bluuebunny/crossref_metadata_2025_split huggingface dataset:
COVID-19 in Egypt after a year: the first and second pandemic waves from the radiological point of view; multi-center comparative study on 2000 patients
Authors: Samir Ahmed , Elabd Amr Magdy , Mohamed Walid , Baess Ayman Ibrahim , Sweed Rania Ahmed , Abdelgawad Mohamed Saied 
Published: July 2021

Abstract
Background
One year has passed since the announcement of COVID-19 as a pandemic and two waves had already stricken Egypt. The authors witnessed several atypical radiological features through the second pandemic wave, either early at the active infective stage or delayed at the post-infectious convalescent period. They believed every radiologist should be familiar with these features. Therefore, they performed this comparative study on 2000 Egyptian patients using multi-slice computed tomography (MSCT) to highlight the radiological differences between the first and second pandemic waves and correlate them to the clinical status.

Results
This random multi-center comparative study was retrospectively conducted on 2000 COVID-19 Egyptian patients; 1000 patients were registered at the first pandemic wave from April 2020 till September 2020, while the other 1000 patients were registered at the second pandemic wave from October 2020 till March 2020. Follow up CT examinations were performed for 49 and 122 patients through the first and second pandemic waves respectively. MSCT examinations were carefully evaluated by four expert consulting radiologists who came to a consensus. Meanwhile, the correlation with the clinical outcome was performed by two consulting pulmonologists. During the second pandemic wave, the prevalence rate of the “crazy-paving” pattern had significantly increased by 1.3 times (P value = 0.002). Additionally, the prevalence rate of the “air-bubble” sign had significantly increased by 1.9 times (P value = 0.02). Similarly, the presence of enlarged mediastinal lymph nodes (> 1 cm in short-axis diameter) had significantly increased by 1.7 times (P value = 0.036). Furthermore, the prevalence rate of pericardial effusion had significantly increased by 2.5 times (P value = 0.003). The above-mentioned signs were correlated to increased clinical severity and higher rates of hospitalization. Unexpectedly, other atypical radiological signs were only encountered through the second pandemic wave, including bronchiectatic changes (2.5%), “head-cheese” pattern (0.8%), cavitation (0.5%), and “bulls-eye” sign (0.2%). The prevalence rate of post-COVID fibrosis had doubled through the second wave but not in a significant way (P value = 0.234). Secondary fungal infection was only encountered throughout the second pandemic wave in four patients. COVID-19 reinfection was encountered in a single patient only during the second pandemic wave.

Conclusion
After 1 year from the announcement of COVID-19 as a pandemic, the radiological presentation of COVID-19 patients showed some significant differences between its first and second waves.
Roles of mortar volume in porosity, permeability and strength of pervious concrete
Authors: Li Leo Gu , Feng Jia-Jian , Xiao Bo-Feng , Chu Shao-Hua , Kwan Albert Kwok Hung 
Published: July 2021

AbstractPervious concrete is designed to be porous to allow permeation of water and air for combating the environmental and drainage problems arising from urbanization. However, despite extensive research, it is still not clear how best to design pervious concrete mixes to achieve good concurrent permeability-strength performance. In a previous study, the authors found that there is a necessity to distinguish between interconnected porosity and open porosity, and between unsubmerged permeability and submerged permeability. In this study, based on the thinking that fine aggregate may be added to reduce the paste volume provided the fine aggregate is fine enough to form a coherent mass with the paste, further research was conducted to develop the mortar type pervious concrete with reduced paste volume and investigate the roles of the mortar volume in porosity, permeability and strength. A new series of concrete mixes with varying mortar volume were tested and the results revealed that the interconnected porosity is the major factor determining the permeability while the open porosity and water/cement ratio are the major factors determining the strength. More importantly, the mortar volume plays a key role in each performance attribute.
Application of SeDeM Expert System in the development of novel directly compressible co-processed excipients via co-processing
Authors: Salim Ilyasu , Olowosulu Adeniji Kehinde , Abdulsamad Abdulrahman , Gwarzo Mahmud Sani , Khalid Garba Mohammed , Ahmad Naimatu Tijjani , Eichie Florence Egbomonjiade , Kurfi Fatima Shuaibu 
Published: July 2021

