Phosphorylation of Sli15 by Ipl1 is important for proper CPC localization and chromosome stability in <em>Saccharomyces cerevisiae</em>

The chromosomal passenger complex (CPC) is a key regulator of eukaryotic cell division, consisting of the protein kinase Aurora B/Ipl1 in association with its activator (INCENP/Sli15) and two additional proteins (Survivin/Bir1 and Borealin/Nbl1). Here we have identified multiple sites of CPC autophosphorylation on yeast Sli15 that are located within its central microtubule-binding domain and examined the functional significance of their phosphorylation by Ipl1 through mutation of these sites, either to non-phosphorylatable alanine (sli15-20A) or to acidic residues to mimic constitutive phosphorylation (sli15-20D). Both mutant sli15 alleles confer chromosome instability, but this is mediated neither by changes in the capacity of Sli15 to activate Ipl1 kinase nor by decreased efficiency of chromosome biorientation, a key process in cell division that requires CPC function. Instead, we find that mimicking constitutive phosphorylation of Sli15 on the Ipl1 phosphorylation sites causes delocalization of the CPC in metaphase, whereas blocking phosphorylation of Sli15 on the Ipl1 sites drives excessive localization of Sli15 to the mitotic spindle in pre-anaphase cells. Consistent with these results, direct interaction of Sli15 with microtubules in vitro is greatly reduced either following phosphorylation by Ipl1 or when constitutive phosphorylation at the Ipl1-dependent phosphorylation sites is mimicked by aspartate or glutamate substitutions. Furthermore, we find that mimicking Ipl1 phosphorylation of Sli15 interferes with the 'tension checkpoint'--the CPC-dependent mechanism through which cells activate the spindle assembly checkpoint to delay anaphase in the absence of tension on kinetochore-microtubule attachments. Ipl1-dependent phosphorylation of Sli15 therefore inhibits its association with microtubules both in vivo and in vitro and may negatively regulate the tension checkpoint mechanism

Time Reversal to Localise Multiple Partial Discharges in Power Cables

The paper studies the suitability of the electromagnetic time reversal (EMTR) technique to localise multiple sources of partial discharges (PD) in power cables. In particular, the localisation of two PDs in a homogeneous power line is investigated both in the presence or absence of noise. The investigation, which is based on numerical simulations, shows that an EMTR-based PD localisation method is able to localise two PDs occurring simultaneously in a line using only a measurement at one observation point (OP), indiscriminately collecting the direct and reflected signals coming from the two PD sources. The EMTR procedure to localise multiple PD sources, using a Transmission Line Matrix model digital twin for the time reversal simulations, is described and the challenges that must be addressed to develop an EMTR-based device for the on-line location of multiple PDs are discussed

Electromagnetic time reversal applied to online partial discharge location in power cables: influence of interfering reflections from the cable circuit

In online single-sided partial discharge (PD) location settings, PD reflection patterns are affected by all components present in the cable circuit. This paper describes the performance of electromagnetic time reversal (EMTR) when interfering reflections contribute to the transient waveforms emitted by the PD. The analysed situation refers to a ring main unit (RMU) in the medium voltage (MV) grid where PD recordings are disturbed by signals reflected from the other cables connected to the RMU, potentially affecting the PD location accuracy. We show that the accuracy of EMTRbased location methods is unaffected by such effects

Adverse drug events associated with vitamin K antagonists: factors of therapeutic imbalance

Nancy El-Helou, Amal Al-Hajje, Rola Ajrouche, Sanaa Awada, Samar Rachidi, Salam Zein, Pascale SalamehClinical and Epidemiological Research Laboratory, Faculty of Pharmacy, Lebanese University, Beirut, LebanonBackground: Adverse drug events (ADE) occur frequently during treatment with vitamin K antagonists (AVK) and contribute to increase hemorrhagic risks.Methods: A retrospective study was conducted over a period of 2 years. Patients treated with AVK and admitted to the emergency room of a tertiary care hospital in Beirut were included. The aim of the study was to identify ADE characterized by a high international normalized ratio (INR) and to determine the predictive factors responsible for these events. Statistical analysis was performed with the SPSS statistical package.Results: We included 148 patients. Sixty-seven patients (47.3%) with an INR above the therapeutic range were identified as cases. The control group consisted of 81 patients (54.7%) with an INR within the therapeutic range. Hemorrhagic complications were observed in 53.7% of cases versus 6.2% of controls (P &amp;lt; 0.0001). No significant difference was noticed between cases and controls regarding the indication and the dose of AVK. Patients aged over 75 years were more likely to present an INR above the therapeutic range (58.2%, P = 0.049). Recent infection was present in 40.3% of cases versus 6.2% of controls (P &amp;lt; 0.0001) and hypoalbuminemia in 37.3% of cases versus 6.1% of controls (P &amp;lt; 0.0001). Treatment with antibiotics, amiodarone, and anti-inflammatory drugs were also factors of imbalance (P &amp;lt; 0.0001).Conclusion: Many factors may be associated with ADE related to AVK. Monitoring of INR and its stabilization in the therapeutic range are important for preventing these events.Keywords: adverse drug events, vitamin K antagonists, bleeding risks, therapeutic imbalanc

