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Electrical and fast imaging measurements are performed on an experimental device designed to study the dynamics of electric arcs in the DC regime. The work presented here investigates the relationship between electrical fluctuations and material ejection from the electrode surface. Cross-analysis of the electrical and imaging data reveals a significant correlation between electrical fluctuations in the kHz range and particle emission from the electrode surface. Different types of ejection are presented and a study of the dynamics of the ejected particles is carried out through the analysis of a statistically significant number of trajectories. [ABSTRACT FROM AUTHOR]

This study explores the application of machine learning techniques for detecting and tracking plasma filaments around the boundary of magnetically confined tokamak plasmas. Plasma filaments, also called blobs, are responsible for enhanced turbulent transport across magnetic field lines, and their accurate characterization is crucial for optimizing the performance of magnetic fusion devices. We present a novel approach that combines machine learning methods applied to data obtained from ultra-fast cameras, including YOLO (You Only Look Once) for object detection, semantic segmentation, and specific tracking methods. This approach enables fast and accurate detection and tracking of filaments while overcoming the limitations of conventional methods, which are time-consuming and prone to human subjectivity. A significant advance in our study lies in the development of a method for automatically labeling a large batch of data, which greatly facilitates the training of supervised machine learning algorithms. Using these techniques, we obtained promising results demonstrating a significant improvement over conventional tracking methods, achieving a detection accuracy of up to 98.8%, while reducing the inference time per frame by 15% to 31% compared to conventional Kalman filter tracking. These results open up new perspectives for investigating turbulent phenomena in tokamaks, and could have important implications for the development of controlled nuclear fusion., Competing Interests: Declarations Competing interests The authors declare no competing interests., (© 2024. The Author(s).)

Introduction: Ensuring optimal blood transfusion practices relies on a robust expertise base that is indispensable across various professional fields. Recognizing this imperative, the current study aims to assess the knowledge levels of healthcare personnel and enhance transfusion quality through targeted continuing training initiatives., Methods: The preliminary survey was based on an anonymous questionnaire and we used correct response rate (CRR) as the main parameter evaluating the baseline level of knowledge. Then blood transfusion education sessions which focused on transfusion shortcomings were carried out. Finally, we assessed the impact of this training on the baseline education., Results: From the total of 789 questionnaires distributed, we garnered 331 responses 23 from healthcare staff. The overall CRR for questions related to transfusion procedure knowledge was 33%. Notably, the per-transfusion step exhibited the highest control with CRR of 55% while noticeable gaps were observed in the pre-transfusion (CRR = 22%) and post-transfusion (CRR = 13%) phases. Profession wise variations in CRR were evident, with nurses recording the lowest percentage (CRR = 29%) compared to physicians (CRR = 39%) and technicians (CRR = 34%). Substantial differences were observed in the interpretation of Ultimate Control in the Patient's Bed (UCPB) among professions, especially affecting ABO identity, compatibility, and incompatibility cases. Following the blood transfusion training, attended by 105 participants, only 99 participants responded to the questionnaire post-training, expressing high satisfaction with the covered modules (80%). The knowledge enhancement encompassed all transfusion phases and the interpretation of clinical cases, notably ABO compatibility. Overall, there was a significant improvement in CRR from 33 to 53% ( p  < 0.001)., Conclusion: This study demonstrates that the evaluation of knowledge should be carried out on a continuous manner in order to detect gaps in the professional sector and to ensure the effectiveness of training through well-targeted educational programs., Supplementary Information: The online version contains supplementary material available at 10.1007/s12288-024-01778-y., Competing Interests: Conflict of InterestThe authors declare that there is no conflict of interest., (© Indian Society of Hematology and Blood Transfusion 2024. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.)

Magnetically confined fusion plasmas are subject to various instabilities that cause turbulent transport of particles and heat across the magnetic field. In the edge plasma region, this transport takes the form of long filaments stretched along the magnetic field lines. Understanding the dynamics of these filaments, referred to as blobs, is crucial for predicting and controlling their impact on reactor performance. To achieve this, highly resolved passive fast camera measurements have been conducted on the COMPASS tokamak. These measurements are analyzed using both conventional tracking methods and a custom-developed machine-learning approach designed to characterize more particularly the mutual interactions between filaments. Our findings demonstrate that up to 18% of blobs exhibit mutual interactions in the investigated area close to the separatrix, at the border between confined and nonconfined plasma. Notably, we present direct observations and radial dependence of blob coalescence and splitting, rapid reversals in the propagation direction of the blob, as well as their dependence on the radial position. The comparison between observations realized with passive and gas puff imaging does not evidence any significant bias due to the use of the latter technique.

