Fatmaningrum
Keyword(s):  
Well Being ◽  
Posttest Score ◽  
Rank Test ◽  
Nutritional Knowledge ◽  
Adequate Nutrition ◽  
Significant Difference ◽  
Before And After ◽  
Post Test ◽  
Signed Rank Test ◽  
The Difference

Introduction: As of 31st December 2021, there have been 4,262,540 confirmed cases of COVID-19, including 144,088 death cases in Indonesia. COVID-19 pandemic has affected the nutrition aspect, as an increasing number of undernutrition children also increases risk of obesity. Our group conducts webinars with the purpose of increasing public knowledge and awareness regarding general well-being: importance of adequate nutrition to increase immunity in the COVID-19 pandemic. The purpose of the study is to examine webinar participants' knowledge before and after webinar. Method: The webinar conducted through a zoom meeting for 2 hours consists of 1 hour education and 1 hour question and answer session. The participants asked to fill a pretest before the webinar session and posttest after the webinar session. The results were statistically examined to determine the difference between pretest and posttest score. Results: The webinar participant’s demographic characteristics were dominated by 17-45 years old age group, high school graduates, and female participants. There is a significant difference (p<0.05) between pre and post-test score evaluated using Wilcoxon signed-rank test. After the webinar, there is a decreased number of participants with low-level nutritional knowledge from 31 to 23 participants. Conclusion: There is an increase in knowledge about the importance of adequate nutrition to increase immunity in the COVID-19 pandemic from pre and post-test data. Thus, this webinar contributes to providing knowledge to participants in supporting the strengthening of socialization of adequate nutrition during COVID-19 pandemic.

scholarly journals Gadofosveset-enhanced thoracic MR venography: a comparative study evaluating steady state imaging versus conventional first-pass time-resolved dynamic imaging

2017 ◽  
Vol 59 (4) ◽  
pp. 418-424 ◽  
Author(s):  
Teik C See ◽  
Andrew J Patterson ◽  
Nicholas J Hilliard ◽  
Ed Soh ◽  
Andrew P Winterbottom ◽  
...  
Keyword(s):  
Steady State ◽  
Image Quality ◽  
Blood Pool ◽  
Dynamic Imaging ◽  
Rank Test ◽  
Time Resolved ◽  
Significant Difference ◽  
First Pass ◽  
Signed Rank Test ◽  
The Difference

Background Dedicated blood-pool contrast agents combined with optimal angiographic protocols could improve the diagnostic accuracy of thoracic magnetic resonance angiography (MRA). Purpose To assess the clinical utility of Gadofesveset-enhanced imaging and compare an optimized steady-state (SS) sequence against conventional first-pass dynamic multi-phase (DMP) imaging. Material and Methods Twenty-nine patients (17 men, 12 women; mean age = 42.7, age range = 18–72 years) referred for MR thoracic venography were recruited. Imaging was performed on a 1.5T MRI system. A blood-pool contrast agent (Gadofesveset) was administered intravenously. Thirty temporal phases were acquired using DMP. This was immediately followed by a high-resolution SS sequence. Three radiologists in consensus reviewed seven thoracic vascular segments after randomizing the acquisition order. Image quality, stenoses, thromboses, and artifacts were graded using a categorical scoring system. The image quality for both approaches was compared using Wilcoxon’s signed-rank test. McNemar’s test was used to compare the proportions of stenosis grades, thrombus and artifacts. Results SS had significantly better image quality than DMP (3.14 ± 0.73 and 2.92 ± 0.60, respectively; P < 0.001). SS identified fewer stenoses (>50%) than DMP; the differences in stenosis categorizations was statistically significant ( P = 0.013). There was no significant difference in the proportions of vessels with thromboses ( P = 0.617). DMP produced more artifacts than SS (101 versus 85); however, the difference was not statistically significant ( P = 0.073). Conclusion Gadofesveset-enhanced thoracic angiography is clinically feasible. SS imaging produces better image quality and fewer artifacts than conventional DMP imaging.

