Performance comparison of two thermodenuders in Volatility Tandem DMA measurements

AbstractVolatility Tandem Differential Mobility Analysers (VTDMAs) are widely used for determining the volatile and refractory fractions and thus the mixing state of aerosols particles. A three-channel VTDMA consisting of two thermodenuders (TDs) with distinct designs (i.e., the NanoTD, having a straight tube design, and a coiled TD; cTD) and a by-pass line was built and fully characterized. Both TDs were tested using laboratory-generated aerosol particles (single compound and core–shell particles) as well as atmospheric aerosols observed at an urban background station. The NanoTD exhibited high particle penetration efficiency and negligible thermophoretic losses, making it advantageous for ultrafine particle analysis, especially in environments with low particle concentration. The cTD allows longer particle residence time for the same flow rate, resulting in higher particle volatilization in some cases. Higher particle losses in this TD, both thermophoretic and diffusional, pose a limitation when dealing with low particle concentrations.The difference in the performance between the thermodenuders was only noticed at intermediate temperatures, at which particle volume loss becomes more pronounced. These temperatures vary among aerosols, since the volatilization rate depends on the chemical complexity and size of the particles sampled. Differences in the aerosol volume fraction remaining after heating with the two TD designs exhibited a maximum of 20% for single-compound particles and 12% for urban background aerosols. Measurements using core–shell particles yielded differences of up to 21% in particle volatilization, independently of particle size, when comparing the system using either of the two TD designs. Similar results were obtained with the two TD designs at higher operating temperatures (e.g., 230°C), indicating that at this temperature most of the material on the particles was evaporated

Evaluation of cardiotoxicity five years after 2D planned, non-simulated, radiation therapy for left breast cancer

Kyriaki Pistevou-Gompaki1, Apostolos Hatzitolios2, Nikos Eleftheriadis2, Evaggelos Boultoukas2, George Ntaios2, Ioannis Andronikidis2, Ioannis Tzitzikas11Department of Radiation Oncology; 2First Propedeutic Department of Internal Medicine, AHEPA Hospital, Aristotle University, Thessaloniki, GreeceIntroduction: Radiation treatment has been associated with radiation induced cardiotoxicity, especially with older, long-outdated, techniques. Such complications include pericarditis, myocardial fibrosis, valvular injury, ischemic heart disease, and myocardial infarction.Aim: To assess the effect of outdated breast radiation therapy (RT) – using a diagnostic CT scanner in the absence of a CT simulator – on cardiac function in women with stage II left breast cancer.Patients and Methods: Sixty-two women under 65 with stage II left breast cancer who received post-operative RT using a diagnostic computed tomography scanner were studied between 1997 and 2001. Participants underwent a clinical interview, ECG, and echocardiography before and 6 months and 5 years after RT.Results: There was no serious cardiotoxicity at 6 months and 5 years after radiotherapy. A 23% increase in hypertensive patients, and a slight decrease (2.3%) in ejection fraction was observed after 5 years, with 3 patients (5%) developing abnormalities. Two patients presented abnormal electrocardiographic findings within 6 months of RT.Conclusion: Our study showed that RT for left breast cancer was not associated with significant alteration in heart morbidity or mortality within 5 years of treatment, despite the lack of a simulator.Keywords: radiotherapy, breast cancer, cardiotoxicity, acute myocardial infraction, ischemic heart diseas

Perceptions about effective risk management. The crucial role of internal audit and management. Evidence from Greece

In the aftermath of the financial crisis, many companies have implemented extensive risk management procedures. Additionally, internal audit has increasingly attracted the attention of managers as it constitutes the core of modern corporate governance. However, regarding Greek companies, there is a lack of empirical research on factors that affect risk management. Therefore, the purpose of the present paper is to analyze specific factors associated with effective risk management. Primary data were collected using questionnaires distributed to employees in companies that are listed on the Athens Exchange. Multiple regression analysis was conducted in order to examine the relationship between effective risk management, risk based internal audit, internal auditors’ involvement in risk management and top management support. Our findings demonstrate that the above factors contribute positively to effective risk management