Background: Estimation of HLA (Human leukocyte Antigen) alleles' frequencies in populations is essential to explore their ethnic origin. Anthropologic studies of central Tunisian population were rarely reported. Then, in this work, we aimed to explore the origin of central Tunisian population using HLA alleles and haplotypes frequencies., Methods: HLA class I (A, B, C) and HLA class II (DRB1, DQA1, DQB1) loci genotyping of 272 healthy unrelated organ donors was performed by Polymerase Chain Reaction-Sequence Specific Oligonucleotide (PCR-SSO). We compared central Tunisians with other populations (Arabs, Berbers, Mediterraneans, Europeans, Africans, etc.) using alleles and haplotypes frequencies, genetic distances, Neighbour-Joining dendrogram and correspondence analysis., Results: Among the 19 HLA A alleles, the 26 HLA B alleles, the 13 HLA C alleles, the 15 HLA DRB1 alleles, the 6 HLA DQA1 alleles and the 5 HLA DQB1 alleles identified in the studied population, HLA A*02 (22.8%), HLA B*50 (13.1%), HLA C*06 (21.8%), HLA DRB1*07 (17.8%), HLA DQA1*01 (32.1%) and HLA DQB1*03 (31.6%) were the most frequent alleles. The extended haplotypes HLA A*02-B*50-C*06-DRB1*07-DQA1*02-DQB1*02 (1.97%) was the most frequent HLA six-loci haplotype., Conclusion: Central Tunisians were very close to other Tunisian populations, to Iberians and North Africans. They were rather distant from sub-Saharan populations and eastern Mediterraneans especially Arabs although the strong cultural and religious impact of Arabs in this population., (© 2024. The Author(s).)

Our study is the first study to investigate the effect of SNPs in CYP3A5, CYP3A4, ABCB1 and POR genes on the incidence of tremors, nephrotoxicity, and diabetes mellitus. A total of 223 renal transplant patients receiving tacrolimus and mycophenolate mofetil (MMF) were recruited. Both adults and children patients participated in the study. Genotyping was performed using PROFLEX-PCR followed by RFLP. MPA and tacrolimus plasma concentrations were measured by immunoassay. The AUC0-12h of MMF was estimated by a Bayesian method. We found a statistically significant association between the CYP3A5*3 and CYP3A4*1B genotypes and the tacrolimus exposure. We found a lower occurrence of nephrotoxicity (p = 0.03), tremor (p = 0.01), and new-onset diabetes (p = 0.002) associated with CYP3A5*1 allele. The CYP3A4*1B allele was significantly associated with a lower occurrence of new-onset diabetes (p = 0.026). The CYP3A5*1 allele was significantly associated with an increased risk of acute and chronic rejection (p = 0.03 and p < 0.001, respectively). Our results support the usefulness of tacrolimus pharmacokinetics in pre-kidney transplant assessments., (© 2024. The Author(s), under exclusive licence to Springer Nature Limited.)