Abstract
Background
Computer-aided formulation design is gaining fantastic attention in chemical engineering of high functionality pharmaceutical materials for dosage form manufacture. To accelerate development of novel formulations in a quality-by-design perspective, SeDeM Expert System preformulation algorithm was developed as a tool for the design of solid drug delivery systems and for prediction of direct compression manufacturability of solid formulations. This research aims to integrate SeDeM Expert System into particle engineering design space of co-processing of solid excipients to develop novel composites with optimum direct compression propensity, using corn starch and microcrystalline cellulose powders as model primary excipients.

Result
The data and information generated from the expert system have elucidated the bulk-level characteristics of the primary excipients, enabled computation of the optimum co-processing ratio of the ingredients, and validated the impact of co-processing on material functionality. The experimental flowability (7.78±0.17), compressibility functions (5.16±0.14), parameter profile (0.92), and parametric profile index (6.72±0.27) of the engineered composites, were within the acceptable thresholds. With a reliability constant of 0.961, the net direct compression propensity of the composites expressed as Good Compression Index (6.46±0.26) was superior to that of the primary excipients, but comparable to reference co-processed materials, StarLac® (6.44±0.14) and MicroceLac®100 (6.58±0.03).

Conclusion
Application of SeDeM Expert System in particle engineering via co-processing has provided an accelerated upstream proactive mechanism for designing directly compressible co-processed excipients in a quality-by-design fashion. A four-stage systematic methodology of co-processing of solid excipients was postulated. Stage I entails the characterization of CMAs of both defective and corrective excipients, and elucidation of their physicomechanical limitations using SeDeM diagrams. Stage II involves computation of loading capacity of the corrective excipient using dilution potential equation. Stage III entails the selection of co-processing technique based on desired Critical Material Attributes as revealed by the information obtained from Stage I. Stage IV evaluates the impact of co-processing by monitoring the critical behavior of the engineered composites with a decision on either to accept or reject the product.
The Motherhood Penalty in Context: Assessing Discrimination in a Polarized Labor Market
Authors: Ishizuka Patrick 
Published: July 2021

Abstract
Prior research provides important insights into employer discrimination against mothers but has focused exclusively on college-educated mothers in professional and managerial occupations. As a result, we lack evidence about whether less-educated mothers navigating the low-wage labor market experience similar disadvantages and whether the mechanisms underlying discrimination vary across contexts. These gaps are important because more- and less-educated mothers increasingly possess distinct resources and face unique demands both at home and at work, which may impact employer perceptions of conflicts between motherhood and job performance. This study reports results from an original field experiment in which 2,210 fictitious applications were submitted to low-wage service and professional/managerial job openings across six U.S. cities, experimentally manipulating signals of motherhood status. Findings provide causal evidence that employers in both contexts discriminate against mothers relative to equally qualified childless women. However, within labor market segments, distinct job demands listed in job advertisements are associated with stronger discrimination: time pressure, collaboration, and travel in professional/managerial jobs and schedule instability in low-wage service jobs. These findings have important implications for our understanding of the mechanisms underlying mothers' disadvantages in an increasingly polarized labor market.
MRI accuracy and interobserver agreement in locally advanced cervix carcinoma
Authors: Jacquot Amalia , Chauleur Céline , Russel-Robillard Anne-Sophie , Tinquaut Fabien , Sotton Sandrine , Magne Nicolas , Etievent Guillaume 
Published: July 2021

Objectives:
The main standard of care for locally advanced cervix carcinoma (LACC) is radiochemotherapy (RCT) followed by brachytherapy. A surgical approach may still be discussed based on pelvic MRI-derived residual tumour evaluation. As no interobserver agreement study has ever been conducted to our knowledge, the aim of the present study was to report on pelvic MRI accuracy and interobserver agreement in LACC.

Methods:
We carried out a retrospective study in a French university hospital. Medical records of all consecutive patients treated with curative intent for LACC by RCT followed by brachytherapy and completion pelvic surgery between January 2014 and January 2020 were reviewed. Local response was assessed through pelvis MRI and histological analysis after completion surgery. MRI data were independently evaluated by two radiologists with varying experience. The two main interobserving criteria we used were complete response and residual tumour.

