scholarly journals Evaluation of Cracks in Metallic Material Using a Self-Organized Data-Driven Model of Acoustic Echo-Signal

2018 ◽  
Vol 9 (1) ◽  
pp. 95 ◽  
Author(s):  
Xudong Teng ◽  
Xin Zhang ◽  
Yuantao Fan ◽  
Dong Zhang
Keyword(s):  
Crack Growth ◽  
Statistical Significance ◽  
Distance Matrix ◽  
Strong Relationship ◽  
Data Driven ◽  
P Value ◽  
Probability Models ◽  
Statistical Parameters ◽  
Frequency Spectra ◽  
Statistical Probability

Non-linear acoustic technique is an attractive approach in evaluating early fatigue as well as cracks in material. However, its accuracy is greatly restricted by external non-linearities of ultra-sonic measurement systems. In this work, an acoustical data-driven deviation detection method, called the consensus self-organizing models (COSMO) based on statistical probability models, was introduced to study the evolution of localized crack growth. By using pitch-catch technique, frequency spectra of acoustic echoes collected from different locations of a specimen were compared, resulting in a Hellinger distance matrix to construct statistical parameters such as z-score, p-value and T-value. It is shown that statistical significance p-value of COSMO method has a strong relationship with the crack growth. Particularly, T-values, logarithm transformed p-value, increases proportionally with the growth of cracks, which thus can be applied to locate the position of cracks and monitor the deterioration of materials.

scholarly journals Estado nutricional e desfechos clínicos em pacientes críticos internados em hospital universitário

2020 ◽  
Vol 34 (4) ◽  
pp. 361-366
Author(s):  
Edcleide Oliveira dos Santos Olinto ◽  
Gina Araújo Martins Feitosa ◽  
Izaura Odir Lima Gomes da Costa ◽  
Janine Maciel Barbosa ◽  
Ericka Vilar Bôtto Targino ◽  
...  
Keyword(s):  
Body Mass ◽  
Statistical Significance ◽  
Strong Relationship ◽  
The Body ◽  
University Hospital ◽  
Nutritional Risk ◽  
World Health ◽  
P Value ◽  
Chi Square ◽  
Length Of Hospitalization

Introduction: There is a strong relationship between malnutrition and increased length of hospitalization and morbidity and mortality. Studies have shown that malnourished patients can have up to twenty times more complications than eutrophic ones. In critically ill patients, there is a tendency to catabolism, resulting in the loss of lean body mass, which when it reaches 40% is usually lethal. Methods: A quantitative, descriptive study was conducted on adults from both genders, admitted to the intensive care unit (ICU) of a university hospital, from March to December 2018. The following variables were collected from the evaluation and nutritional records: length of hospitalization in the ICU, date of discharge or death, nutritional risk through specific screening, height, weight and arm circumference (AC). For the screening, the Nutric score was used. For the nutritional evaluation, the body mass index (BMI) and AC indicators and the classifications recommended by the World Health Organization (2004) and Blackburn and Thornton (1979) were used. After collecting the data, they were analyzed in the Statistical Package for Social Sciences (SPSS) 13.0 and for the association of the variables the Chi-square test was used, considering statistical difference when the p value <0.05. Results: The sample consisted of 116 patients, mostly female (53.4%) whose median age was 46 years (interquartile range IQR 31-53). Regarding the frequency of nutritional risk, most patients (61.5%) had a low score. There was an important frequency of malnutrition, according to the AC indicator (73%), although BMI (43.5%) showed eutrophy. Even though most patients had low nutritional risk, those with high nutritional risk (38.5%) had a higher tendency to mortality, however, not statistically confirmed (p> 0.05). There was also a tendency of association between death and malnutrition, although no statistical significance was shown(p> 0.05). Conclusion: Patients at nutritional risk and/or malnutrition appear to be vulnerable to worse clinical outcomes.

scholarly journals Clustering for Data-driven Unraveling Artificial Neural Networks

2020 ◽  
Author(s):  
Felipe Farias ◽  
Teresa Ludermir ◽  
Carmelo Bastos-Filho
Keyword(s):  
Neural Networks ◽  
Statistical Significance ◽  
Feature Space ◽  
Data Driven ◽  
P Value ◽  
Proposed Model ◽  
Data Driven Approach ◽  
Benchmark Datasets ◽  
Hidden Layer ◽  
Fold Cross Validation

This work presents an investigation on how to define Neural Networks (NN) architectures adopting a data-driven approach using clustering to create sub-labels to facilitate the learning process and to discover the number of neurons needed to compose the layers. We also increase the depth of the model aiming to represent the samples better, the more in-depth it flows into the model. We hypothesize that the clustering process identifies sub-regions in the feature space in which the samples belonging to the same cluster have strong similarities. We used seven benchmark datasets to validate our hypothesis using 10-fold cross validation 3 times. The proposed model increased the performance, while never decreased it, with statistical significance considering the p-value $< 0.05$ in comparison with a Multi-Layer Perceptron with a single hidden layer with approximately the same number of parameters of the architectures found by our approach.

