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Lesesve J.-F.,University of Lorraine | Lesesve J.-F.,Science Academy | El Adssi H.,University of Lorraine | Watine J.,Service de Biologie Polyvalente | And 5 more authors.
International Journal of Laboratory Hematology | Year: 2013

Introduction: The schistocytes are fragmented red blood cells mainly observed in the setting of hemolytic anemias where they remain an important criterion for the diagnosis. As the identification of these cells is still problematic, the International Council for Standardization in Hematology (ICSH) set up a consensus report in November, 2011. The French Group of Cellular Hematology (GFHC) aimed to collect the opinion of French biologists directly confronted to schistocytes measurements, about these guidelines. Methods: Among the 578 professionals, 169 (29%) answered to the 10 questions dealing with the identification and measurements of schistocytes as proposed by the ICSH. Results: A consensus was reached for the urgent need of such guidelines documents, especially in the current background of the European accreditation EN ISO 15189 rules. A traduction in native (French) language was warmly wished in order to facilitate the diffusion of the information. The pathologic threshold for the diagnosis of thrombotic microangiopathic anemia (TMA) (>1%) remained questionable. For half of the biologists, the new fragmented red blood cell (FRC) parameter recently provided by two manufacturers of automated blood cell counters was still doubtfull for routine use. Conclusion: This survey assessed the impact of international 'guidelines' on the French biological community. The will to implement validated recommendations was strong, reflecting the awareness of the biologists to standardize the laboratory investigations. © 2013 John Wiley & Sons Ltd.

News Article
Site: www.nature.com

When he labelled outspoken academics as terrorists, Turkey’s increasingly authoritarian President Recep Tayyip Erdoğan was probably not thinking of Voltaire’s eighteenth-century philosophical maxim: “To hold a pen is to be at war”. Erdoğan sent shivers down the spines of those who care about human rights by declaring on 14 March that those who support terrorists are as guilty as those “who pull the trigger”, and that Turkish law should be changed to reflect this. “The fact that an individual is a deputy, an academic, an author, a journalist or the director of an NGO does not change the fact that that person is a terrorist,” he said. One the same day, three academics from universities in Istanbul were hauled into police custody and then refused bail while prosecutors considered charges of making propaganda for a terrorist organization. Their crime? In January, they had signed a petition that called for an end to violence in the southeast of the country, where government forces have been fighting Kurdish separatists. The petition was signed by 1,128 academics, mostly from Turkish universities, when it was publicly launched on 11 January. It immediately sparked Erdoğan’s rage. Many politically appointed university rectors leapt into line, launching disciplinary investigations into members of their staff who had signed — more than 500 so far. Dozens of signatories were brought in for police questioning. The harsh response attracted a shocked solidarity. Another 1,000 people signed the petition, including a large number of Western scientists, before it was closed on 20 January. An atmosphere of uncertainty and fear prevails. None of the signatories knows whether they, too, will be arrested, and several have had death threats. Some have actively sought sabbaticals abroad; those working outside the country are afraid to return even to visit family. Meanwhile, Turkey is playing a major part on the world political stage, in a role that is overshadowing the fate of the academics. Turkey is a geopolitical fulcrum. On one side it borders war-torn Middle East, on the other, strife-ridden Europe that is struggling to cope with the refugee crisis. When the country reached a historic agreement with the European Union last week to take back migrants who were crossing into Europe illegally, many in the EU complained bitterly about making a deal with Erdoğan because of his worrying human-rights record. Terrorist attacks in Turkey are intensifying, some carried out by Kurdish separatists, others by the Islamist group ISIS. Erdoğan’s controversial announcement followed on the heels of a deadly attack in Ankara, and on 19 March, a suicide bomber killed four in Istanbul. Kurdish separatist terrorism had abated during a two-year ceasefire, but that broke down last July. Erdoğan argues that the peace petition, by focusing only on government military attacks on Kurdish militants, which have killed many innocent civilians, and ignoring terrorist attacks and other serious human-rights abuses carried out by the separatists, actively supports terrorism. While appreciating the urgency of a call to peace, many scientists and academics themselves have reservations about the petition, seeing it as unhelpfully confrontational and even intellectually dishonest. But many have still bravely spoken up for the freedom of expression of the signatories. Turkey’s recently formed Science Academy published a strongly supportive statement in January. “The right to express one’s opinions — even if these might be annoying or minority views — is an essential freedom of every citizen and every academic,” it said. The academy should know — it was created by those who resigned en masse from the Turkish Academy of Sciences when Erdoğan took it over by decree in 2011. Scientists everywhere should use their pens and send their support.

