bluuebunny/crossref_metadata_2025_split huggingface dataset:
263 Emission factors and fume generation rates of particles from various welding processes
Authors: Khaligh Mozhgan , Hashisho Zaher , Debia Maximilien , Hamre Doug , Wood Gentry , Quemerais Bernadette 
Published: June 2024

Abstract
Welding fumes are classified as a class 1 carcinogen, according to IARC. A conical chamber was built to determine emission factors and fume generation rates of particles from various welding processes. The chamber was calibrated according to the American Welding Society (AWS) standard F1.2:2013 and a high-volume air sampling pump was fixed to the top of the chamber to collect the fumes on 293 mm glass fibre filters located between the cone and the pump. Two welding processes were tested: gas metal arc welding (GMAW) and low power density laser beam welding (LLBW). Tests were performed using seven different types of consumables and different base materials. Consumables included ER70S-2, ER70S-6, ER70S-3, ER308L, ER316L, E316LSi, and ER5356 and the base materials included mild steel, stainless steel, and aluminium. Except for aluminium, which could not ne weld with this particular LLBW machine, the same consumables were used for GMAW and LLBW. Three levels of welding voltages in GMAW and power settings in LLBW were used for each type of consumable to see the effect of voltage and power on particle emission factors and fume generation rates. Additionally, differences between particle emission factors and fume generation rates from GMAW and LLBW for each consumable were compared. Emission factors and fume generation rates increased with increasing voltage/power. Although the fume generation rates were lower for LLBW than for GMAW, the emission factors were higher for LLBW.
306 Proactive prevention of irritant contact dermatitis
Authors: Taylor Helen 
Published: June 2024

Abstract
Irritant contact dermatitis remains the most significant occupational skin disease. The potential impact this condition has on allergic and other systemic ill-health effects means that skin damage has much wider implications. Even before clinical symptoms appear this increased risk of other health issues exists, therefore a proactive approach to preventing irritant contact dermatitis has greater benefits than just prevention of irritant contact dermatitis.
This presentation will briefly outline the importance of detecting subclinical irritant damage. A selection of techniques will be described that can help us detect subclinical irritant damage so that action can be taken prior to the clinical signs. How best to use these techniques will be discussed.
Apomixis beyond trees in the Brazilian savanna: new insights from the orchid Zygopetalum mackayi
Authors: da Costa Gleicyanne Vieira , Alves Mariana Ferreira , Duarte Mariana Oliveira , Caetano Ana Paula Souza , Koehler Samantha , Mayer Juliana Lischka Sampaio 
Published: June 2024

Abstract
n the Neotropics, the focus of apomictic studies predominantly centres on trees within the Brazilian savanna, characterized, mostly as sporophytic and facultative, associated with polyploidy and polyembryony. To enhance our understanding of the mechanisms governing apomixis and sexual reproduction in tropical herbaceous plants, we clarify the relationship between apomixis, chromosome counts, and polyembryony in the epiphytic orchid Zygopetalum mackayi, which forms a polyploid complex within rocky outcrops in both the Brazilian savanna and the Atlantic forest. To define embryo origins and describe megasporogenesis and megagametogenesis, we performed manual self-pollinations in first-day flowers of cultivated plants, considering all three cytotypes (2x, 3x, 4x) of this species. Flowers and fruits at different stages were collected to describe the development and morphology of ovules and seeds considering sexual and apomictic processes. As self-pollination treatments resulted in high fruit abortion in diploids, we also examined pollen tube development in aborted flowers and fruits to search for putative anomalies. Megasporogenesis and megagametogenesis occur regularly in all cytotypes. Apomixis is facultative and sporophytic, and associated with polyploid cytotypes, while diploid individuals exclusively engage in sexual reproduction. Polyembryony is caused mainly by the production of adventitious embryos from nucellar cells of triploids and tetraploids, but also by the development of multiple archesporia in all cytotypes. Like other apomictic angiosperms within the Brazilian savanna, our findings demonstrate that apomixis in Z. mackayi relies on pollinators for seed production. We also consider the ecological implications of these apomictic patterns in Z. mackayi within the context of habitat loss and its dependence on pollinators.
Common mistakes in biostatistics
Authors: D'Arrigo Graziella , El Hafeez Samar Abd , Mezzatesta Sabrina , Abelardo Domenico , Provenzano Fabio Pasquale , Vilasi Antonio , Torino Claudia , Tripepi Giovanni 
Published: June 2024

