The effects of ondansetron versus dexamethasone on electrocardiographic markers of ventricular repolarization in children undergoing cochlear implant

Introduction: Congenital hearing loss is associated with cardiac rhythm disturbances namely long Q-T syndrome. This study was designed to investigate the effect of anti-emetic doses of ondansetron and dexamethasone on ECG recordings in children undergoing cochlear implant surgery. Methods: Sixty-three pediatric patients scheduled for elective cochlear implantation were enrolled in the study. Two patients were excluded as their baseline ECG showed long QT syndrome. Anesthesia was induced with fentanyl, propofol and atracurium and maintained with propofol. Dexamethasone 0.1 mg.kg�1or ondansetron 0.2 mg.kg�1was randomly administered for the participants approximately 30 min before the end of surgery. ECG recording was performed 15 min after induction of anesthesia and 15 min after dexamethasone/ondansetron administration. RR interval, QRS duration, QT interval, and Tp-e interval were measured by a blinded cardiologist. Results: Ondansetron resulted in no significant changes in RR, JTc and QTc intervals; while prolongedTp-e interval. Multivariable logistic regression analysis showed that use of ondansetron was an independent predictor of QTc prolongation after adjustment for age, gender and baseline QTc (OR = 17.94, CI 95 1.97�168.70, p = 0.011). The incidence of postoperative retching/vomiting in ondansetron group was significantly lower than dexamethasone group. (3.2 vs. 26.7, p = 0.011). Conclusion: The risk of arrhythmias with the use of ondansetron in otherwise healthy candidates of cochlear implant is very low. However, the drug may induce significant changes in ECG parameters. The clinical significance of these changes in patients with cardiac conduction abnormalities should be investigated in further studies. © 2020 Elsevier B.V

Relationship between maximum clot firmness in ROTEM® and postoperative bleeding after coronary artery bypass graft surgery in patients using clopidogrel

Background: The aim of the present study was to investigate the relationship between maximum clot firmness (MCF) in rotational thromboelastometry (ROTEM®) and postoperative bleeding in patients on clopidogrel after emergency coronary artery bypass graft surgery (CABG). Methods: This observational study recruited 60 patients posted for emergency CABG following unsuccessful primary percutaneous coronary intervention (PCI) while on 600 mg of clopidogrel. The study population was divided into 2 groups on the basis of their MCF in the extrinsically activated thromboelastometric (EXTEM) component of the (preoperative) ROTEM® test: patients with MCF <50 mm (n = 16) and those with MCF �50 mm (n = 44). Postoperative chest tube drainage amount, need for blood product transfusion, postoperative complications, and duration of mechanical ventilation after CABG were recorded. Results: No significant differences were observed between the two groups regarding duration of surgery, cardiopulmonary bypass, and aortic cross-clamp time. Chest tube drainage at 6, 12, and 24 h after Intensive Care Unit admission were significantly higher in the patients with MCF below 50 mm. The need for blood product transfusion was higher in the group with MCF <50 mm. In patients who experienced postoperative bleeding of 1000 mL or more, the ROTEM® parameters of INTEM (Intrinsically activated thromboelastomery) and MCF, EXTEM and MCF, and HEPTEM (INTEM assay performed in the presence of heparinase) MCF (but not FIBTEM (Thromboelastometric assay for the fibrin part of the clot) values) were significantly lower than those with postoperative bleeding <1000 mL (P � 0.05). Conclusions: When platelet aggregometry is not available, the ROTEM® test could be useful for the prediction of increased risk bleeding after emergency CABG in patients who have received a loading dose of clopidogrel. © 2018 Annals of Cardiac Anaesthesia | Published by Wolters Kluwer - Medknow

FeCoCp3 Molecular Magnets as Spin Filters

Metallorganic molecules have been proposed as excellent spin filters in molecular spintronics because of the large spin-polarization of their electronic structure. However, most of the studies involving spin transport, have disregarded fundamental aspects such as the magnetic anisotropy of the molecule and the excitation of spin-flip processes during electron transport. Here, we study a molecule containing a Co and an Fe atoms stacked between three cyclopentadienyl rings that presents a large magnetic anisotropy and a S=1. These figures are superior to other molecules with the same transition metal, and improves the spin-filtering capacities of the molecule. Non-equilibrium Green's functions calculations based on density functional theory predict excellent spin-filtering properties both in tunnel and contact transport regimes. However, exciting the first magnetic state drastically reduces the current's spin polarization. Furthermore, a difference of temperature between electrodes leads to strong thermoelectric effects that also suppress spin polarization. Our study shows that in-principle good molecular candidates for spintronics need to be confronted with inelastic and thermoelectric effects

FLICK: Developing and running application-specific network services

Data centre networks are increasingly programmable, with $\textit{application-specific}$ network services proliferating, from custom load-balancers to middleboxes providing caching and aggregation. Developers must currently implement these services using traditional low-level APIs, which neither support natural operations on application data nor provide efficient performance isolation. We describe FLICK, a framework for the programming and execution of application-specific network services on multi-core CPUs. Developers write network services in the FLICK $\textit{language}$, which offers high-level processing constructs and application-relevant data types. FLICK programs are translated automatically to efficient, parallel $\textit{task graphs}$, implemented in C++ on top of a user-space TCP stack. Task graphs have bounded resource usage at runtime, which means that the graphs of multiple services can execute concurrently without interference using cooperative scheduling. We evaluate FLICK with several services (an HTTP load-balancer, a Memcached router and a Hadoop data aggregator), showing that it achieves good performance while reducing development effort.Engineering and Physical Sciences Research CouncilThis is the author accepted manuscript. The final version is available from USENIX via https://www.usenix.org/conference/atc16/technical-sessions/presentation/ali

