scholarly journals A Probabilistic Model For Co-Occurrence Analysis in Bibliometrics

2021 ◽  
Author(s):  
Xiaobei Zhou ◽  
Miao Zhou ◽  
Desheng Huang ◽  
Lei Cui
Keyword(s):  
Probabilistic Model ◽  
Statistical Significance ◽  
Low Frequency ◽  
Critical Threshold ◽  
P Value ◽  
Model Framework ◽  
Practical Applications ◽  
Mesh Terms ◽  
Occurrence Matrix ◽  
Selection Of

Abstract The co-occurrence analysis of Medical Subject Heading (MeSH) terms in the bibliographic database is popularly used in bibliometrics. Practically for making the result interpretable, it is necessary to apply a certain filter procedure of co-occurrence matrix for removing the low-frequency items that should not appear in the final result due to their low representativeness for co-occurrence analysis. Unfortunately, there is rare research referring to determine a critical threshold to remove noise of data for co-occurrence analysis. Here, we propose a probabilistic model for co-occurrence analysis that can calculate statistical significance (p-values) of co-occurred items. With help of this model, the dimensionality of co-occurrence network could be conveniently reduced according to selection of different levels of p-value thresholds. The conceptual model framework, simulation and practical applications are illustrated in the manuscript. Further details (including all reproducible codes) can be downloaded from the project website: https://github.com/Miao-zhou/Co-occurrence-analysis.git.

scholarly journals Improving Customers Satisfaction through Significance of Technical Attribute in QFD Studies

2021 ◽  
Vol 7 (2) ◽  
Author(s):  
Zafar Iqbal ◽  
Lubna Waheed ◽  
Waheed Muhammad ◽  
Rajab Muhammad
Keyword(s):  
Quality Function Deployment ◽  
Statistical Significance ◽  
P Value ◽  
Relationship Matrix ◽  
The Novel ◽  
Test Statistic ◽  
P Values ◽  
Weighted Matrix ◽  
Importance Ratings ◽  
Selection Of

Purpose: Quality Function Deployment, (QFD) is a methodology which helps to satisfy customer requirements through the selection of appropriate Technical Attributes (TAs). The rationale of this article is to provide a method lending statistical support to the selection of TAs.  The purpose is to determine the statistical significance of TAs through the derivation of associated significance (P) values.   Design/Methodology/Approach: We demonstrate our methodology with reference to an original QFD case study aimed at improving the educational system in high schools in Pakistan; and then with five further published case studies obtained from literature. Mean weights of TAs are determined. Considering each TA mean weight to be a Test Statistic, a weighted matrix is generated from the VOCs’ importance ratings, and ratings in the relationship matrix. Finally using R, P-values for the means of original TAs are determined from the hypothetical population of means of TAs.  Findings: Each TA’s P-value evaluates its significance/insignificance in terms of distance from the grand mean. P-values indirectly set the prioritization of TAs. Implications/Originality/Value: The novel aspect of this study is extension of mean weights of TAs, to also provide P-values for TAs. TAs with significant importance can be resolved on priority basis, while other can be fixed with appropriateness.

Importance of Temperament in Individualized Homeopathic Prescription: Evaluation by an Open, Randomized, Pilot Trial

Homeopathy ◽  
2019 ◽  
Vol 108 (04) ◽  
pp. 240-247
Author(s):  
Najne Sultana ◽  
Amitava Samanta ◽  
Munmun Koley ◽  
Subhranil Saha
Keyword(s):  
Chronic Diseases ◽  
Statistical Significance ◽  
Pilot Trial ◽  
Mean Difference ◽  
Group Differences ◽  
Health Improvement ◽  
P Value ◽  
Analog Scale ◽  
Self Rated Health ◽  
Selection Of