Comparison of Single-Echo T2-weighted Fast Spin-Echo and Conventional Spin-Echo MR Sequences

1998 ◽  
Vol 11 (4) ◽  
pp. 471-476
Author(s):  
G. Sparacia ◽  
T. Angileri ◽  
A. Banco ◽  
R. Miraglia ◽  
N. Nicastro ◽  
...  
Keyword(s):  
Spin Echo ◽  
Fast Spin Echo ◽  
Rank Test ◽  
Significant Difference ◽  
Signed Rank Test ◽  
The Difference ◽  
Student’S T ◽  
Periventricular Lesions ◽  
Conventional Spin Echo ◽  
Fast Spin

We compared single-echo T2-weighted fast spin-echo (FSE) magnetic resonance imaging and conventional spin-echo (CSE) T2-weighted imaging in the detection of brain lesions of multiple sclerosis (MS). 16 patients with clinically definite MS underwent brain imaging at 0.5 T with T2-weighted single-echo fast spin-echo (FSE) and conventional spin-echo (CSE) sequences. Image analysis was performed by three of the investigators who worked together to reduce interobserver variability. Statistical analysis was performed using Student's t test to assess the difference in the contrast-to-noise (C/N) ratio of MS lesions between CSE and FSE sequences. The Wilcoxon signed rank test was used to evaluate the difference in the number of lesions between the two sequences. There was no significant difference in the overall total number of lesions detected on FSE vs CSE (964 vs 1009, P >.05). However significantly (P = .02) more posterior fossa lesions were detected using FSE than CSE, whereas significantly (P = .002) more periventricular lesions were detected using CSE than FSE. The difference in the number of lesions in the other sites was not significant (P > .05). There was no significant difference in the overall total C/N ratio of MS lesions between FSE and CSE sequences (11.7 ± 3.9 vs 12.6 ± 4). Considerable time savings can be made when substituting FSE for CSE sequences in T2-weighted imaging, and this is a compelling reason to employ such sequences in clinical practice. Our results suggest that for single-echo T2-weighted imaging, FSE can replace CSE in long term monitoring especially when patient movement prevents a useful investigation and when optional scanning planes are required.

PERBEDAAN FINANCIAL PERFORMANCE PASCA SECONDARY OFFERINGS

Wahana ◽  
2019 ◽  
Vol 22 (1) ◽  
pp. 41-49
Author(s):  
Djaja Perdana ◽  
Herbowo Herbowo
Keyword(s):  
Financial Performance ◽  
Stock Exchange ◽  
Hypothesis Test ◽  
Poor Performance ◽  
Rank Test ◽  
Growth Ratio ◽  
Significant Difference ◽  
Before And After ◽  
Signed Rank Test ◽  
Asset Turnover

This study aims to examine the differences in corporate financial performance before and after secondary offerings. The financial performance is proxied by WCR, DER, Solvency, ROA, ROE, Asset Turnover (ATO) and Growth ratio which representing the value of liquidity, financing, activity, performance and growth of the firm. The study involved 67 samples of the companies listed on the Indonesia Stock Exchange conducting secondary offerings during 2008-2013 period and selected through purposive random sampling method and using Financial Statement data from 2005-2016 period. Hypothesis test is performed using Wilcoxon Signed Rank test. The results of this study indicate that there is no significant difference in the ratio of Solvency, ROA and ROE between before and after secondary offerings, but there are significant differences in the ratio of WCR, DER, Asset Turnover and Growth. WCR ratio after secondary offerings increased, while DER ratio after secondary offerings decreased, the condition of both ratios showed better performance. While the indication of poor performance seen in decreasing asset turnover ratio and growth ratio.Keywords : agency theory, financial performance, secondary offerings

The Degree of Subjective Complaints of Students Practice in Mechanical Technology Laboratories

2018 ◽  
Vol 4 (1) ◽  
pp. 22
Author(s):  
I Ketut Widana
Keyword(s):  
Engineering Students ◽  
Standing Position ◽  
Statistical Test ◽  
Rank Test ◽  
Cross Sectional ◽  
Signed Rank ◽  
Before And After ◽  
Signed Rank Test ◽  
The Difference ◽  
Paired T Test

