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151.
152.
Josette Garnier Aurélie Cébron Gaëlle Tallec Gilles Billen Mathieu Sebilo Anun Martinez 《Biogeochemistry》2006,77(3):305-326
The Seine River estuary (France) is the receptacle of a drainage basin characterised by high population density, heavy industrial
activity and intensive agriculture. Whereas nitrate concentrations are high due to diffuse sources in the upstream drainage
basin, ammonium mainly originates from the effluents of the Achères wastewater treatment plant (WWTP) downstream from Paris
and its suburbs (6.5 million equivalent-inhabitants). Ammonium is mostly nitrified in the tidal freshwater estuary and nitrification
causes a strong summer oxygen deficit. Average longitudinal summer profiles of oxygen and nitrogen concentrations for two
periods, between 1993–1997 and 1998–2003 in dry hydrological conditions (excluding the wet years 2000 and 2001) clearly reflect
the changes due to the improved treatment of wastewater from Paris and its suburbs. On the basis of daily water flux data
and twice monthly nitrogen measurements at the boundaries of the upstream freshwater estuarine section (108 km), we calculated
nitrification and denitrification fluxes, whose annual averages were 43 and 71 × 103 kg N d−1 respectively from 1993 to 2003, with summer values (July–September) representing 73 and 57% of the annual fluxes, respectively.
The degree of denitrification in the upper estuary appears to be closely related to the nitrification, itself more loosely
related to the amount of reduced nitrogen (Kjeldahl) brought by the treated effluents from the Achères WWTP. We estimated
the total N2O emissions to about 40 kg N d−1 (25–60 kg N d−1) in the same sector. 相似文献
153.
154.
Sizulu Moyo Helen S. Cox Jennifer Hughes Johnny Daniels Leigh Synman Virginia De Azevedo Amir Shroufi Vivian Cox Gilles van Cutsem 《PloS one》2015,10(3)
Background
A community based drug resistant tuberculosis (DR-TB) program has been incrementally implemented in Khayelitsha, a high HIV and TB burden community in South Africa. We investigated loss from treatment (LFT), and post treatment outcomes of DR-TB patients in this setting.Methodology
LFT, defined as interruption of treatment for ≥2 consecutive months was assessed among patients initiating DR-TB treatment for the first time between January 2009 and July 2011. Patients were traced through routine data sources to identify those who subsequently restarted treatment and those who died. Additional information on patient status and survival after LTF was obtained from community DR-TB counselors and from the national death registry. Post treatment outcomes were observed until July 2013.Results
Among 452 patients initiating treatment for the first time within the given period, 30% (136) were LFT, with 67% retention at 18 months. Treatment was restarted in 27 (20%) patients, with additional resistance recorded in 2/25 (8%), excluding two with presumed DR-TB. Overall, 34 (25%) patients died, including 11 who restarted treatment. Males and those in the age category 15-25 years had a greater hazard of LFT; HR 1.93 (95% CI 1.35-2.75), and 2.43 (95% CI 1.52-3.88) respectively. Older age (>35 years) was associated with a greater hazard of death; HR 3.74 (1.13- 12.37) post treatment. Overall two-year survival was 62%. It was lower (45%) in older patients, and was 92% among those who received >12 months treatment.Conclusion
LFT was high, occurred throughout the treatment period and was particularly high among males and those aged 15-25 years. Overall long term survival was poor. High rates of LFT should however not preclude scale up of community based care given its impact in increasing access to treatment. Further research is needed to support retention of DR-TB patients on treatment, even within community based treatment programs. 相似文献155.
Gaëtan Podevijn Rehan O’Grady Nithin Mathews Audrey Gilles Carole Fantini-Hauwel Marco Dorigo 《Swarm Intelligence》2016,10(3):193-210
We study the psychophysiological state of humans when exposed to robot groups of varying sizes. In our experiments, 24 participants are exposed sequentially to groups of robots made up of 1, 3 and 24 robots. We measure both objective physiological metrics (skin conductance level and heart rate), and subjective self-reported metrics (from a psychological questionnaire). These measures allow us to analyse the psychophysiological state (stress, anxiety, happiness) of our participants. Our results show that the number of robots to which a human is exposed has a significant impact on the psychophysiological state of the human and that higher numbers of robots provoke a stronger response. 相似文献
156.
Sven H. Hausner David Alagille Andrei O. Koren Louis Amici Julie K. Staley Kelly P. Cosgrove Ronald M. Baldwin Gilles D. Tamagnan 《Bioorganic & medicinal chemistry letters》2009,19(2):543-545
A series of novel 5- and 6-substituted 2-(4-dimethylaminophenyl)-1,3-benzoxazoles was synthesized and their potential as imaging probes for Alzheimer’s Disease (AD)-related amyloid plaque was evaluated in vitro and in vivo. In vitro binding affinities for Aβ1–40 peptide of several of these compounds were in the low-nanomolar range . The lowest Ki of 9.3 nM was found for N-(2-(4-(dimethylamino)phenyl)-1,3-benzoxazol-5-yl)-4-iodobenzamide (1e). Its 123I-radiolabeled form ([123I]1e) was subsequently prepared by iododestannylation of the corresponding tributylstannyl precursor and evaluated in vivo in a baboon model using SPECT imaging. Contrary to our expectations, 1e did not cross the blood–brain barrier (BBB) to any significant extent. 相似文献
157.