Dedeoglu B.,Bogazici University | Monari A.,University of Lorraine | Monari A.,French National Center for Scientific Research | Etienne T.,University of Lorraine | And 5 more authors.
Journal of Physical Chemistry C | Year: 2014

Poly(silafluorene-phenylenedivinylene)s and poly((tetraphenyl)-silole- phenylenedivinylene)s are promising materials to be used as chemical sensors for explosives detection. The optoelectronic properties of these polymers as well as their constituent units have been investigated by modeling the properties of their excited states. Natural Transition Orbital analysis and topological φS descriptor assessment have been used to qualitatively and quantitatively characterize the physical nature of the transitions constituting the absorption spectra. The main transitions observed in all oligomers are associated to be a π-π∗ transition of the bridging moiety. Lower energy transitions of charge transfer character are further considered to understand the fluorescence quenching mechanism upon the complexation of these polymers with the analytes. Indeed the charge-transfer character of the first excited state leads to the emergence of thermal deactivation channels and hence to luminescence quenching. © 2014 American Chemical Society.

Katipoglu-Yazan T.,Technical University of Istanbul | Pala-Ozkok I.,Technical University of Istanbul | Ubay-Cokgor E.,Technical University of Istanbul | Orhon D.,Technical University of Istanbul | Orhon D.,Science Academy
Bioresource Technology | Year: 2013

The study evaluated acute impact of erythromycin and tetracycline on nitrification and organic carbon removal kinetics in mixed microbial culture. Acclimated biomass was obtained from a fill and draw reactor fed with peptone mixture selected as synthetic substrate and operated at a sludge age of 10. days. Acute inhibition was tested in batch reactors involving a control unit started solely with substrate and the others with additional doses of each antibiotic. Modeling indicated that both steps of nitrification were totally blocked by erythromycin. Tetracycline inhibited and retarded nitrification kinetics at 50. mg/L and stopped nitrite oxidation at 200. mg/L, leading to nitrite accumulation. Both antibiotics also affected organic carbon removal by inducing partial inactivation of the heterotrophic community in the culture, increased substrate storage and accelerated endogenous respiration, with a relatively slight impact on heterotrophic growth. Major inhibitory effect was on process stoichiometry, leading to partial utilization of organic substrate. © 2013 Elsevier Ltd.

Kim H.,University of Tennessee at Knoxville | Helmbrecht E.E.,University of Tennessee at Knoxville | Blaine Stalans M.,University of Tennessee at Knoxville | Schmitt C.,University of Tennessee at Knoxville | And 4 more authors.
Plant Physiology | Year: 2011

Ethylene influences many processes in Arabidopsis (Arabidopsis thaliana) through the action of five receptor isoforms. We used high-resolution, time-lapse imaging of dark-grown Arabidopsis seedlings to better understand the roles of each isoform in the regulation of growth in air, ethylene-stimulated nutations, and growth recovery after ethylene removal. We found that ETHYLENE RECEPTOR1 (ETR1) is both necessary and sufficient for nutations. Transgene constructs in which the ETR1 promoter was used to drive expression of cDNAs for each of the five receptor isoforms were transferred into etr1-6;etr2-3;ein4-4 triple loss-of-function mutants that have constitutive growth inhibition in air, fail to nutate in ethylene, and take longer to recover a normal growth rate when ethylene is removed. The patterns of rescue show that ETR1, ETR2, and ETHYLENE INSENSITIVE4 (EIN4) have the prominent roles in rapid growth recovery after removal of ethylene whereas ETR1 was the sole isoform that rescued nutations. ETR1 histidine kinase activity and phosphotransfer through the receiver domain are not required to rescue nutations. However, REVERSION TO SENSITIVITY1 modulates ethylene-stimulated nutations but does not modulate the rate of growth recovery after ethylene removal. Several chimeric receptor transgene constructs where domains of EIN4 were swapped into ETR1 were also introduced into the triple mutant. The pattern of phenotype rescue by the chimeric receptors used in this study supports a model where a receptor with a receiver domain is required for normal growth recovery and that nutations specifically require the full-length ETR1 receptor. © 2011 American Society of Plant Biologists.

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