Background The importance of temperament in the selection of an individualized homeopathic medicine has not been evaluated systematically. The current study explored this under-researched area. Materials and Methods A prospective, open, randomized (1:1), two parallel arms, pilot trial was performed on patients suffering from various chronic diseases. Each patient's temperament was assessed using a newly developed “temperament diagnostic questionnaire”. Outcome measures were health status using the EQ-5D-5L questionnaire and a visual analog scale (VAS) of patient's self-rated health, measured at baseline and at 3 months. Homeopathic medicines were prescribed on the basis of individualization, randomly with or without accounting for individual temperament, and patients grouped accordingly (temperament(+) and temperament(−)). Baseline comparability of the two groups was checked, followed by analysis of group differences. A p-value < 0.01 was considered as statistically significant. Results Fifty protocol-compliant patients were analyzed. The two groups were comparable at baseline. Over 3 months of intervention, there was significant improvement (p < 0.01) in each group. Though improvement in the EQ-5D-5L score was greater in the temperament(+) group (mean difference, 2.4; 95% confidence interval [CI], 0.2 to 4.5), the change did not achieve the threshold for statistical significance (p = 0.029). Improvement in VAS score was significantly greater in the temperament(+) group than in temperament(–) patients (mean difference, 15.2; 95% CI, 4.9 to 25.4; p = 0.004). Conclusion Considering temperament as a key element of individualized prescription may enhance health improvement from homeopathic treatment in chronic diseases. Independently replicated rigorous trials with validated scales are warranted. Trial Registration CTRI/2018/03/012433.

A Parametric Amplifier for Weak, Low-Frequency Forces

2015 ◽  
Author(s):  
Amit Dolev ◽  
Izhak Bucher
Keyword(s):  
Multiple Scales ◽  
Low Frequency ◽  
Parametric Amplifier ◽  
Noise Levels ◽  
Signal To Noise ◽  
External Excitation ◽  
Practical Applications ◽  
Analytic Expressions ◽  
Frequency Excitation ◽  
Selection Of

The present work introduces a tunable parametric amplifier (PA) with a hardening, Duffing-type nonlinearity. By introducing a multi-frequency parametric excitation, one is able to achieve both: (i) High amplification of the weak, low-frequency external excitation (ii) Projection of the low frequency on any natural frequency of the system, thus transforming the low frequency excitation to a frequency band where signal levels are considerably higher. Having developed multiple-scales based expressions for the response of such systems, it is demonstrated that (a) The analytical analysis agrees well with numerically obtained simulations. (b) Both the phase, magnitude and spatial projection of this force on any system’s eigenvector can be retrieved by appropriate selection of parameters, with superior signal to noise levels. Closed form analytic expressions for the sensitivity and gain are derived and analyzed. Additionally, some practical applications envisaged for the proposed method will be outlined.

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 Tetracycline-Resistant Bacteria Selected from Water and Zebrafish after Antibiotic Exposure

2021 ◽  
Vol 18 (6) ◽  
pp. 3218
Author(s):  
Ana Rita Almeida ◽  
Marta Tacão ◽  
Joana Soares ◽  
Inês Domingues ◽  
Isabel Henriques
Keyword(s):  
Statistical Significance ◽  
Recovery Period ◽  
Antibiotic Resistance Genes ◽  
Antibiotic Use ◽  
Resistant Bacteria ◽  
Antibiotic Resistant ◽  
Potential Impact ◽  
Susceptibility Profiles ◽  
Selection Of ◽  
Significant Mortality

The emergence of antibiotic-resistant pathogens due to worldwide antibiotic use is raising concern in several settings, including aquaculture. In this work, the selection of antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARGs) was evaluated after exposure of zebrafish to oxytetracycline (OTC) for two months, followed by a recovery period. The selection of ARB in water and fish was determined using selective media. The abundance of tetA genes was estimated through qPCR. Higher prevalence of ARB was measured in all samples exposed to the antibiotic when compared to control samples, although statistical significance was only achieved five days after exposure. Isolates recovered from samples exposed to the antibiotic were affiliated with Pseudomonas and Stenotrophomonas. Various antibiotic susceptibility profiles were detected and 37% of the isolates displayed multidrug resistance (MDR). The selection of the tetA gene was confirmed by qPCR at the highest OTC concentration tested. Two MDR isolates, tested using zebrafish embryos, caused significant mortality, indicating a potential impact on fish health and survival. Overall, our work highlights the potential impact of antibiotic contamination in the selection of potential pathogenic ARB and ARGS.

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.

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