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991.
992.
M.C. Carvalho C. Pereira I.C. Gonalves H.M. Pinheiro A.R. Santos A. Lopes M.I. Ferra 《International biodeterioration & biodegradation》2008,62(2):96-103
Biodecolourisation of an azo dye by anaerobic cultures using a liposomal textile levelling agent as primary substrate was assessed. Liposomes seem to facilitate the uptake of the dye (Acid Orange 7) by anaerobic biomass, leading to a fast decolourisation (colour removal of 96% was achieved in the first sample port of the reactor profiles). On the other hand, the presence of dye (60–300 mg l−1) caused a decrease in the chemical oxygen demand (COD) degradation rate (4.1–2.5 g COD removed l−1 d−1 for 60 and 300 mg l−1 of dye, respectively), suggesting inhibitory effects.Aerobic degradation of aromatic amines was investigated in aerobic respirometric assays with different types of inocula. Sulfanilic acid and aniline were mineralised by inocula with a significant microbiological diversity, even with domestic effluent. These results were confirmed by a significant reduction of COD, total organic carbon (TOC) and a high oxygen consumption (biochemical oxygen demand/theoretical oxygen demand), 92±4%. Kinetic analysis showed that a sigmoid function describes quite well the experimental data, even better than the exponential model. Orthanilic and metanilic acids and 1-amino-2-naphtol were persistent under the tested conditions. 相似文献
993.
994.
Konstantin B Shumaev Andrey A Gubkin Vladimir A Serezhenkov Irina I Lobysheva Olga V Kosmachevskaya Enno K Ruuge Vadim Z Lankin Alexey F Topunov Anatoly F Vanin 《Nitric oxide》2008,18(1):37-46
Destructive effect of superoxide anions O2- derived from KO(2) or xanthine-xanthine oxidase system on dinitrosyl-iron complexes bound with bovine albumin or methemoglobin (DNIC-BSA or DNIC-MetHb) was demonstrated. The sensitivity of DNIC-BSA synthesized by the addition of DNIC with cysteine, thiosulfate or phosphate (DNIC-BSA-1, DNIC-BSA-2 or DNIC-BSA-3, respectively) to destructive action of O2- decreased in row: DNIC-BSA-1>DNIC-BSA-3>DNIC-BSA-2. The estimated rate constant for the reaction between O2- and DNIC-BSA-3 was equal to approximately 10(7)M(-1)s(-1). However, hydrogen peroxide and tert-butyl hydrogenperoxide (t-BOOH) did not induce any noticeable degradation of DNIC-BSA-3 even when used at concentrations exceeding by one order of magnitude those of the complex. As to their action on DNIC-MetHb both hydrogen peroxide and t-BOOH-induced rapid degradation of the complex. Both agents could induce the process due to the effect of alkylperoxyl or protein-derived free radicals formed at the interaction of the agents with ferri-heme groups of MetHb. Peroxynitrite (ONOO(-)) could also initiate protein-bound DNIC degradation more efficiently in the reaction with DNIC-BSA-3. Higher resistance of DNIC-MetHb to peroxynitrite was most probably due to the protective action of heme groups on ONOO(-). However, the analysis allows to suggest that the interaction of protein-bound DNICs with O2- is the only factor responsible for the degradation of the complexes in cells and tissues. 相似文献
995.
Lilia Dmitrieva Andrey A. Kondakov Eugeny Oleynikov Aidyn Kydyrmanov Kobey Karamendin Yesbol Kasimbekov Mirgaliy Baimukanov Susan Wilson Simon J. Goodman 《PloS one》2013,8(6)
The Caspian seal (Pusa caspica) has declined by more than 90% since 1900 and is listed as endangered by IUCN. We made the first quantitative assessment of Caspian seal by-catch mortality in fisheries in the north Caspian Sea by conducting semi-structured interviews in fishing communities along the coasts of Russia (Kalmykia, Dagestan), Kazakhstan and Turkmenistan. We recorded a documented minimum by-catch of 1,215 seals in the survey sample, for the 2008–2009 fishing season, 93% of which occurred in illegal sturgeon fisheries. Due to the illegal nature of the fishery, accurately quantifying total fishing effort is problematic and the survey sample could reflect less than 10% of poaching activity in the north Caspian Sea. Therefore total annual by-catch may be significantly greater than the minimum documented by the survey. The presence of high by-catch rates was supported independently by evidence of net entanglement from seal carcasses, during a mass stranding on the Kazakh coast in May 2009, where 30 of 312 carcasses were entangled in large mesh sturgeon net remnants. The documented minimum by-catch may account for 5 to 19% of annual pup production. Sturgeon poaching therefore not only represents a serious threat to Caspian sturgeon populations, but may also be having broader impacts on the Caspian Sea ecosystem by contributing to a decline in one of the ecosystem’s key predators. This study demonstrates the utility of interview-based approaches in providing rapid assessments of by-catch in illegal small-scale fisheries, which are not amenable to study by other methods. 相似文献
996.
997.
The acute adaptive immune response is complex, proceeding through phases of activation of quiescent lymphocytes, rapid expansion by cell division and cell differentiation, cessation of division and eventual death of greater than 95 % of the newly generated population. Control of the response is not central but appears to operate as a distributed process where global patterns reliably emerge as a result of collective behaviour of a large number of autonomous cells. In this review, we highlight evidence that competing intracellular timed processes underlie the distribution of individual fates and control cell proliferation, cessation and loss. These principles can be captured in a mathematical model to illustrate consistency with previously published experimentally observed data. 相似文献
998.
Summary Statistical properties of the ordinary least-squares (OLS), generalized least-squares (GLS), and minimum-evolution (ME) methods of phylogenetic inference were studied by considering the case of four DNA sequences. Analytical study has shown that all three methods are statistically consistent in the sense that as the number of nucleotides examined (m) increases they tend to choose the true tree as long as the evolutionary distances used are unbiased. When evolutionary distances (dij's) are large and sequences under study are not very long, however, the OLS criterion is often biased and may choose an incorrect tree more often than expected under random choice. It is also shown that the variance-covariance matrix of dij's becomes singular as dij's approach zero and thus the GLS may not be applicable when dij's are small. The ME method suffers from neither of these problems, and the ME criterion is statistically unbiased. Computer simulation has shown that the ME method is more efficient in obtaining the true tree than the OLS and GLS methods and that the OLS is more efficient than the GLS when dij's are small, but otherwise the GLS is more efficient.Offprint requests to: M. Nei 相似文献
999.
Background
The development of effective environmental shotgun sequence binning methods remains an ongoing challenge in algorithmic analysis of metagenomic data. While previous methods have focused primarily on supervised learning involving extrinsic data, a first-principles statistical model combined with a self-training fitting method has not yet been developed. 相似文献1000.
Soares Mayara Sandrielly Pereira Luduvico Karina Pereira Chaves Vitor Clasen Spohr Luiza Meine Bernardo de Moraes Lencina Claiton Leoneti Reginatto Flávio Henrique Spanevello Roselia Maria Simões Cláudia Maria Oliveira Stefanello Francieli Moro 《Neurochemical research》2021,46(5):1129-1140
Neurochemical Research - Neuroinflammation is an event that occurs in several pathologies of brain. Rubus sp. (blackberry) is a powerful antioxidant fruit, and its extract has neuroprotective... 相似文献