ABSTRACTBiostatistics plays a pivotal role in developing, interpreting and drawing conclusions from clinical, biological and epidemiological data. However, the improper application of statistical methods can lead to erroneous conclusions and misinterpretations. This paper provides a comprehensive examination of the most frequent mistakes encountered in the biostatistical analysis process. We identified and elucidated 10 common errors in biostatistical analysis. These include using the wrong metric to describe data, misinterpreting P-values, misinterpreting the 95% confidence interval, misinterpreting the hazard ratio as an index of prognostic accuracy, ignoring the sample size calculation, misinterpreting analysis by strata in randomized clinical trials, confusing correlation and causation, misunderstanding confounders and mediators, inadequately codifying variables during the data collection, and bias arising when group membership is attributed on the basis of future exposure in retrospective studies. We discuss the implications of these errors and propose some practical strategies to mitigate their impact. By raising awareness of these pitfalls, this paper aims to enhance the rigor and reproducibility of biostatistical analyses, thereby fostering more robust and reliable biomedical research findings.
Radiomic analysis of computed tomography myocardial texture: a new tool to identify sublclinical cardiac amyloidosis
Authors: Maragna R , Lo Iacono F , Guglielmo M , Baggiano A , Frappampina A , Fusini L , Tassetti L , Volpe A , Junod D , Del Torto A , Fontana M , Treibel T , Moon J , Corino V , Pontone G 
Published: June 2024

Abstract

Background
Cardiac amyloidosis (CA) is an increasingly diagnosed disease sharing several phenotypical features with aortic stenosis (AS).

Purpose
As diagnosing the two diseases has crucial prognostic and therapeutic implications, this study aims to identify a set Powered by Editorial Manager® and ProduXion Manager® from Aries Systems Corporation of stable and discriminative radiomic features derived from cardiac computed tomography (CT) to differentiate them.

Methods
21 patients with cardiac amyloidosis (CA) and 44 with aortic stenosis (AS) were randomly extracted from our database. All patients underwent CT scan. After image preprocessing, 107 radiomics features pertaining to shape and size, first-order statistics and textural classes, were extracted on the LV wall 3D-volume. Radiomic feature selection was based on stability, non-redundancy and relevance based on the Wilcoxon test followed by LASSO algorithm. All these steps were performed on the training set and then applied on the validation and test set. A nested cross-validation, composed of a 7-fold outer cross-validation and a 7-fold inner cross-validation, was performed, using five classifiers (k-nearest neighbors, support vector classifier, decision tree, logistic regression and gradient boosting). Four additional ML models were implemented including: I) age and sex; II) age, sex, BMI, LVEDVi and LVESVi, LV EF and IVS thickness; III) radiomic features, age, and sex; IV) radiomic features and variables included in II).

Results
Feature selection steps reduced the number of features to 10. As logistic regression showed the best performances in the validation set, it was selected for test set prediction obtaining an AUC of 0.92, sensitivity and specificity of 0.857 and 0.864 respectively. ROC curves for the test set, were computed using radiomic features (Figure 1a) and/or clinical variables (Figure 1b). The greatest performances were observed in model IV (AUC=0.96).

Conclusions
The application of radiomics shows promising results in distinguishing left ventricle hypertrophy caused by CA from AS and might be used as a noninvasive tool able to support clinical decision making.
Left atrial volume by cardiac computerized tomography using 3D reconstruction prior to catheter ablation: correlation with echocardiography and clinical outcomes
Authors: Aguiar Neves A I , Nunes F , Leite M , Teixeira R , Almeida M , Lobo A , Almeida J , Fonseca P , Ribeiro Silva M , Oliveira M , Goncalves H , Faria R , Ferreira N , Primo J , Fontes-Carvalho R 
Published: June 2024

Abstract

Introduction
Accurate measurement of left atrial volume index (LAVI) using transthoracic echocardiography (TTE) may be challenging. The use of cardiac computed tomography angiography (CTA) for catheter ablation planning in patients with atrial fibrillation (AF) is common and may help to reduce some of the difficulties in accurately measuring left atrial (LA) volumes, particularly with the use of three-dimensional (3D) reconstruction techniques. However, this method is not yet fully validated.

