Assessment of thermohydraulic performance and entropy generation in an evacuated tube solar collector employing pure water and nanofluids as working fluids.

This study conducts a numerical comparison of the thermal performance of three distinct working fluids (pure water, TiO2, and SiO2 water-based nanofluids) within an evacuated tube solar collector using Computational Fluid Dynamics. The study evaluates thermohydraulic performance alongside global and local entropy generation rates, while considering variations in solar radiation values and inlet mass flow rates. Results indicate that nanofluids demonstrate superior performance under low solar radiation, exhibiting higher outlet temperatures, velocities, thermal efficiency, and exergy efficiency compared to pure water. However, at the higher solar radiation level, the efficiency of SiO2 water-based nanofluid diminishes due to its impact on specific heat. Furthermore, the entropy generation analysis reveals significant reductions with TiO2 water-based nanofluid in all the phenomena considered (up to 79 %). The SiO2 nanofluid performance aligns closely with pure water under high radiation value. This investigation offers valuable insights into the utilization of nanofluids in solar collectors across diverse operating conditions, emphasizing their pivotal role in enhancing overall performance.

Plasma protein signatures for high on-treatment platelet reactivity to aspirin and clopidogrel in peripheral artery disease.

BACKGROUND: A significant proportion of patients with peripheral artery disease (PAD) displays a poor response to aspirin and/or the platelet P2Y12 receptor antagonist clopidogrel. This phenomenon is reflected by high on-treatment platelet reactivity (HTPR) in platelet function assays in vitro and is associated with an increased risk of adverse cardiovascular events. OBJECTIVE: This study aimed to elucidate specific plasma protein signatures associated with HTPR to aspirin and clopidogrel in PAD patients. METHODS AND RESULTS: Based on targeted plasma proteomics, 184 proteins from two cardiovascular Olink panels were measured in 105 PAD patients. VerifyNow ASPI- and P2Y12-test values were transformed to a continuous variable representing HTPR as a spectrum instead of cut-off level-defined HTPR. Using the Boruta random forest algorithm, the importance of 3 plasma proteins for HTPR in the aspirin, six in clopidogrel and 10 in the pooled group (clopidogrel or aspirin) was confirmed. Network analysis demonstrated clusters with CD84, SLAMF7, IL1RN and THBD for clopidogrel and with F2R, SELPLG, HAVCR1, THBD, PECAM1, TNFRSF10B, MERTK and ADM for the pooled group. F2R, TNFRSF10B and ADM were higher expressed in Fontaine III patients compared to Fontaine II, suggesting their relation with PAD severity. CONCLUSIONS: A plasma protein signature, including eight targets involved in proatherogenic dysfunction of blood cell-vasculature interaction, coagulation and cell death, is associated with HTPR (aspirin and/or clopidogrel) in PAD. This may serve as important systems-based determinants of poor platelet responsiveness to aspirin and/or clopidogrel in PAD and other cardiovascular diseases and may contribute to identify novel treatment strategies.

Nanoscale Dynamics of Streptococcal Adhesion to AGE-Modified Collagen.

The adhesion of initial colonizers such as Streptococcus mutans to collagen is critical for dentinal and root caries progression. One of the most described pathological and aging-associated changes in collagen-including dentinal collagen-is the generation of advanced glycation end-products (AGEs) such as methylglyoxal (MGO)-derived AGEs. Despite previous reports suggesting that AGEs alter bacterial adhesion to collagen, the biophysics driving oral streptococcal attachment to MGO-modified collagen remains largely understudied. Thus, the aim of this work was to unravel the dynamics of the initial adhesion of S. mutans to type I collagen in the presence and absence of MGO-derived AGEs by employing bacterial cell force spectroscopy with atomic force microscopy (AFM). Type I collagen gels were treated with 10 mM MGO to induce AGE formation, which was characterized with microscopy and enzyme-linked immunosorbent assay. Subsequently, AFM cantilevers were functionalized with living S. mutans UA 159 or Streptococcus sanguinis SK 36 cells and probed against collagen surfaces to obtain force curves displaying bacterial attachment in real time, from which the adhesion force, number of events, Poisson analysis, and contour and rupture lengths for each individual detachment event were computed. Furthermore, in silico computer simulation docking studies between the relevant S. mutans UA 159 collagen-binding protein SpaP and collagen were computed, in the presence and absence of MGO. Overall, results showed that MGO modification increased both the number and adhesion force of single-unbinding events between S. mutans and collagen, without altering the contour or rupture lengths. Both experimental and in silico simulations suggest that this effect is due to increased specific and nonspecific forces and interactions between S. mutans UA 159 and MGO-modified collagen substrates. In summary, these results suggest that collagen alterations due to aging and glycation may play a role in early bacterial adherence to oral tissues, associated with conditions such as aging or chronic hyperglycemia, among others.