Background: We aimed to describe the episodes and trends of admissions for community-acquired Respiratory Infections (RI) over a 12-year period and to assess the impact of Haemophilus influenza type b (Hib) vaccine on RI admissions in children aged up to 3 years., Methods: We conducted a twelve-year retrospective observational study on all community-acquired RI admitted to Fattouma Bourguiba Hospital in Monastir Governorate (Tunisia) from 1 January 2002 to 31 December 2013. RI cases were selected from the Regional Registry of Hospital Morbidity. Data were coded according to ICD-10. To assess the impact of the Hib vaccine, three cohorts were defined based on vaccine status (unvaccinated cohort, first vaccinated cohort (VC) by monovalent form and second VC by pentavalent combination)., Results: Admissions for RI represented 17.6% (CI95%: 17.3-18.1) of all communicable diseases hospitalizations (n = 6 061/34 289). The crude incidence rates (CIR) per 100,000 inh were 24.2 for upper RI (URI) and 77.5 and for Lower RI (LRI) (p < 0.0001). Pneumonias represented 53.9% of LRI. Sex-ratio (male/female) was 1.12 for URI and 1.64 for LRI (p < 0.0001). At admission, the median age was 22 years (IQR: 3-52). Admission for Pneumonia increased significantly during study period (slope 'b' = 5.16; p < 0.0001) especially in children up to 5 years old (slope 'b' = 5.53) and in elderly (slope 'b' = 2.13). Among children up to 3 years old, the CIRs per 100,000 for Hib pneumonia admission were 11.6 in Non-Vaccinated Cohort (NVC), 10.6 in Vaccinated Cohort (VC) by protocol 1 (Hib Vaccine monovalent) and 0.80 in VC by protocol 2 (pentavalent vaccine combination).The relative risk reduction was 99% for protocol 2 (p < 0.001)., Conclusion: Admissions for RI in a  tertiary level hospital were common with an increasing trend. The Hib immunization program, in particular the pentavalent combination, has had a positive impact on the reduction of related acute diseases.

Background: Coronary artery disease (CAD) and its ultimate consequence - myocardial infarction (MI) - are major causes of sudden cardiac death (SCD). Previous studies have demonstrated the role of genetic polymorphisms in the risk of SCD and ventricular arrhythmia (VA) during MI., Objectives: To investigate the association between single nucleotide polymorphisms (SNPs) of genes implicated in congenital cardiac arrhythmias and the risk of developing VA in the context of MI., Material and Methods: We performed a case-control study in which we genotyped 4 SNPs (rs11708996, rs10428132, rs9388451, and rs2200733) in 469 subjects using amplification refractory mutation system (ARMS) and a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). These SNPs are located in the SCN5A, SCN10A, HEY2, and PITX2 genes, respectively. We first compared 70 patients who had developed VA in the context of MI with 141 healthy controls; next, we compared VA patients with 258 MI patients who did not develop VA during a 1-year follow up. The statistical analyses were adjusted for sex and age., Results: Compared to the controls, 2 polymorphisms were significantly associated with the development of VA during MI, located in SCN5A rs11708996 (p = 0.001) and SCN10A rs10428132 (p = 0.001). Similar results were found when comparing VA cases with patients without VA. No associations of HEY2 and PITX2 polymorphisms were observed., Conclusions: Our results suggest that the rs11708996 and rs10428132 polymorphisms of the SCN5A and SCN10A genes may contribute to an elevated risk of developing VA in the context of MI. The associated alleles or genotypes may be used to predict the risk, and thus prevent eventual SCD.

Purpose: Clopidogrel non-responsiveness is multifactorial; several genetic and non-genetic factors may contribute to impaired platelet inhibition. The goal of this study is to determine the effect of the cytochrome P450 CYP2C19*2 polymorphism on the platelet response to clopidogrel in patients with and without diabetes mellitus (DM)., Methods: We conducted an observational study in patients with coronary artery disease and consequent exposure to clopidogrel therapy (75 mg/day for at least 7 consecutive days). We have analyzed two groups of patients: group I (DM patients) and group II (non-diabetes mellitus patients). Platelet reactivity was assessed by the VerifyNow P2Y12 assay and high on clopidogrel platelet reactivity (HPR) was defined as P2Y12 reaction units (PRU) ≥ 208. Genotyping for CYP2C19*2 polymorphism was performed by PCR-RFLP., Results: We have included 150 subjects (76 DM and 74 non-diabetes mellitus patients). The carriage of CYP2C19*2 allele, in DM patients, was significantly associated to HPR (odds ratio (OR) 4.437, 95% confidence interval (CI) 1.134 to 17.359; p = 0.032). Furthermore, 8.4% of the variability in percent inhibition by clopidogrel could be attributed to CYP2C19*2 carrier status. However, in non-diabetes mellitus patients, there was no significant difference in platelet response to clopidogrel according to the presence or absence of CYP2C19*2 allele carriage (OR 1.260, 95% CI 0.288 to 5.522; p = 0.759)., Conclusions: Our study suggests that the carriage of CYP2C19*2 polymorphism, in DM patients, might be a potential predictor of persisting HPR in these high-risk individuals., Trial Registration: Clinical Trials.gov NCT03373552 (Registered 13 December 2017).