Methods
Retrospective cohort including patients who underwent an index pulmonary vein isolation (PVI) procedure using CLOSE-protocol guided radiofrequency ablation (between 2018 and 2021 in a tertiary centre. Patients with moderate to severe valvular disease, congenital heart disease or rheumatic valvular disease were excluded. Cardiac CTA was performed in all patients prior to the procedure and 3D reconstruction of the LA was performed using an open-source imaging software. Echocardiographic LAVI measurements were based on the biplane method of disks. LA enlargement was defined by LAVI ≥ 55 ml/m2 on cardiac CTA or LAVI ≥ 35 ml/m2 on TTE.

Results
120 patients (38% female; mean age 58 ± 9.5 years; 68% with a diagnosis of paroxysmal AF) were included in this analysis. Median follow up after PVI was 29 ± 6.5 months. Thirty-nine patients (33%) suffered AF recurrence during this period (after a blanking period of 90 days), of whom nine patients (7.5%) underwent a reablation procedure.
The median LAVI on TTE in this population was 36 ± 5.5 ml/m2. Sixty-seven patients (56%) had LA enlargement when considering a cut-off of LAVI ≥ 35 ml/m2 on TTE. When considering cardiac CTA-derived values after 3D reconstruction of the LA, the median LAVI was 48 ml/m2 and 37 patients (31%) had LA enlargement when considering a cut-off of LAVI ≥ 55 ml/m2 on cardiac CTA. Thirty-four patients had LA enlargement according to both cardiac CTA and TTE measurements. LA measurements using cardiac CTA and TTE strongly correlated with each other, with a correlation coefficient of 0.612 (p&lt;0.001) .
In this cohort, no differences were found with regards to late recurrence or reablation procedures in patients with or without LA enlargement as defined by the cut-offs for LAVI on TTE (LAVI ≥ 35 ml/m2) or cardiac CTA (LAVI ≥ 55 ml/m2). Also, there were no significant differences in atrial volumes derived from TTE or cardiac CTA in patients who suffered AF recurrence when compared to those who did not.

Conclusions
LA volume measurement using 3D reconstruction techniques on cardiac CTA images may be a reasonable alternative to TTE measurements. LA enlargement, independent of measurement technique, did not predict AF recurrence in this population.
Accuracy of computed tomography angiography for the exclusion of coronary artery disease before transcatheter aortic valve implantation
Authors: Lopes V , Almeida P , Fernandes R , Cunha G , Moreira N , Ramalho A , Teixeira R , Goncalves L 
Published: June 2024

Abstract

Introduction
Evaluation for coronary artery disease (CAD) is recommended before transcatheter aortic valve replacement (TAVR). In most cases, this is done with invasive coronary angiography (ICA). Current practice guidelines recommend screening to rule out significant proximal lesions. Computed tomography angiography (CTA) is currently used in the preprocedure planning of TAVR.

Purpose
This study sought to investigate the efficacy of CTA imaging in assessing the proximal coronary arteries, and the feasibility of its use as a screening tool for significant CAD before TAVR.

Methods
We retrospectively analyzed patients referred for TAVR in a single center. Patients with a preprocedure CTA, preprocedure ICA, and without prior proximal percutaneous intervention (PCI) were included in the study. Patients with poor CTA image quality precluding interpretation were excluded. The proximal segment of the coronary arteries was analyzed by CTA to assess for nonsignificant stenosis (0% to 49%), moderate stenosis (50% to 69%), and severe stenosis (≥70%). Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), positive likelihood ratio (LR), negative LR, and Cohen Kappa statistic were analyzed.