Results:
23 patients fulfilled the inclusion criteria. Agreement between the junior and senior radiologist was moderate to strong. Indeed, regarding main criteria, κ was 0.65 for complete response and 0.57 for residual tumour. Interestingly, the present study shows a lower sensitivity whatever the radiologists than in the international literature.

Conclusion:
The present study highlights a low interobserver variability regarding pelvic MRI in the assessment of RCT followed by brachytherapy in LACC. Yet, sensitivity was lower than in literature.

Advances in knowledge:
Radiology is part of treatment decision-making, the issue of heterogeneity regarding radiologists’ training and experience to cancer (sensitivity and specificity) turns essential, so does MRI accuracy.
Prostate MRI quality: a critical review of the last 5 years and the role of the PI-QUAL score
Authors: Giganti Francesco , Kasivisvanathan Veeru , Kirkham Alex , Punwani Shonit , Emberton Mark , Moore Caroline M , Allen Clare 
Published: July 2021

There is increasing interest in the use of multiparametric magnetic resonance imaging (mpMRI) in the prostate cancer pathway. The European Association of Urology (EAU) and the British Association of Urological Surgeons (BAUS) now advise mpMRI prior to biopsy, and the Prostate Imaging Reporting and Data System (PI-RADS) recommendations set out the minimal technical requirements for the acquisition of mpMRI of the prostate.
The widespread and swift adoption of this technique has led to variability in image quality. Suboptimal image acquisition reduces the sensitivity and specificity of mpMRI for the detection and staging of clinically significant prostate cancer.
This critical review outlines the studies aimed at improving prostate MR quality that have been published over the last 5 years. These span from the use of specific MR sequences, magnets and coils to patient preparation. The rates of adherence of prostate mpMRI to technical standards in different cohorts across the world are also discussed.
Finally, we discuss the first standardised scoring system (i.e., Prostate Imaging Quality, PI-QUAL) that has been created to evaluate image quality, although further iterations of this score are expected in the future.
A prediction model for degree of differentiation for resectable locally advanced esophageal squamous cell carcinoma based on CT images using radiomics and machine-learning
Authors: Kawahara Daisuke , Murakami Yuji , Tani Shigeyuki , Nagata Yasushi 
Published: July 2021

Objective: To propose the prediction model for degree of differentiation for locally advanced esophageal cancer patients from the planning CT image by radiomics analysis with machine learning. Methods: Data of 104 patients with esophagus cancer, who underwent chemoradiotherapy followed by surgery at the Hiroshima University hospital from 2003 to 2016 were analyzed. The treatment outcomes of these tumors were known prior to the study. The data were split into 3 sets: 57/16 tumors for the training/validation and 31 tumors for model testing. The degree of differentiation of squamous cell carcinoma was classified into two groups. The first group (Group I) was a poorly differentiated (POR) patients. The second group (Group II) was well and moderately differentiated patients. The radiomics feature was extracted in the tumor and around the tumor regions. A total number of 3480 radiomics features per patient image were extracted from radiotherapy planning CT scan. Models were built with the least absolute shrinkage and selection operator (LASSO) logistic regression and applied to the set of candidate predictors. The radiomics features were used for the input data in the machine learning. To build predictive models with radiomics features, neural network classifiers was used. The precision, accuracy, sensitivity by generating confusion matrices, the area under the curve (AUC) of receiver operating characteristic curve were evaluated. Results: By the LASSO analysis of the training data, we found 13 radiomics features from CT images for the classification. The accuracy of the prediction model was highest for using only CT radiomics features. The accuracy, specificity, and sensitivity of the predictive model were 85.4%, 88.6%, 80.0%, and the AUC was 0.92. Conclusion: The proposed predictive model showed high accuracy for the classification of the degree of the differentiation of esophagus cancer. Because of the good prediction ability of the method, the method may contribute to reducing the pathological examination by biopsy and predicting the local control. Advances in knowledge: For esophageal cancer, the differentiation of degree is the import indexes reflecting the aggressiveness. The current study proposed the prediction model for the differentiation of degree with radiomics analysis.
Radiation in orthopaedics (RIO) study: a national survey of UK orthopaedic surgeons
Authors: Raza Mohsen , Geleit Ryan , Houston James , Williams Rachel , Trompeter Alex 
Published: July 2021

Objectives:
Orthopaedic surgeons have a responsibility to minimise risks of ionising radiation to patients, themselves and staff. This study aims to establish the understanding of radiation practice, legislation and risk by orthopaedic surgeons.