Assigning F-words as ingredients of interventions for children with cerebral palsy functioning at GMFCS IV and V: A scoping review protocol.

Introduction: Children with Cerebral Palsy (CP) functioning at Gross Motor Function Classification System (GMFCS) levels IV and V require "on time" identification and intervention. Interventions offered continue to be a challenge, in high-, but even more so in middle-, and low-income countries. Aim: To describe the methods developed to explore the ingredients of published studies on early interventions in young children with cerebral palsy (CP) at highest risk of being non-ambulant based on the "F-words for child development framework" and the design of a scoping review exploring these ingredients. Method: An operational procedure was developed through expert panels to identify ingredients of published interventions and related F-words. After sufficient agreement among researchers was reached, a scoping review was designed. The review is registered in the Open Science Framework database. The "Population, Concept and Context" framework was used. Population: young children (0-5 years with CP and at highest risk for being non-ambulant (GMFCS levels IV or V); Concept: non-surgical and non-pharmacological early intervention services measuring outcomes from any ICF domain; Context: studies published from 2001 to 2021. After duplicated screening and selection, data will be extracted and quality will be assessed with the American Academy for Cerebral Palsy and Developmental Medicine (AACPDM) and Mixed Methods Appraisal (MMAT) tools. Results: We present the protocol to identify the explicit (directly measured outcomes and respective ICF domains) and implicit (intervention features not explicitly intended or measured) ingredients. Conclusion: Findings will support the implementation of the F-words in interventions for young children with non-ambulant CP.

Translational insights into mechanisms underlying residual venous obstruction and the role of factor XI, P-selectin and GPVI in recurrent venous thromboembolism.

BACKGROUND: Residual venous obstruction (RVO) after deep vein thrombosis (DVT) is considered a risk factor of recurrent venous thromboembolism (VTE), arterial events and post-thrombotic syndrome (PTS). We hypothesized thrombo-inflammatory markers might be associated with RVO and clinical outcomes. MATERIALS AND METHODS: In a DVT cohort with routine RVO-assessment and 5-year follow-up, patients were invited for blood withdrawal after stopping anticoagulants. Thrombin generation potential, coagulation enzyme:inhibitor complexes, soluble platelet markers and clinical markers were measured in platelet-poor plasma. Associations were represented as odds ratio (OR) or hazard ratio (HR) per standard deviation. RESULTS: Patients with RVO (102/306, 33 %) had higher rates of PTS (24 vs. 12 %, p = 0.008), but similar rates of recurrence (16 vs. 15 %, p = 0.91) and arterial events (7 vs. 4 %, p = 0.26). RVO was associated with thrombin peak height (OR 1.40 [1.04-1.88]), endogenous thrombin potential (ETP, OR 1.35 [1.02-1.79]), and CRP (OR 1.74 [1.10-2.75]). Recurrent VTE was associated with ETP (HR 1.36 [1.03-1.81]), FXIa:C1-inhibitor (HR 1.34 [1.04-1.72]), thrombin:antithrombin (HR 1.36 [1.16-1.59]), soluble P-selectin (HR 2.30 [1.69-3.11]), soluble glycoprotein VI (sGPVI, HR 1.30 [1.01-1.69]), D-dimer (HR 1.56 [1.31-1.86]), and factor VIII (HR 1.44 [1.15-1.82]). Arterial events were associated with sGPVI (HR 1.80 [1.25-2.59]). PTS was not associated with any marker. CONCLUSIONS: Our findings indicate RVO was associated with thrombo-inflammation, but this did not predict clinical outcomes in this setting. Importantly, we found recurrent VTE was associated with ongoing coagulation and platelet activation in patients well beyond the acute phase of DVT. Furthermore, sGPVI indicated an increased risk of arterial events, highlighting the role of platelets in arterial thrombosis following DVT.

