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21.
Pierron F Baudrimont M Gonzalez P Bourdineaud JP Elie P Massabuau JC 《Environmental science & technology》2007,41(8):3005-3011
European eel (Anguilla anguilla) populations are in decline. Glass eel recruitment has fallen 10-fold since the early 1980s. Estuaries play a fundamental role in the life history of eels because glass eels must pass through them to reach freshwater ecosystems. Unfortunately, because of their geographical position at the upstream basin slopes, estuaries accumulate metals like cadmium and are important sites of hypoxia events. In this context, we studied the effect of the oxygen level on the ventilation of the glass eel. In parallel, glass eels were submitted to different dissolved cadmium concentrations (0, 2, and 10 microg L(-1)) under two oxygen levels (normoxia PO2 = 21 kPa and Hypoxia PO2 = 6 kPa). The expression level of various genes involved in the mitochondrial respiratory chain, in the cellular response to metal and oxidative stresses, was investigated. Our results showed that hypoxia enhances (1) ventilation of the postlarval stage and (2) Cd accumulation in gills only at the lowest metal water concentration tested (2 microg Cd L(-1)). At the gene level, Cd exposure mimics the effect of hypoxia since we observed a decrease in expression of genes involved in the respiratory chain and in the defense against oxidative stress. 相似文献
22.
Single crystals and nonlinear process for outstanding vibration-powered electrical generators 总被引:1,自引:0,他引:1
Badel A Benayad A Lefeuvre E Lebrun L Richard C Guyomar D 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2006,53(4):673-684
This paper compares the performances of vibration-powered electrical generators using a piezoelectric ceramic and a piezoelectric single crystal associated to several power conditioning circuits. A new approach of the piezoelectric power conversion based on a nonlinear voltage processing is presented, leading to three novel high performance power conditioning interfaces. Theoretical predictions and experimental results show that the nonlinear processing technique may increase the power harvested by a factor of 8 compared to standard techniques. Moreover, it is shown that, for a given energy harvesting technique, generators using single crystals deliver 20 times more power than generators using piezoelectric ceramics. 相似文献
23.
Elie Fereche Itoba-Tombo Seteno Karabo Obed Ntwampe Jonathan James Andrew Bell John Baptist Nzukizi Mudumbi Tolbert Mhlangabezi Golela 《The International journal of environmental studies》2017,74(1):28-41
In recent years, developing countries have increased their cassava (Manihot esculenta) production for food security. Cassava contains cyanogen glycosides, mainly as linamarin, which through bio-catalysis, i.e. enzyme hydrolysis, results in hydrogen cyanide (HCN). HCN is released into the environment through numerous ways with subsequent volatilisation. Thus, the HCN released during the period 2002–2013 was estimated between 0.025?×?10?3 to 6.71 ppq (African), 0.012?×?10?3 to 1.01 ppq (Asian) and 0.007?×?10?3 to 0.920?×?10?3 ppq (South American). Furthermore, a decade’s (2014–2024) projection of HCN volatilisation displays increases of 60.5% (Africa), 57.7% (Asia) and 50.5% (South America) when compared with the current production. Furthermore, gas released during cassava plants’ growth, i.e. HCN, NH3, and NO2, was quantified in healthy plants. Varying concentrations of HCN were released. These further indicated the presence of a pseudo-halogenic gas in the environment – a contributor to climate change. 相似文献
24.
Elie H. Sarraf Ankit Kansal Mrigank Sharma Edmond Cretu 《Journal of Electronic Testing》2012,28(5):599-614
We propose a novel adaptive technique based on pseudo-random (PN) sequences for self-calibration and self-testing of MEMS-based inertial sensors (accelerometers and gyroscopes). The method relies on using a parameterized behavioral model implemented on FPGA, whose parameters values are adaptively tuned, based on the response to test pseudo-random actuation of the physical structure. Dedicated comb drives actuate the movable mass with binary maximum length pseudo-random sequences of small amplitude, to keep the device within the linear operating regime. The frequency of the stimulus is chosen within the mechanical spectral operating range of the micro-device, such that the induced response leads to the identification of the mechanical transfer function, and to the tuning of the associated digital behavioral model. In case of a micro-gyroscope, experimental results demonstrate the adaptive tracking of the damping coefficient from 5.57?×?10?5? Kg/s to 7.12?×?10?5? Kg/s and of the stiffness coefficient from 132?N/m to 137.7?N/m. In the case of a MEMS accelerometer, the damping and stiffness coefficients are correctly tracked from 3.4?×?10?3? Kg/s and 49.56?N/m to 4.57?×?10?3? Kg/s and 51.48?N/m, respectively—the former values are designer-specified target values, while the latter are experimentally measured parameters for fabricated devices operating in a real environment. Hardware resources estimation confirms the small area the proposed algorithm occupies on the targeted FPGA device. 相似文献
25.