The working practice of the engineering students is part of the learning process that is irreducible and indispensable. The composition of  lecturing between theoretical and practical one is 40% to 60%. With this condition, the students spend more time at the laboratory. Generally, the students perform in the laboratory work by standing position. The design of research is observational cross-sectional. The method applied is observation, interview and measuring. The subjects of research are practicing students amounting to 21 students. Referring to the analysis of statistical test or Wilcoxon signed ranks test, the difference of effect of work position is significant, namely p < 0.05 towards musculoskeletal disorders (MSDs) before and after working. The quantity of the average complaint after working is score 44.62 ± 9.47. The result of Wilcoxon signed rank test shows that there is significant different effects of standing work position, namely p < 0.05 towards fatigue generally before and after working. The degree of the working pulse is on the average of 110.78  ± 17.80 bpm (beats per minutes) which can be categorized into the medium workload. Using paired t-test, the result is p < 0.05.

scholarly journals Cohort study of the overall survival of patients with pancreatic cancer in a hospital of specialties of Quito-Ecuador in the period 2007–2017

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Andrés Moreno Roca ◽  
Luciana Armijos Acurio ◽  
Ruth Jimbo Sotomayor ◽  
Carlos Céspedes Rivadeneira ◽  
Carlos Rosero Reyes ◽  
...  
Keyword(s):  
Pancreatic Cancer ◽  
Cohort Study ◽  
Survival Time ◽  
Univariate Analysis ◽  
Rank Test ◽  
Kaplan Meier ◽  
Significant Difference ◽  
Icd 10 ◽  
The Difference ◽  
Clinical Records

Abstract Objectives Pancreatic cancers in most patients in Ecuador are diagnosed at an advanced stage of the disease, which is associated with lower survival. To determine the characteristics and global survival of pancreatic cancer patients in a social security hospital in Ecuador between 2007 and 2017. Methods A retrospective cohort study and a survival analysis were performed using all the available data in the electronic clinical records of patients with a diagnosis of pancreatic cancer in a Hospital of Specialties of Quito-Ecuador between 2007 and 2017. The included patients were those coded according to the ICD 10 between C25.0 and C25.9. Our univariate analysis calculated frequencies, measures of central tendency and dispersion. Through the Kaplan-Meier method we estimated the median time of survival and analyzed the difference in survival time among the different categories of our included variables. These differences were shown through the log rank test. Results A total of 357 patients diagnosed with pancreatic cancer between 2007 and 2017 were included in the study. More than two-thirds (69.9%) of the patients were diagnosed in late stages of the disease. The median survival time for all patients was of 4 months (P25: 2, P75: 8). Conclusions The statistically significant difference of survival time between types of treatment is the most relevant finding in this study, when comparing to all other types of treatments.

Effect of needle type on plane block spread in a cadaveric porcine model

2021 ◽  
pp. bmjmilitary-2021-001827
Author(s):  
Scott Hughey ◽  
J Cole ◽  
G J Booth ◽  
R Gliniecki ◽  
E Stedjelarsen
Keyword(s):  
Plain Film ◽  
Perioperative Period ◽  
Transversus Abdominis ◽  
Tuohy Needle ◽  
Rank Test ◽  
Tap Block ◽  
Ultrasound Guided ◽  
Standard Block ◽  
Signed Rank Test ◽  
The Difference

IntroductionPlane blocks are an increasingly common type of regional anaesthesia technique in the perioperative period. Increased spread of local anaesthesia during plane blocks is thought to be related to an increased area of pain coverage. This study sought to assess differences in injectate spread comparing Tuohy needles with standard insulated stimulating block needles.Methods10 Yorkshire-Cross porcine cadavers were used in this study. Immediately following euthanasia, the cadavers underwent bilateral ultrasound-guided transversus abdominis plane (TAP) block injection with radiopaque contrast dye, with one side placed with a 20 g Tuohy needle, and the other side with a 20 g insulated stimulating block needle. Injectate spread was assessed using plain film X-ray and area of spread was measured to compare differences.ResultsAll 10 animals underwent successful ultrasound-guided TAP block placement. In all 10 animals, the area of contrast spread was greater with the Tuohy than stimulating needle. Wilcoxon signed-rank test was used to analyse the difference between the groups. The average difference between the two sides was 33.02% (p=0.002).ConclusionsThis is the first study to demonstrate differences in injectate spread with different needle types. This suggests enhanced spread with Tuohy needle compared with standard block needle, and may encourage its use during plane blocks.

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