Results
A total of 126 patients were included in the analysis: median age was 82 years (IQR 7), and 48% (n=60) of patients were male. The overall prevalence of significant proximal CAD was 9.5%. CTA evaluation revealed a sensitivity of 75%, specificity of 96%, PPV of 24%, NPV of 100%, positive LR of 19.0 (95% CI 10.5-24.4), and negative LR of 0.26 (95% CI 0.08-0.86) for detecting ≥50% stenosis. Using a ≥70% stenosis cutoff, evaluation revealed a sensitivity of 80%, specificity of 99%, PPV of 51%, NPV of 100%, positive LR of 128.8 (95% CI 38.4-432.0), and negative LR of 0.20 (95% CI 0.03-1.16). Cohen Kappa analysis indicated a fair agreement between pre-TAVR CTA and ICA (Cohen k-test 0.35, p &lt;0.001).

Conclusion
Pre-TAVR CTA is a useful tool in screening for significant proximal CAD before TAVR and, due to its high negative predictive value, could spare patients the need for additional invasive testing before the procedure.
The use of sublingual nitroglycerin in patients with severe aortic stenosis before cardiac CT - prospective suty
Authors: Costa G , Silva A L , Ramalho R , Vieira M J , Goncalves L , Teixeira R 
Published: June 2024

Abstract

Introduction
Although nitrates are generally not recommended for patients with severe aortic stenosis, sublingual nitroglycerin (SLN) is widely employed in clinical practice in this population to improve coronary assessment in the planning cardiac computed tomography (CCT) conducted before transcatheter aortic valve implantation (TAVI).

Purpose
To assess the effect on systolic blood pressure (SBP) and the safety of SLN administration in severe aortic stenosis patients undergoing CCT.

Methods
Single-center, prospective, observational study. Patients with severe aortic stenosis undergoing CCT prior to TAVI from June to December 2023 were included in the analysis. Blood pressure readings were taken before and after the imaging procedure. A dosage of 0.5 mg of SLN was given to the SLN group before the exam started. The variation in SBP was evaluated between patients who received and did not receive SLN. Statistical analysis was performed using SPSS 28.0.1.1 software.

Results
A total of 113 patients were included, 52.2% female. The median age of the population was 81.9 (IQR 7) years. SLN was administered in 69.4% (n=77) of patients. The SLN group had a greater prevalence of patients on antihypertensive medications at baseline (47.4% vs. 75.6%, p=0.031).
Before the exam, the average SBP measured 136 (±25) mmHg, notably higher in the SLN group compared to the control (142 vs. 123 mmHg, p&lt;0.001). Following the exam, the mean SBP dropped to 123 (±18) mmHg, although the SLN group maintained a significantly elevated SBP level when compared with the non-SLN group (128 vs. 116 mmHg, p=0.021). The overall mean variation in SBP was -10.1 (±20.9) mmHg, with the SLN group showing a significantly higher decrease in SBP (-17.4 ± 19.3 mmHg) than the non-SLN group (-1.9 ± 20.0 mmHg; p=0.009). Despite a substantial drop in SBP within the SLN group, only two patients experienced post-exam SBP levels below 100 mmHg, whereas one case was identified in the non-SLN group, with no statistically significant difference between the two groups (p=0.568). In addition, no occurrences of symptomatic hypotension were documented.

Conclusion
In this study, SLN administration before CCT led to a considerable reduction in SBP among severe aortic stenosis patients. However, this variation did not hold clinical significance, suggesting that, under careful supervision and when clinically justified, administering SLN to severe aortic stenosis patients may be considered appropriate.
Applying machine learning to diagnose obstructive coronary artery disease using calcium scoring, coronary CT angiography, and clinical data
Authors: Valk J G , Hiemstra P H , Van Dijk J D , Van Dalen J A , Slart R H J A , Tan C O , Mouden M , Vendel B N 
Published: June 2024

Abstract

Introduction
Traditional diagnostic risk assessment in patients undergoing CT-based calcium scoring (CACS) and coronary CT angiography (CCTA) is based on a limited number of clinical and imaging findings. Machine learning has demonstrated its suitability to use a greater number of features to model complex non-linear relations leading to a more accurate diagnostic performance. Our aim was to develop and validate a machine learning model to diagnose obstructive coronary artery disease (oCAD) in patients without prior history of CAD, using CACS, CCTA and clinical data.