Discovery of four plasmatic biomarkers potentially predicting cardiovascular outcome in peripheral artery disease.

Peripheral artery disease (PAD) patients have an increased cardiovascular risk despite pharmacological treatment strategies. Biomarker research improving risk stratification only focused on known atherothrombotic pathways, but unexplored pathways might play more important roles. To explore the association between a broad cardiovascular biomarker set and cardiovascular risk in PAD. 120 PAD outpatients were enrolled in this observational cohort study. Patients were followed for one year in which the composite endpoint (myocardial infarction, coronary revascularization, stroke, acute limb ischemia and mortality) was assessed. Patient data and blood samples were collected upon inclusion, and citrated platelet-poor plasma was used to analyze 184 biomarkers in Olink Cardiovascular panel II and III using a proximity extension assay. Fifteen patients reached the composite endpoint. These patients had more prior strokes and higher serum creatinine levels. Multivariate analysis revealed increased plasma levels of protease-activated receptor 1 (PAR1), galectin-9 (Gal-9), tumor necrosis factor receptor superfamily member 11A (TNFRSF11A) and interleukin 6 (IL-6) to be most predictive for cardiovascular events and mortality. Positive regulation of acute inflammatory responses and leukocyte chemotaxis were identified as involved biological processes. This study identified IL-6, PAR1, Gal-9, TNFRSF11A as potent predictors for cardiovascular events and mortality in PAD, and potential drug development targets.

Differences between risk perception and risk-taking are related to impulsivity levels

Background: Although there is broad agreement that perceived risks determine risk-taking behavior, previous research has shown that this association may not be as straightforward as expected. The main objective of this study was to investigate if the levels of impulsivity can explain part of these controversial findings.Method: A total of 1579 participants (Mage = 23.06, from 18 to 60 years; 69.4% women) were assessed for levels of risk perception, risk-taking avoidance, and impulsivity.Results: The results showed that while impulsivity was significantly and negatively related to both risk perception and risk-taking avoidance, the relationship with risk-taking avoidance was significantly stronger than with risk perception. The levels of impulsivity predicted risk-taking avoidance even when controlling for risk perception.Conclusions: These findings indicate that impulsivity can differentially affect risk perception and risk-taking. We propose that the stronger influence of impulsivity on risk-taking is due to the greater reliance of risk-taking, compared with risk perception, on automatic processes guided by impulses and emotions. (AU)

Differences between risk perception and risk-taking are related to impulsivity levels.

Background: Although there is broad agreement that perceived risks determine risk-taking behavior, previous research has shown that this association may not be as straightforward as expected. The main objective of this study was to investigate if the levels of impulsivity can explain part of these controversial findings. Method: A total of 1579 participants (Mage = 23.06, from 18 to 60 years; 69.4% women) were assessed for levels of risk perception, risk-taking avoidance, and impulsivity. Results: The results showed that while impulsivity was significantly and negatively related to both risk perception and risk-taking avoidance, the relationship with risk-taking avoidance was significantly stronger than with risk perception. The levels of impulsivity predicted risk-taking avoidance even when controlling for risk perception. Conclusions: These findings indicate that impulsivity can differentially affect risk perception and risk-taking. We propose that the stronger influence of impulsivity on risk-taking is due to the greater reliance of risk-taking, compared with risk perception, on automatic processes guided by impulses and emotions.

Characterization and Outcomes of SARS-CoV-2 Infection in Patients with Sarcoidosis.