Electromagnetic fields associated with the M‐component mode of charge transfer

In upward flashes, charge transfer to ground largely takes place during the initial continuous current (ICC) and its superimposed pulses (ICC pulses). ICC pulses can be associated with either M-component or leader/return‐stroke‐like modes of charge transfer to ground. In the latter case, the downward leader/return stroke process is believed to take place in a decayed branch or a newly created channel connected to the ICC‐carrying channel at relatively short distance from the tower top, resulting in the so‐called mixed mode of charge transfer to ground. In this paper, we study the electromagnetic fields associated with the M‐component charge transfer mode using simultaneous records of electric fields and currents associated with upward flashes initiated from the Säntis Tower. The effect of the mountainous terrain on the propagation of electromagnetic fields associated with theM‐component charge transfer mode (including classical M‐component pulses and M‐component‐type pulses superimposed on the initial continuous current) is analyzed and compared with its effect on the fields associated with the return stroke (occurring after the extinction of the ICC) and mixed charge transfer modes. For the analysis, we use a 2‐Dimentional Finite‐Difference Time Domain method, in which the M‐component is modeled by the superposition of a downward current wave and an upward current wave resulting from the reflection at the bottom of the lightning channel (Rakov et al., 1995, https://doi.org/10.1029/95JD01924 model) and the return stroke and mixed mode are modeled adopting the MTLE (Modified Transmission Line with Exponential Current Decay with Height) model. The finite ground conductivity and the mountainous propagation terrain between the Säntis Tower and the field sensor located 15 km away at Herisau are taken into account. The effects of the mountainous path on the electromagnetic fields are examined for classical M‐component and M‐component‐type ICC pulses. Use is made of the propagation factors defined as the ratio of the electric or magnetic field peak evaluated along the mountainous terrain to the field peak evaluated for a flat terrain. The velocity of theM‐component pulse is found to have a significant effect on the risetime of the electromagnetic fields. A faster traveling wave speed results in larger peaks for the magnetic field. However, the peak of the electric field appears to be insensitive to the M‐component wave speed. This can be explained by the fact that at 15 km, the electric field is still dominated by the static component, which mainly depends on the overall transferred charge. The contribution of the radiation component to the M‐component fields at 100 km accounts for about 77% of the peak electric field and 81% of the peak magnetic field, considerably lower compared to the contribution of the radiation component to the return stroke fields at the same distance. The simulation results show that neither the electric nor the magnetic field propagation factors are very sensitive to the risetimes of the current pulses. However, the results indicate a high variability of the propagation factors as a function of the branch‐to‐channel junction point height. For junction point heights of about 1 km, the propagation factors reach a value of about 1.6 for the E‐field and 1.9 for the H‐field. For a junction height greater than 6 km, the E‐field factor becomes slightly lower than 1. The obtained results are consistent with the findings of Li, Azadifar, Rachidi, Rubinstein, Paolone, et al. (2016, https://doi.org/10.1109/TEMC.2015.2483018) in which an electric field propagation factor of 1.8 was inferred for return strokes and mixed‐mode pulses, considering that junction points lower than 1 km or so would result in a mixed mode of charge transfer, in which a downward leader/return‐stroke‐like process is believed to take place. It is also found that the field enhancement (propagation factor) for return stroke mode is higher for larger ground conductivities. Furthermore, the enhancement effect tends to decrease with increasing current risetime, except for very short risetimes (less than 2.5 μs or so) for which the tendency reverses. Finally, model‐predicted fields associated with different charge transfer modes, namely, return stroke, mixed‐mode, classical M‐component, and M‐component‐type ICC pulse are compared with experimental observations at the Säntis Tower. It is found that the vertical electric field waveforms computed considering the mountainous terrain are in very good agreement with the observed data. The adopted parameters of the models that provide the best match with the measured field waveforms were consistent with observations. The values for the current decay height constant adopted in the return stroke and mixed‐mode models (1.0 km for the return stroke and 0.8 km for the mixed‐mode pulse) are lower than the value of 2.0 km typically used in the literature

Associated factors for maternal-foetal complications in pregnant women with sickle cell disease at the departmental University Hospital of Borgou and Alibori (Benin)