Dongjing Zhang Rosemary Susan Lees Zhiyong Xi Jeremie R. L. Gilles Kostas Bourtzis 《PloS one》2015,10(8)
Due to the absence of a perfect method for mosquito sex separation, the combination of the sterile insect technique and the incompatible insect technique is now being considered as a potentially effective method to control Aedes albopictus. In this present study first we examine the minimum pupal irradiation dose required to induce complete sterility in Wolbachia triple-infected (HC), double-infected (GUA) and uninfected (GT) female Ae. albopictus. The HC line is a candidate for Ae. albopictus population suppression programmes, but due to the risk of population replacement which characterizes this triple infected line, the individuals to be released need to be additionally irradiated. After determining the minimum irradiation dose required for complete female sterility, we test whether sterilization is sufficient to prevent invasion of the triple infection from the HC females into double-infected (GUA) populations. Our results indicate that irradiated Ae. albopictus HC, GUA and GT strain females have decreased fecundity and egg hatch rate when irradiated, inversely proportional to the dose, and the complete sterilization of females can be acquired by pupal irradiation with doses above 28 Gy. PCR-based analysis of F1 and F2 progeny indicate that the irradiated HC females, cannot spread the new Wolbachia wPip strain into a small cage GUA population, released at a 1:5 ratio. Considering the above results, we conclude that irradiation can be used to reduce the risk of population replacement caused by an unintentional release of Wolbachia triple-infected Ae. albopictus HC strain females during male release for population suppression. 相似文献
158.
Serena Ciarroni Lorenzo Gallipoli Maria C. Taratufolo Margi I. Butler Russell T. M. Poulter Christine Pourcel Gilles Vergnaud Giorgio M. Balestra Angelo Mazzaglia 《PloS one》2015,10(8)
The bacterial canker of kiwifruit by Pseudomonas syringae pv. actinidiae is an emblematic example of a catastrophic disease of fruit crops. In 2008 a new, extremely virulent form of the pathogen emerged and rapidly devastated many Actinidia spp. orchards all over the world. In order to understand differences in populations within this pathovar and to elucidate their diffusion and movements on world scale, it is necessary to be able to quickly and on a routine basis compare new isolates with previous records. In this report a worldwide collection of 142 strains was analyzed by MLVA, chosen as investigative technique for its efficacy, reproducibility, simplicity and low cost. A panel of 13 Variable Number of Tandem Repeats (VNTR) loci was identified and used to describe the pathogen population. The MLVA clustering is highly congruent with the population structure as previously established by other molecular approaches including whole genome sequencing and correlates with geographic origin, time of isolation and virulence. For convenience, we divided the VNTR loci in two panels. Panel 1 assay, using six loci, recognizes 23 different haplotypes, clustered into ten complexes with highest congruence with previous classifications. Panel 2, with seven VNTR loci, provides discriminatory power. Using the total set of 13 VNTR loci, 58 haplotypes can be distinguished. The recent hypervirulent type shows very limited diversity and includes, beside the strains from Europe, New Zealand and Chile, a few strains from Shaanxi, China. A broad genetic variability is observed in China, but different types are also retrievable in Japan and Korea. The low virulent strains cluster together and are very different from the other MLVA genotypes. Data were used to generate a public database in MLVAbank. MLVA represents a very promising first-line assay for large-scale routine genotyping, prior to whole genome sequencing of only the most relevant samples. 相似文献
159.
160.
Competitive exclusion of diarrheagenic Escherichia coli (ETEC) from human enterocyte-like Caco-2 cells by heat-killed Lactobacillus 总被引:7,自引:0,他引:7
Gilles Chauvière Marie-Hélène Coconnier Sophie Kerneis Arlette Darfeuille-Michaud Bernard Joly Alain L. Servin 《FEMS microbiology letters》1992,91(3):213-217
Diarrheagenic Escherichia coli (ETEC) bearing CFA/I or CFA/II adhesive factors specifically adhere onto the brush border of the polarized epithelial human intestinal Caco-2 cells in culture. Heat-killed Lactobacillus acidophilus strain LB, that adheres onto Caco-2 cells, inhibits diarrheagenic Escherichia coli adhesion in a concentration-dependent manner. Since the L. acidophilus does not express ETEC-CFA adhesive factors, it can be postulated that the heat-killed L. acidophilus LB cells inhibit diarrheagenic E. coli attachment by steric hindrance of the human enterocytic ETEC receptors. 相似文献