To analyze the clinical characteristics and outcomes of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in patients with sarcoidosis from a large multicenter cohort from Southern Europe and to identify the risk factors associated with a more complicated infection. We searched for patients with sarcoidosis presenting with SARS-CoV-2 infection (defined according to the European Centre for Disease Prevention and Control guidelines) among those included in the SarcoGEAS Registry, a nationwide, multicenter registry of patients fulfilling the American Thoracic Society/European Respiratory Society/World Association of Sarcoidosis and Other Granulomatous Disorders 1999 classification criteria for sarcoidosis. A 2:1 age-sex-matched subset of patients with sarcoidosis without SARS-CoV-2 infection was selected as control population. Forty-five patients with SARS-CoV-2 infection were identified (28 women, mean age 55 years). Thirty-six patients presented a symptomatic SARS-CoV-2 infection and 14 were hospitalized (12 required supplemental oxygen, 2 intensive care unit admission and 1 mechanical ventilation). Four patients died due to progressive respiratory failure. Patients who required hospital admission had an older mean age (64.9 vs. 51.0 years, p = 0.006), a higher frequency of baseline comorbidities including cardiovascular disease (64% vs. 23%, p = 0.016), diabetes mellitus (43% vs. 13%, p = 0.049) and chronic liver/kidney diseases (36% vs. 0%, p = 0.002) and presented more frequently fever (79% vs. 35%, p = 0.011) and dyspnea (50% vs. 3%, p = 0.001) in comparison with patients managed at home. Age- and sex-adjusted multivariate analysis identified the age at diagnosis of SARS-Cov-2 infection as the only independent variable associated with hospitalization (adjusted odds ratio 1.18, 95% conficence interval 1.04-1.35). A baseline moderate/severe pulmonary impairment in function tests was associated with a higher rate of hospitalization but the difference was not statistically significant (50% vs. 23%, p = 0.219). A close monitoring of SARS-CoV-2 infection in elderly patients with sarcoidosis, especially in those with baseline cardiopulmonary diseases and chronic liver or renal failure, is recommended. The low frequency of severe pulmonary involvement in patients with sarcoidosis from Southern Europe may explain the weak prognostic role of baseline lung impairment in our study, in contrast to studies from other geographical areas.

Establishment and characterisation of single cell-derived embryonic stem cell lines from the gilthead seabream, Sparus aurata.

An important bottleneck in fish aquaculture research is the supply and maintenance of embryos, larvae, juvenile and adult specimens. In this context, cell lines represent alternative experimental models for in vitro studies that complement in vivo assays. This allows us to perform easier experimental design and sampling and avoid the sacrifice of animals. Embryonic stem (ES) cell lines have attracted increasing attention because they have the capability to proliferate indefinitely and could be differentiated into any cell type of the organism. To minimise cell heterogeneity and increase uniformity of in vitro studies results, in this manuscript we report the development and characterisation of two single cell-derived ES cell lines (monoclonal) from the morula stage embryos of the gilthead seabream, Sparus aurata, named as SAEC-A3 and SAEC-H7. Both cell lines have been passaged for over 100 times, indicating the establishment of long-term, immortalised ES cell cultures. Sequence analyses confirmed the seabream origin of the cell lines, and growth analyses evidenced their high viability and proliferating activity, particularly in culture medium supplemented with 10-15% fetal bovine serum and 22 °C. Both cell lines showed the ability to generate embryoid bodies and show different sensitivity and response to all-trans retinoic acid. The analysis of epithelial (col1α1) and neuronal (sox3) markers in differentiated cultures revealed that SAEC-A3 tended to differentiate towards epithelial-like cells whereas SAEC-H7 tended to differentiate towards neuronal-like cells. Both cell lines were efficiently transfected with pDsRed2-ER and/or pEGFP-N1 plasmids, indicating that they could represent useful biotechnological tools. Daily expression of pcna showed significant expression rhythms, with maximum levels of cell proliferation during the day-night transition. Currently, these cell lines are being successfully used as experimental models for the study of cellular metabolism, physiology and rhythms as well as for toxicological, pharmacological and gene expression analyses.

Demineralization Inhibition by Two Calcium-releasing Restorative Materials.