Background: Sickle cell disease is one of the most common genetic disorders in the world, with a high prevalence in Africa. It is a pathology that threatens the maternal-fetal prognosis in case of pregnancy. The objective of this study was to describe the maternal-foetal complications and to identify the factors associated with maternal-foetal complications in sickle cell pregnant women (SP).Methods: This was a descriptive cross-sectional study with retrospective data collection over a period of 4 years (01 January 2015 to 31 August 2019). The study population was All SP who had given birth in the maternity ward of the UH of Borgou/Alibori.Results: We recorded 130 SP out of 10087 admissions, either a frequency of 1.3%. There were 119/130 exploitable files. Maternal complications during pregnancy were: vaso-occlusive crises 79%; severe anaemia 27.7%; hyponatremia 10.1%; vasculo-renal syndromes 18.4%; infections 74.8%. The foetal complications during pregnancy were: Preterm births 38.6%, in utero deaths 17.6%, low birth weight 54.7%. Early neonatal mortality was 8.4% (8/95). There was a 4.2% (5/119) of maternal deaths. Low educational level of the SP, SS genotype, insufficient antenatal follow-up and antenatal follow-up outside the specialized center for the care of sickle cell pregnant women (SCCSP) were the factors associated with maternal-foetal complications in the SP.Conclusions: The association of pregnancy and sickle cell disease is frequent in West Africa, particularly in Benin, and is characterised by numerous maternal-foetal complications that are associated with certain factors

LMA observation of upward flashes at Säntis Tower: preliminary result

Lightning striking tall towers is mainly of the upward lightning type, which is characterized by the absence of a first return stroke and the presence of an initial continuous current (ICC) with or without superimposed pulses. The Säntis Tower is 124 m tall and it is located on the top of the Säntis Mountain (2502 m ASL) in the eastern Swiss Alps. The Tower location exhibited the highest lightning flash density in Switzerland during the period from 1999 to 2006. The Tower was instrumented in May 2010 for the measurement of lightning current parameters. In order to complement these data, a Lightning Mapping Array (LMA) was deployed around the Tower during the Summer 2017. The LMA system locates the sources of radio emissions in the very high frequency range (VHF, 60-66 MHz) in three dimensions by a time-of-arrival analysis. The LMA system allows detailed analysis of individual flashes, through the mapping of the lightning channels in the cloud with sufficient time resolution and spatial precision to locate the origin and propagation of each flash. With the help of the LMA, we intend to further investigate the initiation and propagation characteristics of upward lightning emerging from the Tower. From June 29 to August 15, 2017, 33 upward flashes initiated from the Säntis tower were registered by the LMA network. These records are the first set of VHF total lightning mapping obtained in Switzerland. Preliminary results of the campaign are presented in this paper. © 2018 IEEE.Peer ReviewedPostprint (published version

Dosage des HAP dans les produits de pêche par GC-MS au niveau des côtes marocaines

Being widespread and highly likely to cause adverse biological effects, PAHs have been the subject of several studies and evaluation. Polycyclic aromatic hydrocarbons (PAHs) are a series of hydrocarbons with the carbon atoms are arranged in benzene cycles united to each other, they pose a significant toxicological risk even at low concentrations, related especially to their carcinogenic and/or mutagenic properties. In addition, PAHs are part of some biodegradable contaminants which makes them persistent in natural environments. Thus, their fate in the environment has become a concern. For humans, the majority source of exposure to PAHs for non-smokers is the ingestion of food (meat, fish, vegetables, etc.). This study is conducted on fishery products collected along the Moroccan coast, landed at the level of the main ports of the Kingdom. Analyses of mean concentrations of PAHs in local products vary significantly according to the sites (p < 0,05). The results show a satisfactory quality of these products for consumption. The sampling sites are selected so as to diagnose the state of organic contamination in various fishing products. The determination of these pollutants is done by gas chromatography coupled to mass spectrometry.Les HAP étant largement répandus et fortement susceptibles d’entraîner des effets biologiques néfastes, ils ont fait l’objet de plusieurs études et évaluations. Les Hydrocarbure Aromatique Polycyclique (HAP) sont une série d'hydrocarbures dont les atomes de carbone sont disposés en cycles benzéniques unis les uns aux autres. Ils présentent un risque toxicologique important même à de faibles concentrations, liés surtout à leurs propriétés cancérigènes et/ou mutagènes. De plus, les HAP font partie des contaminants peu biodégradables ce qui les rend persistants dans les milieux naturels. Ainsi, leur sort dans l'environnement est devenu un sujet préoccupant. Pour l'homme, la source majoritaire d'exposition aux HAP pour les non fumeurs est l'ingestion des denrées alimentaires (viandes, poissons, légumes, etc..). Cette étude est menée sur les produits de pêche prélevés le long  du littoral marocain, débarqués au niveau des principaux ports du royaume. Les analyses des teneurs moyennes des HAP dans les produits locaux variaient significativement selon les sites (p<0,05). Les résultats montrent une qualité satisfaisante de ces  produits pour la consommation. Les sites des prélèvements sont choisis de manière à diagnostiquer l’état de la contamination organique dans les différents produits pêchés. Le dosage de ces polluants est réalisé par chromatographie gazeuse couplée à la spectrométrie de masse