Nono Jean Hubert ;Bikele Mama Desire ;Ghogomu Numbonui Julius ;Younang Elie ;Mbaze Meva'a Luc Leonard ;Lissouck Daniel ;Zobo Mfomo Joseph ;Shridhar Ramchandra Gadre 《化学与化工:英文版》2014,(12):1109-1124
In this article, we have performed B3LYP/6-31+G(d) calculations of geometrical and reaction enthalpies of antioxidant mechanisms for ADPHT 1-4 (3-alkyl-4-phenylacetylamino-lH-1,2,4-triazol-5-ones) and its derivatives: HAT (hydrogen atom transfer), SET-PT (single electron transfer-proton transfer) and SPLET (sequential proton-loss electron transfer) were investigated in gas and solution-phases. Solvent contribution to enthalpies was computed employing integral equation formalism IEF-PCM (integral equation formalism method) method. It turned out that the lowest BDEs (bond dissociation energies) is obtained for C-H bonds due to captodative effect in various media. Results indicate that HAT mechanism represents the most anticipated process in gas-phase from thermodynamic point of view. But, the SPLET represents the thermodynamically preferred reaction pathway in solvents (2-propanol, acetonitrile, DMF (N,N-dimethylformamide) and water). The authors showed that bond dissociation energies, IP (ionization potential) and PA (proton affinity) are sufficient to evaluate the thermodynamically preferred mechanism. 相似文献
26.
27.
Deli Markusse Nguimbou Richard Marcel Njantou Baudelaire Elie Njintang Yanou Nicolas Scher Joël Mbofung Carl Moses 《Food science and biotechnology》2020,29(12):1741-1753
Food Science and Biotechnology - Sun-dried calyxes of Hibiscus sabdariffa were finely grinded and fractionated by controlled differential sieving processing (CDSp) into four granulometric classes.... 相似文献
28.
Pauline Spolaore Claire Joannis‐Cassan Elie Duran Arsne Isambert 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2006,81(6):1049-1056
Optimization of Nannochloropsis oculata growth was undertaken using the response surface method. A central composite design was defined to study the effects of temperature, pH, incident light intensity and aeration rate on the maximum growth rate of the microalga. Using statistical analysis, the first model calculated to fit results was twice improved. The final model obtained was used to clarify the effects of each factor and their interactions on the growth of Nannochloropsis oculata. The optimum growth conditions of this microorganism were also estimated as 21 °C, 52 µmol photons m?2 s?1, pH 8.4 and 14.7 VVH of aeration rate. These conditions were tested and validated experimentally since the maximum growth rate achieved with these parameters, 0.0359 h?1, is the best reported in this study. Copyright © 2006 Society of Chemical Industry 相似文献
29.
The purpose of this paper was to contribute to a new conceptual understanding of delirium by reviewing evidence related to its prevention, treatment, and outcome. The review process involved a systematic search of the literature on each topic, assessment of the validity of the studies retrieved, and examination of their results. The literature search identified 10 studies on prevention, 13 studies on treatment, and 15 studies on outcome. Most studies had methodological limitations. Abroad spectrum of interventions appeared to be modestly effective in preventing delirium in young and old surgical patients but not elderly medical patients; systematic detection and intervention programs and special nursing care appeared to add large benefits to traditional medical care in young and old surgical patients and modest benefits in elderly medical patients; haloperidol, chlorpromazine, and mianserin appeared to be useful in controlling the symptoms of delirium in both surgical and medical patients; and good levels of premorbid function seemed to be related to better outcomes. Although the above findings do not contribute to a new conceptual understanding of delirium, they do suggest directions for further research on the treatment of delirium. 相似文献
30.
Baba A. Rivaldo Kpadonou Bruno Barbier Joost Wellens Elie Sauret B. V. C. Adolphe Zangré 《国际水》2013,38(7):1021-1039
A spatial hydroeconomic model was developed to analyze the competition between small private (SPIS) and large public (LPIS) irrigation systems for water control in tropical watersheds and applied to several water allocation policies in Kou watershed in Burkina Faso. Capital (cash and motorpumps) is the main constraining factor for SPIS expansion, and capital inflow accelerates SPIS development and reduces water flows for downstream LPIS users. As SPIS is more cost-effective and less water thirsty, LPIS needs to shift to less water-demanding and high-value crops or adopt more water-saving practices. Otherwise, only a sharp rice yield increase in LPIS can justify a reserved water quota for downstream users. 相似文献