Methods:
A nationwide online survey of UK-based orthopaedic surgeons was conducted. Participants answered 18 multiple-choice questions assessing level of radiation safety training, basic principles/knowledge of ionising radiation, relevant legislation and operating practice.

Results:
A total of 406 surgeons completed the survey. 92% reported using intraoperative ionising radiation at least once per week. 38% received no formal training on radiation safety. Knowledge of basic principles of radiation and legislation was limited. There was variable knowledge when labelling an image intensifier machine and choosing its safest orientation. Poor uptake of radiation protection equipment was noted. Only 19% agreed they had adequate training in ionising radiation safety and 27% reported receiving adequate training in equipment emitting ionising radiation in the operating theatre.

Conclusion:
Many orthopaedic surgeons in the UK do not believe they are adequately trained in radiation safety. There is a deficiency amongst practicing surgeons in basic knowledge, relevant legislation and practicalities of the use of ionising radiation in the operating room. This could potentially put patients and health-care professionals at additional risk. We recommend that a standardised national training programme on the basic principles and safety of ionising radiation is implemented for all practicing orthopaedic surgeons.

Advances in knowledge:
This paper is the first UK national survey amongst orthopaedic surgeons and is one of the largest reported internationally.
Laryngeal schwannoma with extralaryngeal extension mimicking a thyroid tumour
Authors: Mikoshi Ayako , Edo Hiromi , Hase Tatsu , Sakima Taishi , Uno Kosuke , Kumazawa Fumihisa , Sato Kimiya , Shinmoto Hiroshi 
Published: July 2021

Objective: A schwannoma is a common benign tumour that can arise anywhere in the body. When it occurs in an unusual location such as the larynx, its differentiation from other tumours can be challenging. Herein, we report a case of a laryngeal schwannoma with extralaryngeal extension that mimicked a thyroid tumour, focusing on its characteristic features on MRI. Methods: A 19-year-old male presented with a mass in the left side of the neck and hoarseness for 2 years. Endoscopy showed a submucosal mass in the laryngeal region. MRI found a well-defined solid mass in the thyroid gland, extending to the larynx through the lower edge of the thyroid cartilage. T2 weighted MRI showed slightly low signal intensity at the central part of the tumour and high signal intensity at the peripheral part of the tumour. Pre-operative imaging suggested that the tumour originated in the thyroid gland. Left thyroidectomy with tumour excision was performed; the tumour was diagnosed as a laryngeal schwannoma with extralaryngeal extension, compressing the thyroid gland. In retrospect, features such as the dumbbell-shape and known as ‘target sign’ on T2 weighted MRI were typical features of schwannoma. Additionally, the tumour’s extension pattern was similar to previous reports of laryngeal schwannomas with extralaryngeal extension. Conclusion: A large laryngeal schwannoma may extend outside the larynx with significant compression of the thyroid gland. Understanding the pattern of extension and familiarity with the features on MRI can improve the preoperative diagnosis accuracy.
Primary clinical study of radiomics for diagnosing simple bone cyst of the jaw
Authors: Jiang Zhe-Yi , Lan Tian-Jun , Cai Wei-Xin , Tao Qian 
Published: July 2021