OBJECTIVE: To compare the ability of two calcium-releasing restorative materials to inhibit root dentin demineralization in an artificial caries model. METHODS AND MATERIALS: Preparations were made at the cementum-enamel junction of extracted human molars (40, n=10/material) and restored with two calcium-releasing materials (Experimental composite, Pulpdent Corporation and Cention N, Ivoclar Vivadent), a resin composite (Filtek Supreme Ultra, 3M Oral Care), and a resin-modified glass ionomer (RMGI) (Fuji II LC, GC). All materials (other than the RMGI) were used with an adhesive (Scotchbond Universal Adhesive, 3M Oral Care) in the self-etch mode, which was light cured for 10 seconds. All restorative materials were light cured in 2-mm increments for 20 seconds and then finished with a polishing disc. Teeth were incubated (37°C) for 24 hours in water. An acid-resistant varnish was painted onto the teeth around the restoration, leaving a 2-mm border of uncovered tooth. A demineralization solution composed of 0.1 M lactic acid, 3 mM Ca3(PO4)2, 0.1% thymol, and NaOH (to adjust pH=4.5), and a remineralization solution composed of 1.5 mM Ca, 0.9 mM P, and 20 mM Tris(hydroxymethyl)-aminomethane (pH=7.0) were prepared. Specimens were placed in the demineralization solution for 4 hours, followed by the remineralization solution for 20 hours and cycled daily for 30 days. The specimens were embedded, sectioned into 100-µm sections, and the interface between the restorative material and root dentin was viewed with polarized light microscopy. A line was drawn parallel with the zone of demineralization for each tooth. The area of "inhibition" (defined as the area external to the line) or "wall lesion" (defined as the area internal to the line) was measured with image evaluation software. Areas of inhibition were measured as positive values, and areas of wall lesions were measured as negative areas. RESULTS: A one-way analysis of variance (ANOVA) found significant differences between materials for "inhibition/wall lesion" areas in root dentin (p<0.001). Tukey post hoc analysis ranked materials (µm2, mean ±SD): Fuji II LC (5412±2754) > Cention N (2768±1576) and experimental composite (1484±1585) > Filtek Supreme Ultra (-1119±1029). CONCLUSION: The experimental composite and Cention N materials (used with an adhesive) showed net areas of inhibition greater than a reference resin composite, albeit at a lower level than a reference RMGI material (used with no adhesive).

On-line monitoring of photosynthetic activity based on pH data to assess microalgae cultivation.

Microalgae performance of outdoor cultivation systems is influenced by environmental and operating dynamics. Monitoring and control systems are needed to maximise biomass productivity and nutrient recovery. The goal of this work was to corroborate that pH data could be used to monitor microalgae performance by means of data from an outdoor membrane photobioreactor (MPBR) plant. In this system, microalgae photosynthetic activity was favoured over other physical and biological processes, so that the pH data dynamics was theoretically related to the microalgae carbon uptake rate (CUR). Short- and long-term continuous operations were tested to corroborate the relationship between the first derivate of pH data dynamics (pH') and microalgae photosynthetic activity. Short-term operations showed a good correlation between gross pH' values and MPBR performance. An indicator of the maximum daily average microalgae activity was assessed by a combination of on-line pH' measurements obtained in the long-term and a microalgae growth kinetic model. Both indicators contributed to the development of advanced real-time monitoring and control systems to optimise microalgae cultivation technology.

Tratamiento antitrombótico en pacientes que se someten a endoscopias digestivas / Antithrombotic treatment in patients undergoing a gastrointestinal endoscopy

No disponible

Plant-wide modelling in wastewater treatment: showcasing experiences using the Biological Nutrient Removal Model.

Plant-wide modelling can be considered an appropriate approach to represent the current complexity in water resource recovery facilities, reproducing all known phenomena in the different process units. Nonetheless, novel processes and new treatment schemes are still being developed and need to be fully incorporated in these models. This work presents a short chronological overview of some of the most relevant plant-wide models for wastewater treatment, as well as the authors' experience in plant-wide modelling using the general model BNRM (Biological Nutrient Removal Model), illustrating the key role of general models (also known as supermodels) in the field of wastewater treatment, both for engineering and research.

Determinants of COVID-19 disease severity in patients with underlying rheumatic disease.