Radiomics and Machine Learning for Skeletal Muscle Injury Recovery Prediction

Injuries; Muscles; RadiomicsLesions; Músculs; RadiòmicaLesiones; Músculos; RadiómicaRadiomics as a novel quantitative approach to medical imaging is an emerging area in the field of radiology. Artificial intelligence offers promising tools for exploiting and analyzing radiomics. The objective of the present study is to propose a methodology for the design, development, and evaluation of machine learning (ML) models for the prediction of the recovery progress of skeletal muscle injury over time in rats using radiomics. Radiomics were extracted from contrast enhanced computed tomography (CT) data and ML algorithms were trained and compared for their predictive value based on different CT imaging parameters. Ten different ML regression algorithms were tested and the optimal combination of radiomics for each algorithm and CT imaging parameter settings combination was studied. The best ensemble learning model, trained on the 70 kVp, 100 mA imaging parameter dataset, achieved a mean absolute error score of 1.22. The results suggest that radiomics extracted from CT images can be used as input in ML regression algorithms to predict the volume of a skeletal muscle injury in rats. Moreover, the results show that CT imaging settings impact the predictive performance of the ML regression models, indicating that lower values of tube current and peak kilovoltage contribute to more accurate predictions.10.13039/100010671-European Union’s Horizon Research and Innovation Program (Grant Number: 761031

Characterization of a murine mixed neuron-glia model and cellular responses to regulatory T cell-derived factors

Abstract One of the unmet clinical needs in demyelinating diseases such as Multiple Sclerosis (MS) is to provide therapies that actively enhance the process of myelin regeneration (remyelination) in the central nervous system (CNS). Oligodendrocytes, the myelinating cells of the CNS, play a central role in remyelination and originate from oligodendrocyte progenitor cells (OPCs). We recently showed that depletion of regulatory T cells (Treg) impairs remyelination in vivo, and that Treg-secreted factors directly enhance oligodendrocyte differentiation. Here we aim to further characterize the dynamics of Treg-enhanced oligodendrocyte differentiation as well as elucidate the cellular components of a murine mixed neuron-glia model. Murine mixed neuron-glia cultures were generated from P2–7 C57BL/6 mice and characterized for percentage of neuronal and glial cell populations prior to treatment at 7 days in vitro (div) as well as after treatment with Treg-conditioned media at multiple timepoints up to 12 div. Mixed neuron-glia cultures consisted of approximately 30% oligodendroglial lineage cells, 20% neurons and 10% microglia. Furthermore, a full layer of astrocytes, that could not be quantified, was present. Treatment with Treg-conditioned media enhanced the proportion of MBP+ oligodendrocytes and decreased the proportion of PDGFRα+ OPCs, but did not affect OPC proliferation or survival. Treg-enhanced oligodendrocyte differentiation was not caused by Treg polarizing factors, was dependent on the number of activation cycles Treg underwent and was robustly achieved by using 5% conditioned media. These studies provide in-depth characterization of a murine mixed neuron-glia model as well as further insights into the dynamics of Treg-enhanced oligodendrocyte differentiation

CAST constraints on the axion-electron coupling

In non-hadronic axion models, which have a tree-level axion-electron interaction, the Sun produces a strong axion flux by bremsstrahlung, Compton scattering, and axiorecombination, the "BCA processes." Based on a new calculation of this flux, including for the first time axio-recombination, we derive limits on the axion-electron Yukawa coupling gae and axion-photon interaction strength ga using the CAST phase-I data (vacuum phase). For ma <~ 10 meV/c2 we find ga gae < 8.1 × 10−23 GeV−1 at 95% CL. We stress that a next-generation axion helioscope such as the proposed IAXO could push this sensitivity into a range beyond stellar energy-loss limits and test the hypothesis that white-dwarf cooling is dominated by axion emission

DIAbetic macular oedema aNd diode subthreshold micropulse laser (DIAMONDS) : Ppotocol for a randomised clinical trial