Objective: To screen the radiomic features of simple bone cysts of the jaws and explore the potential application of radiomics in pre-operative diagnosis of jaw simple bone cysts. Methods: The investigators designed and implemented a case–control study. 19 patients with simple bone cysts who were admitted to the Department of Maxillofacial Surgery, Sun Yat-sen University Affiliated Stomatology Hospital from 2013 to 2019 were included in this study. Their clinical data and cone-beam computed tomography (CBCT) images were examined. The control group consisted of patients with odontogenic keratocyst. CBCT imaging features were analyzed and compared between the patient and control groups. Results: Overall, 10,323 image features were extracted through feature analysis. A subset of 25 radiomic features obtained after feature selection were analyzed further. These 25 features were significantly different between the 2 groups (p < 0.05). The absolute value of correlation coefficient was 0.487–0.775. Gray-level co-occurrence matrix (GLCM) contrast, neighborhood gray tone difference matrix (NGTDM) contrast, and GLCM variance were the features with the highest correlation coefficients. Conclusions: Pre-operative radiomics analysis showed the differences between simple bone cysts and odontogenic keratocysts, can help to diagnose simple bone cysts. Three specific texture features—GLCM contrast, NGTDM contrast, and GLCM variance—may be the characteristic imaging features of simple bone cysts of the jaw.
The empirical formula for calculating the incident air Kerma in intraoral radiographic imaging
Authors: Mirkov Zoran , Rajković Katarina M , Stanković Jovan B , Faj Dario 
Published: July 2021

Objectives: The aim of this paper is to determine the empirical formula for calculating the incident air kerma (Ki), used as a patient dose descriptor in the intraoral radiographic imaging. Methods: The data for the formula were collected during the regular annual inspection of intraoral dental X-ray units in 2018, 2019 and early 2020. The measurement data of 50 X-ray units were processed to develop the formula. Exposure factors for imaging molars of the upper jaw of an average patient in a clinical setting were used in the measurement. The formula validity was statistically evaluated using coefficient of correlation, standard error of the fitted function and the mean relative percentage deviation. Results: The measurement values of the radiation doses and calculated values obtained by using the final formula showed good agreement – the mean relative percentage deviation values less than ±15%. Conclusions: Although there are differences in X-ray units, voltages, manufacturers and device architectures (single-phase and high-frequency), the measurement data comply well with computed ones in all cases.
Toxin-like peptides in plasma, urine and faecal samples from COVID-19 patients
Authors: Brogna Carlo , Cristoni Simone , Petrillo Mauro , Querci Maddalena , Piazza Ornella , Van den Eede Guy 
Published: July 2021

Background: SARS-CoV-2 that causes COVID-19 disease and led to the pandemic currently affecting the world has been broadly investigated. Different studies have been performed to understand the infection mechanism, and the involved human genes, transcripts and proteins. In parallel, numerous clinical extra-pulmonary manifestations co-occurring with COVID-19 disease have been reported and evidence of their severity and persistence is increasing. Whether these manifestations are linked to other disorders co-occurring with SARS-CoV-2 infection, is under discussion. In this work, we report the identification of toxin-like peptides in COVID-19 patients by application of the Liquid Chromatography Surface-Activated Chemical Ionization – Cloud Ion Mobility Mass Spectrometry. Methods: Plasma, urine and faecal samples from COVID-19 patients and control individuals were analysed to study peptidomic toxins’ profiles. Protein precipitation preparation procedure was used for plasma, to remove high molecular weight proteins and efficiently solubilize the peptide fraction; in the case of faeces and urine, direct peptide solubilization was employed. Results: Toxin-like peptides, almost identical to toxic components of venoms from animals, like conotoxins, phospholipases, phosphodiesterases, zinc metal proteinases, and bradykinins, were identified in samples from COVID-19 patients, but not in control samples. Conclusions: The presence of toxin-like peptides could potentially be connected to SARS-CoV-2 infection. Their presence suggests a possible association between COVID-19 disease and the release in the body of (oligo-)peptides almost identical to toxic components of venoms from animals. Their involvement in a large set of heterogeneous extra-pulmonary COVID-19 clinical manifestations, like neurological ones, cannot be excluded. Although the presence of each individual symptom is not selective of the disease, their combination might be related to COVID-19 by the coexistence of the panel of the here detected toxin-like peptides. The presence of these peptides opens new scenarios on the aetiology of the COVID-19 clinical symptoms observed up to now, including neurological manifestations.