BACKGROUND: Over the month of April, Spain has become the European country with more confirmed cases of COVID-19 infection, after surpassing Italy on April 2nd. The community of Castile and León in Spain is one of the most affected by COVID-19 infection and the province of León has a total of 3711 cases and 425 deaths so far. Rheumatic patients should be given special attention regarding COVID-19 infection due to their immunocompromised state resulting from their underlying immune conditions and use of targeted immune-modulating therapies. Studying epidemiological and clinical characteristics of patients with rheumatic diseases infected with SARS-CoV2 is pivotal to clarify determinants of COVID-19 disease severity in patients with underlying rheumatic disease. OBJECTIVES: To describe epidemiological characteristics of patients with rheumatic diseases hospitalized with COVID-19 and determine risk factors associated with mortality in a third level Hospital setting in León, Spain. METHODS: We performed a prospective observational study, from 1st March 2020 until the 1st of June including adults with rheumatic diseases hospitalized with COVID-19 and performed a univariate and multivariate logistic regression model to estimate ORs and 95% CIs of mortality. Age, sex, comorbidities, rheumatic disease diagnosis and treatment, disease activity prior to infection, radiographic and laboratorial results at arrival were analysed. RESULTS: During the study period, 3711 patients with COVID-19 were admitted to our hospital, of whom 38 (10%) had a rheumatic or musculoskeletal disease. Fifty-three percent were women, with a mean age at hospital admission of 75.3 (IQR 68-83) years. The median length of stay was 11 days. A total of 10 patients died (26%) during their hospital admission. Patients who died from COVID-19 were older (median age 78.4 IQR 74.5-83.5) than those who survived COVID-19 (median age 75.1 IQR 69.3-75.8) and more likely to have arterial hypertension (9 [90%] vs 14 [50%] patients; OR 9 (95% CI 1.0-80.8), p 0.049), dyslipidaemia (9 (90%) vs 12 (43%); OR 12 (95% CI 1.33-108), p 0.03), diabetes ((9 (90%) vs 6 (28%) patients; OR 33, p 0.002), interstitial lung disease (6 (60%) vs 6 (21%); OR 5.5 (95% CI 1.16-26), p 0.03), cardiovascular disease (8 (80%) vs 11 (39%); OR 6.18 (95% IC 1.10-34.7, p 0.04) and a moderate/high index of rheumatic disease activity (7 (25%) vs 6(60%); OR 41.4 (4.23-405.23), p 0.04). In univariate analyses, we also found that patients who died from COVID-19 had higher hyperinflammation markers than patients who survived: C-reactive protein (181 (IQR 120-220) vs 107.4 (IQR 30-150; p 0.05); lactate dehydrogenase (641.8 (IQR 465.75-853.5) vs 361 (IQR 250-450), p 0.03); serum ferritin (1026 (IQR 228.3-1536.3) vs 861.3 (IQR 389-1490.5), p 0.04); D-dimer (12,019.8 (IQR 843.5-25,790.5) vs 1544.3 (IQR 619-1622), p 0.04). No differences in sex, radiological abnormalities, rheumatological disease, background therapy or symptoms before admission between deceased patients and survivors were found. In the multivariate analysis, the following risk factors were associated with mortality: rheumatic disease activity (p = 0.003), dyslipidaemia (p = 0.01), cardiovascular disease (p = 0.02) and interstitial lung disease (p = 0.02). Age, hypertension and diabetes were significant predictors in univariate but not in multivariate analysis. Rheumatic disease activity was significantly associated with fever (p = 0.05), interstitial lung disease (p = 0.03), cardiovascular disease (p = 0.03) and dyslipidaemia (p = 0.01). CONCLUSIONS: Our results suggest that comorbidities, rheumatic disease activity and laboratorial abnormalities such as C-reactive protein (CRP), D-Dimer, lactate dehydrogenase (LDH), serum ferritin elevation significantly associated with mortality whereas previous use of rheumatic medication did not. Inflammation is closely related to severity of COVID-19. Key Points • Most patients recover from COVID-19. • The use of DMARDs, corticosteroids and biologic agents did not increase the odds of mortality in our study. • Rheumatic disease activity might be associated with mortality.

No effect of ovarian stimulation and oocyte yield on euploidy and live birth rates: an analysis of 12 298 trophectoderm biopsies.