Background In the UK, macular laser is the treatment of choice for people with diabetic macular oedema with central retinal subfield thickness (CST) < 400 μm, as per National Institute for Health and Care Excellence guidelines. It remains unclear whether subthreshold micropulse laser is superior and should replace standard threshold laser for the treatment of eligible patients. Methods DIAMONDS is a pragmatic, multicentre, allocation-concealed, randomised, equivalence, double-masked clinical trial that aims to determine the clinical effectiveness and cost-effectiveness of subthreshold micropulse laser compared with standard threshold laser, for the treatment of diabetic macular oedema with CST < 400 μm. The primary outcome is the mean change in best-corrected visual acuity in the study eye from baseline to month 24 post treatment. Secondary outcomes (at 24 months) include change in binocular best corrected visual acuity; CST; mean deviation of the Humphrey 10–2 visual field; change in percentage of people meeting driving standards; European Quality of Life-5 Dimensions, National Eye Institute Visual Functioning Questionnaire-25 and VisQoL scores; incremental cost per quality-adjusted life year gained; side effects; number of laser treatments and use of additional therapies. The primary statistical analysis will be per protocol rather than intention-to-treat analysis because the latter increases type I error in non-inferiority or equivalence trials. The difference between lasers for change in best-corrected visual acuity (using 95% CI) will be compared to the permitted maximum difference of five Early Treatment Diabetic Retinopathy Study (ETDRS) letters. Linear and logistic regression models will be used to compare outcomes between treatment groups. A Markov-model-based cost-utility analysis will extend beyond the trial period to estimate longer-term cost-effectiveness. Discussion This trial will determine the clinical effectiveness and cost-effectiveness of subthreshold micropulse laser, when compared with standard threshold laser, for the treatment of diabetic macular oedema, the main cause of sight loss in people with diabetes mellitus

Coronary artery bypass surgery in a patient with Kartagener syndrome: a case report and literature review

Kartagener syndrome consists of congenital bronchiectasis, sinusitis, and total situs inversus in half of the patients. A patient diagnosed with Kartagener syndrome was reffered to our department due to 3-vessel coronary disease. An off-pump coronary artery bypass operation was performed using both internal thoracic arteries and a saphenous vein graft. We performed a literature review for cases with Kartagener syndrome, coronary surgery and dextrocardia. Although a few cases of dextrocardia were found in the literature, no case of Kartagener syndrome was mentioned

Self-reported risk of obstructive sleep apnea syndrome, and awareness about it in the community of 4 insular complexes comprising 41 Greek Islands

Obstructive Sleep Apnea Syndrome (OSAS) is a chronic disease that significantly increases morbidity and mortality of the affected population. There is lack of data concerning the OSAS prevalence in the insular part of Greece. The purpose of this study was to investigate the self-reported prevalence of OSAS in 4 Greek insular complexes comprising 41 islands, and to assess the awareness of the population regarding OSAS and its diagnosis. Our study comprised 700 participants from 41 islands of the Ionian, Cyclades, Dodecanese and Northeast Aegean island complexes that were studied by means of questionnaires via a telephone randomized survey (responsiveness rate of 25.74%). Participants were assessed by the Berlin Questionnaire (BQ) for evaluation of OSA risk, by the Epworth Sleepiness Scale (ESS) for evaluation of excessive daytime sleepiness, and by 3 questions regarding the knowledge and diagnosis of OSAS. The percentage of participants at high risk according to BQ was 27.29% and the percentage of people who were at high risk according to ESS was 15.43%. A percentage of 6.29% of the population was at high risk for OSAS (high risk both in BQ and ESS). A high percentage of 73.43%, were aware of OSAS as a syndrome however a significantly less percentage (28.00%) was aware of how a diagnosis of OSAS is established. The community prevalence of OSAS in Greek islands in combination with the low-level awareness of the OSAS diagnostic methods highlights the need for development of health promotion programs aiming at increasing the detection of patients at risk while increasing the awareness of OSAS