Towards refining the classification of glass trade beads imported into Southern Africa from the 8th to the 16th century AD

Tracing the origin of glass trade beads excavated at archaeological sites can contribute significantly to dating a site and reconstructing prehistoric trade routes. Wood developed a temporally sensitive bead sequence dating from the 8th to the 16th century AD for beads excavated at southern African sites that is commonly used by archaeologists to classify beads according to their morphology. In this study we develop a multidisciplinary methodology to refine the classification of glass beads based on morphology alone. Glass trade beads excavated at 11 sites along the upper reaches of the Limpopo River in east-central Botswana are used as case study. The beads were visually classified according to their morphological properties (colour, size, etc.) and analysed with Raman spectroscopy and portable X-ray fluorescence (XRF). Energy Dispersive Spectroscopy (EDS) of one bead showed that two types of glass were sintered together to form a recycled product, explaining the divergence of Raman spectra recorded on different zones. The study confirms the value of a morphological classification based on existing data sets as a first approach, but demonstrates that both Raman and XRF measurements can contribute to a more exact classification of glass beads imported into southern Africa from the East before the 17th century AD.Farahnaz Koleini and Linda C. Prinsloo acknowledge the financial contribution from the National Research Foundation (NRF) of South Africa and Philippe Colomban from EGIDE PROTEA.http://www.journals.elsevier.com//journal-of-cultural-heritage2017-05-31hb2016Anthropology and ArchaeologyPhysic

Assessment of Muscular Activity by Mechanomyogram(MMG)

Background and aims   Recordings of electrical activity in the muscle and surface electromyography (EMG) have been widely used in the field of applied physiology. In parallel to  recording of the EMG, the detectable low-frequency vibration signal generated by the skeletal  muscle has been known and well documented. As the nature of the signal has been progressively   revealed, the term of mechanomyography (MMG) has been proposed by a recent review. The  main mechanism of the MMG generation has been considered to be sound pressure waves due to  the dimensional changes, i.e., lateral expansion of the activated muscle fibres.   Methods   Low-frequency vibrations produced by muscle fibres are clearly distinguishable from  the EMG, because MMG and EMG exhibit differences in response latency, spike duration, and  frequency. During voluntary contraction at constant force the MMG frequency content does not   change significantly.   Results   This suggests that the frequency of MMG signal is directly related to the absolute force level of the muscle, irrespective of fatigue phenomena. At low force contractions, in contrast to   EMG signal, the changes in the amplitude content of the MMG are more consistent with muscle  fatigue. This indicated that the amplitude of MMG signal might be recommended as a method to  improve the objective and reliable detection of muscle fatigue induced by low force contraction.   Conclusion   MMG is most likely a valuable supplement to EMG as a non-invasive method to  examine various aspects of muscle function including fatigue, electromechanical delay, muscle fibre type patterns, age related changes in muscular performance, muscle atrophy, and neuromuscular performance

Towards refining the classification of glass trade beads imported into Southern Africa from the 8th to the 16th century AD

Tracing the origin of glass trade beads excavated at archaeological sites can contribute significantly to dating a site and reconstructing prehistoric trade routes. Wood developed a temporally sensitive bead sequence dating from the 8th to the 16th century AD for beads excavated at southern African sites that is commonly used by archaeologists to classify beads according to their morphology. In this study, we develop a multidisciplinary methodology to refine the classification of glass beads based on morphology alone. Glass trade beads excavated at 11 sites along the upper reaches of the Limpopo River in east-central Botswana are used as case study. The beads were visually classified according to their morphological properties (colour, size, etc.) and analysed with Raman spectroscopy and portable X-ray fluorescence (XRF). Energy Dispersive Spectroscopy (EDS) of one bead showed that two types of glass were sintered together to form a recycled product, explaining the divergence of Raman spectra recorded on different zones. The study confirms the value of a morphological classification based on existing data sets as a first approach, but demonstrates that both Raman and XRF measurements can contribute to a more exact classification of glass beads imported into southern Africa from the East before the 17th century AD

Unravelling the glass trade bead sequence from Magoro Hill, South Africa: separating pre-seventeenth-century Asian imports from later European counterparts

Excavations conducted between 2010 and 2012 at Magoro Hill, a site in South Africa\u27s Limpopo Province frequented or intermittently occupied by African farming communities since the first millennium AD, yielded a substantial glass bead assemblage. A selection of the beads was studied non-destructively by classifying them according to morphological attributes, supplemented by Raman analyses and XRF measurements. It became evident that a morphological classification of beads recovered from sites that include imports into Africa after the seventeenth century AD could be problematic due to apparent morphological similarities between earlier and later beads. This paper demonstrates the use and archaeological application of Raman and XRF measurements to separate earlier imported beads from later counterparts by identifying glass nanostructure, as well as pigments and opacifiers, which were not used in bead series pre-dating the seventeenth century AD. Results obtained from Raman and XRF measurements indicate that although some beads retrieved from Magoro Hill pre-date the seventeenth century and belong to the Indo-Pacific (K2, East Coast, Khami) and Zimbabwe series, the largest number of beads is from a later European origin. This ties in with the settlement history of the site, which suggests that it primarily served as a rendezvous for episodic rainmaking rituals before it became the stronghold and capital of a Venda chiefdom, headed by the Magoro dynasty, in the second half of the eighteenth century AD. The comparative analysis of the long bead sequence sheds new light on changing patterns in the availability, range, consumption and origin of glass trade beads imported into the northern interior of South Africa over a period of about 1000years. Graphical abstract GRAPHICAL ABSTRACT CAPTIO