Thiopurine-S-methyltransferase (TPMT) and inosine triphosphate pyrophosphatase (ITPA) are crucial enzymes involved in the metabolism of thiopurine drugs. Significant interethnic variation in the expression of TPMT and ITPA is caused by single nucleotide polymorphisms of genes encoding these proteins. The aim of this study was to describe the distribution of TPMT and ITPA polymorphisms in healthy Tunisian subjects and to establish the metabolizer status of thiopurine drugs in this population. A total of 309 healthy Tunisian subjects were recruited among blood donors of Fattouma Bourguiba Hospital of Monastir. A written informed consent was obtained from all subjects. Whole blood samples were collected from every subject in ethylenediaminetetraacetic acid tubes. TPMT (c.238 G > C, c.460 G > A and c.719A > G) and ITPA (c.94C > A and IVS2+21A > C) mutations were genotyped using polymerase chain reaction-restriction fragment length polymorphism. The observed frequencies of TPMT*3A and TPMT*3C alleles were both 0.8%. The phenotype distribution of TPMT was bimodal: 96.8% of subjects were extensive metabolizers and 3.2% were intermediate metabolizers. Genotyping of ITPA revealed frequencies of 9% and 3% for IVS2+21A > C and c.94C > A mutations, respectively. Accordingly, a trimodal phenotype distribution was found: 75.4% of the subjects were extensive metabolizers, 23.4% were intermediate metabolizers, and 1.2% wereslow metabolizers. Combination of TPMT and ITPA genotyping has revealed that a quarter of the Tunisian Population carries polymorphisms that reduce the metabolic activities of these enzymes.

The clinical and biological manifestations of visceral leishmaniasis are often confusing, most particularly because it can mimic and lead to a variety of hematological disorders. The aim of this study was to investigate the hematologic abnormalities observed in infantile visceral leishmaniasis from January 2000 and December 2013. The study included 35 children with a mean age of 3.5 years. Clinical manifestations were dominated by splenomegaly, fever, and paleness, defining the classic triad in 16% of our patients. Anemia was present in all patients. Leukopenia was found in 51% of the cases. Thrombocytopenia was observed in 48% of our patients and 36% had pancytopenia. All cases were confirmed by the presence of Leishman bodies (amastigotes) in the bone marrow smears. Quantitative and qualitative megakaryocyte abnormalities were found. Similarly, dysgranulopoiesis was observed in 31% of the cases, eosinophilia was present in 6%, erythroid hypoplasia in 3%, and erythroid hyperplasia in 34%. Different features of dyserythropoiesis were revealed in 71% of the patients with images of hemophagocytosis in 6% and multiple dysplasias in 9%. The knowledge of these hematological abnormalities associated with infantile visceral leishmaniasis can assist us in searching for Leishman bodies in the bone marrow smears to provide a diagnosis more quickly without necessarily resorting to more sophisticated tests., (Copyright © 2015 Elsevier Masson SAS. All rights reserved.)

Platelet satellitism is considered an uncommon phenomenon with an estimated frequency at 0.008%. About 100 cases have been published. If not recognized, this artifact can lead to an erroneous diagnosis of thrombocytopenia. We report the case of a patient, with cutaneous leishmaniasis, who developed an isolated thrombocytopenia. The blood smear prepared from peripheral blood sample collected with ethylenediaminetetraacetic acid showed platelets rosetting around polymorphonuclear. This phenomenon disappeared after treatment with Glucantime® for fifteen days and improvement of the lesions. We discuss also possible mechanisms to better understand this phenomenon.