SERUM PROLACTINE LEVEL IN PATIENTS OF PSORIASIS VULGARIS AND ITS CORRELATION WITH DISEASE SEVERITY: A CASE-CONTROL STUDY

2019 ◽  
Vol 3 (6) ◽  
Author(s):  
Pawan Kumar Saini ◽  
Devendra Yadav ◽  
Rozy Badyal ◽  
Suresh Jain ◽  
Arti Singh ◽  
...  
Keyword(s):  
Disease Severity ◽  
Prolactin Level ◽  
Case Control Study ◽  
Statistical Significance ◽  
Case Control ◽  
Serum Prolactin ◽  
P Value ◽  
Serum Prolactin Level ◽  
R Value ◽  
Control Study

Background: Psoriasis is an autoimmune chronic inflammatory disorder affecting the skin mediated by T-lymphocytes resulting in production of cytokines which cause hyperproliferation of keratinocytes.  Several factors and hormones like Prolactin have an action similar to these cytokines in promoting the multiplication of keratinocytes and other cells like lymphocytes and epithelial cells may have a role on the etiopathogenesis of psoriasis. Aim:-The aim of study is to compare the serum Prolactin levels in patients of psoriasis with a control group. Setting and study design: This is a case-control study conducted in the department of Dermatology, Venereology and Leprosy GMC, Kota over a period of 1year from July 2017 to June 2018 Material and method: The study included 100 cases of psoriasis (60 males and 40 females) and 100 controls similar for age and sex. Serum Prolactin levels were measured by ECLIA and results were obtained. Statistical analysis: Mean and standard deviation were calculated for each variable. Statistical significance of the results was analyzed using correlation analysis (Pearson correlation coefficient) and independent samples t-test. Statistical significance was assumed at p value<0.05. Result: Serum Prolactin level was significantly higher in cases of psoriasis compared to controls (p-value <0.001). PASI score and serum Prolactin levels were found to have a positive correlation (r value = 0.337; p-value: 0.001). No significant  correlation was found between serum levels of Prolactin and duration of disease r value= -0.034, P value =0.733). Serum Prolactin level was higher in male patients compared to females patients. Conclusion:- High serum Prolactin may be a biological marker of disease severity in psoriasis and may have a role in the pathogenesis of psoriasis. Further studies with large sample size are required to confirm this hypothesis.

Awareness of radiation doses and risks among radiology residents, fellows, specialists, consultants and technologists in Jeddah, Saudi Arabia: Cross-Sectional Study. (Preprint)

2019 ◽  
Author(s):  
Bashayer Hassan Shuaib ◽  
Rahaf Hisham Niazi ◽  
Ahmed Haitham Abduljabbar ◽  
Mohammed Abdulraheem Wazzan
Keyword(s):  
Interventional Radiology ◽  
Ionizing Radiation ◽  
Statistical Significance ◽  
Knowledge Score ◽  
P Value ◽  
Radiation Doses ◽  
Cross Sectional ◽  
The Right ◽  
Interventional Radiology Procedures ◽  
Radiology Staff

BACKGROUND Radiology now plays a major role to diagnose, monitoring, and management of several diseases; numerous diagnostic and interventional radiology procedures involve exposure to ionizing radiation. Radiology now plays a major role to diagnose, monitoring, and management of several diseases; numerous diagnostic and interventional radiology procedures involve exposure to ionizing radiation. OBJECTIVE This study aimed to discover and compare the awareness level of radiation doses, protection issues, and risks among radiology staff in Jeddah hospitals. METHODS A cross-sectional survey containing 25 questions on personal information and various aspects of radiation exposure doses and risks was designed using an online survey tool and the link was emailed to all radiology staff in eight tertiary hospitals in Jeddah. The authors were excluded from the study. A P-value of < .05 was used to identify statistical significance. All analyses were performed using SPSS, version 21. RESULTS Out of 156 participants the majority 151 (96.8%) had poor knowledge score, where the mean scores were 2.4±1.3 for doses knowledge, 2.1±1.1for cancer risks knowledge, 2.3±0.6 for general information, and 6.7±1.9 for the total score. Only 34.6% of the participants were aware of the dosage of a single-view chest x-ray, and 9.0% chose the right answer for the approximate effective dose received by a patient in a two-view. 42.9% were able to know the correct dose of CT abdomen single phase. There is a significant underestimation of cancer risk of CT studies especially for CT abdomen where only 23.7% knew the right risk. A p-value of <0.05 was used to identify statistical significance. No significant difference of knowledge score was detected regarding gender (P =.2) or work position (P=.66). CONCLUSIONS Our survey results show considerable inadequate knowledge in all groups without exception. We recommended a conscientious effort to deliver more solid education and obtain more knowledge in these matters and providing periodic training courses to teach how to minimize the dose of radiation and to avoid risk related. CLINICALTRIAL not applicable