Methods
We retrospectively included 1254 patients without a prior history of CAD who underwent CACS and CCTA. Cardiac risk factors; smoking, hypertension, hypercholesterolemia, diabetes, family history of CAD; age; gender; body mass index; creatinine serum values; CCTA-outcomes, CACS and medication usage were registered at time of the scan. The entire dataset was split 4:1 into a training and test dataset, respectively. A XGBboost model was developed on the training set using fivefold stratified cross-validation and hyperparameter tuning. The test dataset was used to compare the diagnostic performance of the model to the performance of expert readers, looking at specificity, sensitivity, and ROC-analysis. The primary endpoint was oCAD on invasive coronary angiographies (ICA). Patients who were not referred for ICA were presumed not to have oCAD.

Results
A total of 85 (6.8%) of the 1254 patients (46% male, 60 ± 8 years of age) were diagnosed with oCAD. Age, total calcium score, body mass index, left anterior descending artery calcium score, and creatinine serum level were the highest-ranking features to predict oCAD. The performance of the XGBoost model did not differ from expert readers in predicting oCAD (p=0.84). The model and expert readers achieved a specificity of 0.97 vs 0.95, sensitivity of 0.71 vs 1.00, and an AUC of 0.96 vs 0.97, respectively.

Conclusion
The XGBoost model demonstrated a diagnostic performance comparable to that of expert readers. Features with negative predictive value in the diagnosis of oCAD were most valuable to the model such as high CACS. Currently, the model cannot replace expert readers, but it can contribute to the consistency of oCAD diagnoses and can be used to assist physician experts.Feature importance of the XGBoost model ROC Curve of the XGBoost model
Current practice of coronary CT: indications and results - real world data
Authors: Almeida I , Mendonca T , Ramos R , Cruz Ferreira R 
Published: June 2024

Abstract

Introduction
Current indications for coronary artery disease (CAD) evaluation through computed tomography (CT) are well established.

Purpose
To evaluate the real world experience regarding indications to coronary CT, results and subsequent patient management.

Material and methods
Single center retrospective analysis of patients´ admitted to perform a coronary CT during 2023. Demographic and clinical characteristics of patients, indications for the CT, exam data and management were recorded.

Results
484 patients were included (mean age 67.5 years, 52.2% male). In the first group, 283 (58.4%) patients presented with chest pain and no known CAD. Of these, 47.7% had positive ischemia tests, ventricular repolarization or echocardiographic wall motion abnormalities. The other 52.3% were referred due to chest pain only or despite negative ischemia tests. In the second group, 110 (22.8%) patients were referred to exclude CAD in the presence of other cardiac conditions: valvular heart disease (18.2%), ventricular ectopic beats (22.8%), heart failure (30.0%), cardiac transplantation (10.9%), acute conditions (10%) and congenital heart disease (8.2%). The exams´ results were divided in the following categories: absence of CAD, non-obstructive CAD (stenosis &lt;50%), obstructive CAD (stenosis &gt;50%) or inconclusive (non-assessable left main and/or proximal anterior descending artery or elevated atherosclerotic burden precluding contrast injection). In the first group, 81.6% presented none or non-obstructive CAD, 8.8% obstructive CAD and 9.6% were inconclusive. In the second group, 85.5% presented none or non-obstructive CAD, 7.3% obstructive CAD and 6.9% were inconclusive. Depending on medical decision, some patients with obstructive and inconclusive CAD were referred to coronary angiography (CA). At the present time, 10 patients performed CA, of which 3 was submitted to percutaneous intervention. In the third group, 91 (18.8%) patients were referred to coronary CT to evaluate coronary artery anomalies (CAA) (9.9%) and known CAD, namely, coronary stents (11%), coronary artery bypass grafts (CABG) (69.2%) and to decide surgical revascularization based on an occluded artery in CA (9.9%). Regarding CAA, only 1 patient was diagnosed with a malignant course and submitted to an unroofing procedure. Regarding previously revascularized patients: coronary stents and CABG were adequately evaluated in all proposed patients (only 1 and 2, respectively, presented cclusive lesions and were referred to CA). Of the patients presented with a coronary occlusion on CA, 5 (55.6%) had a good distal vessel so they were referred to surgical revascularization.

Conclusion
Our data is in accordance with current published studies and guidelines showing that coronary CT is a well stablished exam to safely exclude CAD in a low-intermediate risk population as well as some previously revascularized patients.