Background: Permanent cardiac pacing remains the only effective treatment for chronic, symptomatic bradycardia. In recent years, the role of implantable pacing devices has expanded substantially., Aim: To compare the situation of patients with critical brady arrhythmias before and after pacing focusing on indication for pacemaker implantation, frequency of re intervention and early and late complications., Methods: Retrospective study performed over 24 years between 1984 and 2007 at the department of cardiology of Farhat Hached hospital. A total of 234 patients were included, and the database was formed by the patients' files and the protocols of implantation., Results: The mean age of patients was 69.5 years. The most frequently reported signs and symptoms before implantation of pace maker were dizzy spells and syncope respectively in 53% and 29.1% of patients. Among the electrocardiographic alterations leading to an indication of pacemaker implantation, atrio-ventricular blocks were the most numerous at 74.4% followed by sinus node disease at 17.1%. Early complications were represented essentially by haematoma and infection of the pocket of pacemaker respectively at 2.9% for each one. After a mean follow up of 6.8 years, 88 patients (45.3%) still free of symptoms. Late complications include lead dislodgement and pacemaker syndrome at 2% for each one., Conclusion: The results of our study demonstrates that even the rate of complications following pacemaker implantation is not high, the follow-up of patients should be fast, complete, safe, and clear, and should include sufficient documentation.

Introduction: Venous thromboembolic complications are well-known in patients with nephrotic syndrome. Arterial thrombosis has rarely been reported and is mainly observed in adults., Case Report: A 9-year-old patient with a history of steroid-dependent nephrotic syndrome was admitted after foot trauma. He presented with severe pain in his right foot, which was cold and mottled, with reduced sensation and motor activity. No pulse was palpable in his right foot. Doppler's ultrasonography confirmed the thrombosis of anterior and posterior tibial arteries in their distal portions. The patient received treatment with an arterial vasodilator and heparin, followed by antivitamin K therapy., Conclusion: Arterial thrombosis is a rare complication in children with nephrotic syndrome. It is presumably attributable to a hypercoagulable state and trauma., (Copyright © 2010 Elsevier Masson SAS. All rights reserved.)

The aim of this pilot study was to compare the effect of two different regimens of aspirin dosage on platelet of coronary artery disease (CAD) diabetic patients. Twenty-five CAD diabetic patients were included. Initially, all patients received aspirin 100 mg/day for 10 days. At day 10, aspirin antiplatelet effect was determined by measuring the collagen/epinephrine closure time (CT) 2 h after the last aspirin dosage and the next morning at 8 a.m.. The aspirin regimen was modified to 100 mg twice daily for patients showing a non-optimal platelet-inhibitory effect (CT < 298 s at 8 a.m.). Persistent high platelet reactivity (HPR) was defined by a CT < 160 s. During the 100 mg/day aspirin regimen, the prevalence of HPR at 8 a.m. was 48%, and only 7 patients (28%) had showed an optimal platelet-inhibitory effect. Bridging to the twice-daily regimen, the HPR was significantly reduced (p=0.025), and the optimal platelet-inhibitory effect was reached for 3 other patients. Our results showed that 100 mg aspirin twice-daily dosing rather than a once-daily dose significantly improves the aspirin effect on platelet of CAD diabetic patients. However, large prospective studies were needed to confirm whether this strategy will be clinically relevant and safe.

To date, the number of cases reported after exposure to mifepristone alone in early pregnancy is limited. In 24 cases, only 1 observation of fetal malformation associated with mifepristone has previously been reported. We report a case of amniotic band syndrome with limb amputation after exposure to mifepristone in early pregnancy. This association raises the question of a possible causal relationship.

Objective: To assess ultrasound findings of a fetus with intrauterine growth retardation (IUGR) and skin damage, related to intrauterine herpes simplex virus (HSV) infection., Methods: A 23-year-old, G1, P0 woman was referred at 23.5 weeks' gestation (WG) for IUGR. The patient had a previous single episode of serotype 1 herpes progenitalis at 11 WG. Ultrasound examination revealed extensive skin changes with no cerebral involvement. The methods employed for evaluation of the disease included maternal serology, amniocentesis and repeated ultrasound examinations., Results: Maternal serology was positive for HSV1 and fetal infection was confirmed via polymerase chain reaction (PCR). At 27 WG, amniotic fluid index decreased and lower limb skin as well as abdominal skin was irregular. Oesophagus was thickened. In contrast, upper limb skin and cranial vault were thin and less visible. IUGR was predominant as regards bone parameters. After termination of pregnancy, the fetus showed macroscopic characteristics of HSV infection. Microscopic examination revealed only placental and skin lesions., Conclusions: Our report illustrates a rare case of HSV1 intrauterine infection that occurred during the first trimester with bone and cephalic IUGR associated with extensive skin damage, and with no cerebral involvement., (Copyright 2006 John Wiley & Sons, Ltd.)