scholarly journals Can diffusion and T2 star-weighted magnetic resonance imaging aid in the diagnosis of ectopic endometrium?

2021 ◽  
Vol 52 (1) ◽  
Author(s):  
Mariam Raafat ◽  
Soha H. Talaat ◽  
Salma M. Abdelghaffar ◽  
Engy A. Ali
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Statistical Significance ◽  
P Value ◽  
Large Sample Size ◽  
Resonance Imaging ◽  
Conventional Mri ◽  
Patient Will ◽  
Magnetic Resonance Imaging Mri ◽  
Ectopic Endometrium

Abstract Background Endometriosis is a common gynecologic disorder characterized by the implantation of the endometrial tissue ectopically outside the endometrial cavity. It affects about 10% of females at the childbearing period and is estimated to be present up to 20–50% in women complaining of infertility. While laparoscopy is considered the mainstay for diagnosis, magnetic resonance imaging (MRI) is recognized as a useful tool for definitive diagnosis, pre-surgical planning, and determining whether the patient will require multi-specialty involvement. The aim of this study is to evaluate the performance of MRI with the addition of diffusion-weighted imaging (DWI) and T2 star (T2*) to conventional MRI, for the accurate assessment of ectopic endometrium. Results Endometriotic lesions that showed diffusion restriction on DWI were 80.7%, and 96.1% of the endometriotic lesions had signal voids on the T2*W sequence, whereas only 65.4% of the lesions had typical signal intensities on T1WI and T2WI. Diagnostic performance of the MRI examination was improved by the use of the diffusion sequence and better improved by the T2* sequence, compared to the conventional MR protocol sensitivity (SE) = 96.12% and specificity (SP) = 85.7% in T2*-weighted images, SE = 80.7% and SP = 71.4% in DWI, and SE = 65.4% and SP = 71.4% in conventional MRI. P value for conventional MRI was 0.1, which is of no statistical significance (p < 0.05). P value for DWI was 0.016, which is statistically significant (p < 0.05). P value for T2*WI was 0.001, which is more statistically significant (p < 0.05) and could be adequately correlated with laparoscopy. Conclusion DWI and T2* significantly increase MRI diagnostic accuracy by allowing the detection of the hemorrhagic character of the endometriotic lesions. Studies with a large sample size are needed to confirm that they can replace invasive laparoscopy for the diagnosis of endometriosis.

Thromboelastography (TEG) results are predictive of ischemic and hemorrhagic complications in patients with unruptured intracranial aneurysms treated with flow diversion

2021 ◽  
pp. 159101992110259
Author(s):  
Kainaat Javed ◽  
Santiago R Unda ◽  
Ryan Holland ◽  
Adisson Fortunel ◽  
Rose Fluss ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Intracranial Aneurysms ◽  
Statistical Significance ◽  
Alpha Angle ◽  
Flow Diversion ◽  
P Value ◽  
Hemorrhagic Complication ◽  
Unruptured Intracranial Aneurysms ◽  
Hemorrhagic Complications ◽  
Groin Hematoma

