Deglaciation of the Edmundston Area and Reappraisal of Glacial Lake Madawaska Interpretation

Guidebook to the geology of Northeastern Maine and neighboring New Brunswick: The 72nd annual meeting of the New England Intercollegiate Geological Conference, Presque Isle, Maine, October 10-13, 1980: Trip B-

Evaluation of a TiO2 photocatalysis treatment on nitrophenols and nitramines contaminated plant wastewaters by solid-phase extraction coupled with ESI HPLC–MS

Nitration reactions of aromatic compounds are commonly involved in different industrial processes for pharmaceutical, pesticide or military uses. For many years, most of the manufacturing sites used lagooning systems to treat their process effluents. In view of a photocatalytic degradation assay, the wastewater of a lagoon was investigated by using HPLC coupled with mass spectrometry. The wastewater was highly concentrated in RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine), HMX (octahydro- 1,3,5,7-tetranitro-1,3,5,7-tetrazocine) and two herbicides Dinoterb (2-tert-butyl-4,6-dinitrophenol) and Dinoseb (2-sec-butyl-4,6-dinitrophenol). First of all, an analytical method using solid-phase extraction (SPE) combined with HPLC ESI MS/MS was put in work for identification and titration of RDX, HMX and the two dinitrophenols in a complex natural matrix. Then, the UV/TiO2 treatment was investigated for pollutants removal. Dinitrophenolic compoundswere significantly degraded after a 8-h-exposition of the wastewater/TiO2 suspension, whereas RDX and HMX were poorly affected

Microbial population changes during bioremediation of nitroaromatic - and nitramine-contaminated lagoon

Nitration reactions of aromatic compounds are commonly involved in military industrial processes. Military industries treated their process effluents using lagoon systems for many years. In this study, the sediment of a lagoon was investigated from a bioremediation objective. The physico-chemical characterization of the sediments showed the organic nature of the sediment (25.4% carbon with a C:N ¼ 3) highly concentrated in RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine), HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine) as well as two herbicides Dinoterb (2-tert-butyl-4,6-dinitrophenol) and Dinoseb (2-sec-butyl-4,6-dinitrophenol). Analysis of the 16S rRNA gene clone library revealed the presence of three dominant families, Geobacteriacea, Clostridiaceae and Pseudomonaceae. A bioremediation assay was carried out in anaerobic conditions in order to degrade organic compounds. In these conditions, 100% of Dinoterb and Dinoseb were degraded after 75 days of culture, while RDX and HMX were not consumed. The 16S rRNA gene clone library analysis of this incubation showed a drastic reduction of the final biodiversity composed by clones related to Enterobacteriaceae (especially Leclercia adecarboxylata) and Pseudomonaceae family. It was then suggested that Enterobacteriaceae and Pseudomonaceae were potentially involved in biodegradation of these two herbicides. To confirm this hypothesis, cultures were carried out with isolated species of Pseudomonas putida, Pseudomonas citronellolis and L. adecarboxylata in the presence of Dinoterb. The data confirmed that in the presence of glucose, these microorganisms are able to consume Dinoterb

Cardiogenic shock and nutrition: safe?

Cardiogenic shock is a common diagnosis in patients in the intensive care unit (ICU), and is characterized by a decreased cardiac output in the presence of adequate intravascular volume associated with an inadequate tissue perfusion including a physiological reduction in the splanchnic territory. It may occur in isolation as a reflection of cardiac pathology, or it may be part of a shock syndrome involving other pathogenic mechanisms. As the use of enteral nutrition (EN) is associated with an increase in mesenteric arterial output, EN could be deleterious by overwhelming the mechanisms of mesenteric adaptation. Accordingly, EN has been suspected to increase the risk of mesenteric ischaemia, bacterial translocation and sepsis in ICU patients with cardiogenic shock. International guidelines recommend a cautious use of EN within 72h following cardiogenic shock. Recent evidence indicates that mesenteric arterial output may decrease during parenteral nutrition administration, suggesting that parenteral nutrition could have a protective effect on splanchnic organs in ICU patients with cardiogenic shock. Contrary to former beliefs, several meta-analyses have shown that parenteral nutrition is not associated with increased mortality. Exclusive EN is associated with negative energy balance and the combination of EN with supplemental parenteral nutrition during the first days following ICU admission has been proposed to prevent negative energy balance. Such a nutritional strategy could also be beneficial for the mesenteric circulation in cardiogenic shock, and consequently may improve the clinical outcome of patients with cardiogenic shock. Clinical trials are warranted to verify these hypothese

Catalytic methylation of aromatic amines with formic acid as the unique carbon and hydrogen source

International audienceA novel methodology is presented for the direct methylation of amines, using formic acid as a unique source of carbon and hydrogen. Based on ruthenium(II) catalysts, the formation of the N-CH3 group proceeds via an efficient formylation/transfer hydrogenation pathwa

Nitrite complexes of the rare earth elements

International audienceThe coordination chemistry of the nitrite anion has been investigated with rare earth elements, and the resulting complexes were structurally characterized. Among them, the first homoleptic examples of nitrite complexes of samarium, ytterbium and yttrium are described. The coordination behavior of the nitrite ion is directly controlled by the ionic radius of the metal cation. While the nitrito ligand is stable in the coordination sphere of cerium(III), it is readily reduced by SmI2

A Blind Beam Tracking Scheme for Millimeter Wave Systems

Millimeter-wave is one of the technologies powering the new generation of wireless communication systems. To compensate the high path-loss, millimeter-wave devices need to use highly directional antennas. Consequently, beam misalignment causes strong performance degradation reducing the link throughput or even provoking a complete outage. Conventional solutions, e.g. IEEE 802.11ad, propose the usage of additional training sequences to track beam misalignment. These methods however introduce significant overhead especially in dynamic scenarios. In this paper we propose a beamforming scheme that can reduce this overhead. First, we propose an algorithm to design a codebook suitable for mobile scenarios. Secondly, we propose a blind beam tracking algorithm based on particle filter, which describes the angular position of the devices with a posterior density function constructed by particles. The proposed scheme reduces by more than 80% the overhead caused by additional training sequences.Comment: 6 pages, 7 figure