STUDY QUESTION: Does ovarian stimulation affect embryo euploidy rates or live birth rates (LBRs) after transfer of euploid embryos? SUMMARY ANSWER: Euploidy rates and LBRs after transfer of euploid embryos are not significantly influenced by gonadotropin dosage, duration of ovarian stimulation, estradiol level, follicle size at ovulation trigger or number of oocytes retrieved, regardless of a woman's age. WHAT IS KNOWN ALREADY: Aneuploidy rates increase steadily with age, reaching >80% in women >42 years old. The goal of ovarian stimulation is to overcome this high aneuploidy rate through the recruitment of several follicles, which increases the likelihood of obtaining a euploid embryo that results in a healthy conceptus. However, several studies have suggested that a high response to stimulation might be embryotoxic and/or increase aneuploidy rates by enhancing abnormal segregation of chromosomes during meiosis. Furthermore, a recent study demonstrated a remarkable difference in euploidy rates, ranging from 39.5 to 82.5%, among young oocyte donors in 42 fertility centres, potentially suggesting an iatrogenic etiology resulting from different stimulation methods. STUDY DESIGN, SIZE, DURATION: This is a retrospective cohort study that included 2230 in vitro fertilisation (IVF) with preimplantation genetic testing for aneuploidy (PGT-A) cycles and 930 frozen-thawed single euploid embryo transfer (FET) cycles, performed in our centre between 2013 and 2017. PARTICIPANTS/MATERIALS, SETTING, METHODS: A total of 12 298 embryos were analysed for ploidy status. Women were divided into five age groups (<35, 35-37, 38-40, 41-42 and >42 years old). Outcomes were compared between different durations of stimulation (<10, 10-12 and ≥13 days), total gonadotropin dosages (<4000, 4000-6000 and >6000 IU), numbers of oocytes retrieved (<10, 10-19 and ≥20 oocytes), peak estradiol levels (<2000, 2000-3000 and >3000 pg/mL), and sizes of the largest follicle on the day of trigger (<20 and ≥20 mm). MAIN RESULTS AND THE ROLE OF CHANCE: Within the same age group, both euploidy rates and LBRs were comparable between cycles regardless of their differences in total gonadotropin dosage, duration of stimulation, number of oocytes harvested, size of the largest follicles or peak estradiol levels. In the youngest group, (<35 years, n = 3469 embryos), euploidy rates were comparable between cycles with various total gonadotropin dosages (55.6% for <4000 IU, 52.9% for 4000-6000 IU and 62.3% for >6000 IU; P = 0.3), durations of stimulation (54.4% for <10 days, 55.2% for 10-12 days and 60.9% for >12 days; P = 0.2), number of oocytes harvested (59.4% for <10 oocytes, 55.2% for 10-19 oocytes and 53.4% for ≥20 oocytes; P = 0.2), peak estradiol levels (55.7% for E2 < 2000 pg/mL, 55.4% for E2 2000-3000 pg/mL and 54.8% for E2 > 3000 pg/mL; P = 0.9) and sizes of the largest follicle (55.6% for follicles <20 mm and 55.1% for follicles ≥20 mm; P = 0.8). Similarly, in the oldest group (>42 years, n = 1157 embryos), euploidy rates ranged from 8.7% for gonadotropins <4000 IU to 5.1% for gonadotropins >6000 IU (P = 0.3), from 10.8% for <10 days of stimulation to 8.5% for >12 days of stimulation (P = 0.3), from 7.3% for <10 oocytes to 7.4% for ≥20 oocytes (P = 0.4), from 8.8% for E2 < 2000 pg/mL to 7.5% for E2 > 3000 pg/mL (P = 0.8) and from 8.2% for the largest follicle <20 mm to 8.9% for ≥20 mm (P = 0.7). LBRs after single FET were also comparable between these groups. LIMITATIONS, REASONS FOR CAUTION: Although this large study (2230 IVF/PGT-A cycles, 12 298 embryos and 930 single FET cycles) demonstrates the safety of ovarian stimulation in terms of aneuploidy and implantation potential of euploid embryos, a multi-centre study may help to prove the generalisability of our single-centre data. WIDER IMPLICATIONS OF THE FINDINGS: These findings reassure providers and patients that gonadotropin dosage, duration of ovarian stimulation, estradiol level, follicle size at ovulation trigger and number of oocytes retrieved, within certain ranges, do not appear to significantly influence euploidy rates or LBRs, regardless of the woman's age. STUDY FUNDING/COMPETING INTEREST(S): No external funding was received and there are no competing interests to declare. TRIAL REGISTRATION NUMBER: N/A.