Introduction Flow diversion is an effective treatment modality for intracranial aneurysms but is associated with ischemic and hemorrhagic complications. Patients treated with flow diversion require dual antiplatelet therapy and subsequent platelet function tests. At our institution, Thromboelastography with Platelet Mapping (TEG-PM) is the test of choice. The primary objective of this study was to identify TEG parameters that are predictive of postoperative complications in patients treated with elective flow diversion. Methods This was a retrospective study of 118 patients with unruptured intracranial aneurysms treated with flow diversion. Data was collected via chart review. Bivariate analyses were performed to identify significant variables in patients who suffered an ischemic stroke or a groin hematoma. ROC curves were constructed for the TEG parameters with statistical significance. Bivariate analyses were repeated using dichotomized TEG results. Results Patients who experienced a symptomatic ischemic stroke had a history of stroke (p value = 0.007), larger aneurysm neck width (p value = 0.017), and a higher alpha angle (p value = 0.013). Cut off point for ischemic complication is 63° on ROC curve with a sensitivity of 100% and specificity of 65%. Patients who experienced a groin hematoma were no different from their healthy peers but had a lower alpha angle (p value = 0.033). Cut off point for hemorrhagic complication is 53.3° with a sensitivity of 82% and specificity of 67%. Conclusion The Alpha Angle parameter of TEG-PM has a sizeable predictive ability for both ischemic complications of the central nervous system and hemorrhagic complications of the access site after elective flow diversion.

scholarly journals Social determinants of telemedicine utilization in ambulatory cardiovascular patients during the COVID-19 pandemic

2021 ◽  
Author(s):  
Kemar J Brown ◽  
Njambi Mathenge ◽  
Daniela Crousillat ◽  
Jaclyn Pagliaro ◽  
Connor Grady ◽  
...  
Keyword(s):  
Statistical Significance ◽  
The Elderly ◽  
P Value ◽  
Chi Square ◽  
Cardiovascular Patients ◽  
Baseline Characteristics ◽  
Racial Ethnic ◽  
Cardiovascular Care ◽  
Zip Code ◽  
Hispanic White

Abstract Background The coronavirus disease 2019 (COVID-19) pandemic has resulted in the rapid uptake of telemedicine (TM) for routine cardiovascular care. Objectives To examine the predictors of TM utilization among ambulatory cardiology patients during the COVID-19 pandemic. Methods In this single centre retrospective study, all ambulatory cardiovascular encounters occurring between March 16th - June 19th, 2020 were assessed. Baseline characteristics by visit type (in-person, TM-phone, TM-video) were compared using Chi-square and student t-tests, with statistical significance defined by p value &lt; 0.05. Multivariate logistic regression was used to explore the predictors of TM versus in-person care. Results 8446 patients (86% Non-Hispanic White, 42% female, median age 66.8 +/- 15.2 years) completed an ambulatory cardiovascular visit during the study period. TM-phone (n = 4,981, 61.5%) was the primary mode of ambulatory care followed by TM-video (n = 2693, 33.2%). Non-Hispanic Black race (OR 0.56; 95% CI: 0.35 - 0.94, p-value=0.02), Hispanic ethnicity (OR 0.53; 95% CI: 0.29 - 0.98, p = 0.04), public insurance (Medicaid OR 0.50; 95% CI:0.32 – 0.79, p = 0.003, Medicare OR 0.65; 95% CI: 0.47– 0.89, p = 0.009), zip-code linked median household income (MHI) of &lt;$75,000, age &gt;85 years, and patients with a diagnosis of heart failure were associated with reduced access to TM-video encounters and a higher likelihood of in-person care. Conclusions Significant disparities in TM-video access for ambulatory cardiovascular care exist among the elderly, lower income, as well as Black and Hispanic racial/ethnic groups.

The Role of Doppler Ultrasound, CT Angiography, and Conventional Angiography in Detection of Peripheral Arterial Disease

2021 ◽  
pp. 154431672110303
Author(s):  
Sayan Sarkar ◽  
Shyam Mohan ◽  
Shakthi Parvathy
Keyword(s):  
Computed Tomography ◽  
Peripheral Arterial Disease ◽  
Ct Angiography ◽  
Doppler Ultrasound ◽  
Predictive Value ◽  
Color Doppler ◽  
Statistical Significance ◽  
Arterial Disease ◽  
P Value ◽  
Peripheral Arterial

The purpose of this study is to analyze how accurate duplex ultrasonography using color Doppler and computed tomography (CT) angiography are in detection of peripheral arterial disease (PAD) in comparison with the Gold Standard of digital subtraction angiography (DSA). This is a single-center prospective, analytical study done on patients with symptoms of PAD referred to the Department of Radiodiagnosis of Medical Trust Hospital (n = 53). All patients were imaged with color Doppler, CT angiography, and DSA. The peak systolic velocity (PSV) ratio was calculated by Doppler ultrasound, and the percentage stenosis for the same vascular segments was calculated using CT angiography and DSA. To test the statistical significance between the results, chi-square test was used. A P value <.05 indicates statistical significance. The PSV ratio for each grade—normal (<1.5), mild (1.5-2.8), moderate (2.9-4.9), and severe (≥5)—and the percentage of stenosis for each grade observed on CT angiography—normal (<20% stenosis), mild (20%-49% stenosis), moderate (50%-74% stenosis), severe (75%-99% stenosis), and total occlusion (100% stenosis)—were found to be highly sensitive and specific with good positive predictive value, negative predictive value, and accuracy level when compared with DSA with narrow confidence intervals for each range. The P value was <.001 for both color Doppler and CT angiography. Computed tomography angiography can be an effective tool as an alternative to DSA for gradation of stenosis if the artifacts resulting from vascular calcification can be avoided. Duplex ultrasonography can be utilized for gradation of stenosis by using the value of PSV ratio and spectral pattern together. However, it can only act as an adjunct to CT angiography because it is incapable of imaging the full length of the arterial segments in 1 frame.

scholarly journals Assessment of Immunological Features in Muscle-Invasive Bladder Cancer Prognosis Using Ensemble Learning

Cancers ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1624
Author(s):  
Christos G. Gavriel ◽  
Neofytos Dimitriou ◽  
Nicolas Brieu ◽  
Ines P. Nearchou ◽  
Ognjen Arandjelović ◽  
...  
Keyword(s):  
Bladder Cancer ◽  
Statistical Significance ◽  
Tnm Staging ◽  
Cancer Prognosis ◽  
Clinical Staging ◽  
Invasive Bladder Cancer ◽  
P Value ◽  
Muscle Invasive Bladder Cancer ◽  
Tissue Samples ◽  
Muscle Invasive

The clinical staging and prognosis of muscle-invasive bladder cancer (MIBC) routinely includes the assessment of patient tissue samples by a pathologist. Recent studies corroborate the importance of image analysis in identifying and quantifying immunological markers from tissue samples that can provide further insight into patient prognosis. In this paper, we apply multiplex immunofluorescence to MIBC tissue sections to capture whole-slide images and quantify potential prognostic markers related to lymphocytes, macrophages, tumour buds, and PD-L1. We propose a machine-learning-based approach for the prediction of 5 year prognosis with different combinations of image, clinical, and spatial features. An ensemble model comprising several functionally different models successfully stratifies MIBC patients into two risk groups with high statistical significance (p value < 1×10−5). Critical to improving MIBC survival rates, our method correctly classifies 71.4% of the patients who succumb to MIBC, which is significantly more than the 28.6% of the current clinical gold standard, the TNM staging system.

Comparative assessment of overweight/obesity among rural and urban reproductive-age women in Ethiopia: Evidence from a cross-sectional 2016 national survey

2021 ◽  
pp. 026010602098234
Author(s):  
Gizachew Worku Dagnew ◽  
Melash Belachew Asresie
Keyword(s):  
Family Size ◽  
Health Problem ◽  
Rural Women ◽  
Alcohol Intake ◽  
Statistical Significance ◽  
Public Health Problem ◽  
Reproductive Age ◽  
P Value ◽  
Cross Sectional ◽  
Reproductive Age Women

Background: Overweight/obesity has become a global health problem for both developed and developing regions. Nowadays, overweight/obesity among childrearing-age women has become rapidly increasing in both urban and rural areas. Aim: This study aimed to assess the variation of overweight/obesity among urban and rural reproductive-age women in Ethiopia. Methods: For this study, the 2016 Ethiopia Demographic and Health Survey data were used. The survey was a community-based cross-sectional study, which used a two-stage stratified cluster sampling technique to select the participants. A total of 13,451 reproductive-age women were included in the analysis. Both descriptive and analytical analysis was performed. A p-value of less than 0.05 was used as the measure of statistical significance. Results: The prevalence of overweight/obesity among urban reproductive-age women was statistically higher ( p = 21.5%; 95% confidence interval (CI): 18.2–25.1) than the rural women ( p = 3.5%; 95% CI: 2.9%–4.2%). Women who attend secondary or above education, women in the age groups 25–34 and ≥ 35 years, and high wealth index (rich) had higher odds of overweight/obesity in both urban and rural women. Moreover, women who were married, who had a large family size, and who have a history of alcohol intake had higher odds of overweight/obesity among urban women. Conclusions: Overweight/obesity among reproductive-age women is a public health problem in Ethiopia, especially for women who are living in urban settings. Therefore, it is important to establish targeted overweight reduction programs with particular emphasis on urban, older aged, educated, and married women. Additionally, encouraging the limitation of the number of family size and alcohol intake can reduce women’s overweight/obesity.

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