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91.
92.
Letizia Modeo Giovanna Rosati Ilaria Andreoli Simone Gabrielli Franco Verni Giulio Petroni 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2006,82(9):359-374
In the present paper we redescribe the ciliate Chattonidium setense Villeneuve 1937 combining morphological observations (live, stained, scanning, and transmission electron microscope) with behavioral notes and molecular data. Ultrastructural analysis revealed remarkable similarities between Chattonidium and representative members of the class Heterotrichea in cortical structure and cytoplasmic organization. The most similar genus for these aspects appears to be Condylostoma. To verify this relatedness, 18S rRNA genes from Chattonidium and from one Condylostoma species were sequenced. Phylogenetic analysis indicates Chattonidium belongs to the class Heterotrichea defined according to the modern taxonomy, and confirms its relatedness with Condylostoma already hypothesized by Villeneuve-Brachon (1940). The presence of the aboral cavity complex, a unique feature never described in other ciliates, and its peculiar organization revealed by ultrastructural analysis fully justify, in our opinion, the maintenance of Chattonidium in the separate family Chattonidiidae, established by Villeneuve-Brachon in 1940. 相似文献
93.
Error growth in the numerical integration of periodic orbits by multistep methods, with application to reversible systems 总被引:4,自引:0,他引:4
We study the growth with time of (the coefficients of the asymptoticexpansion of) the error in the numerical integration with linearmultistep methods of periodic solutions of systems of ordinarydifferential equations. Particular attention is devoted to reversiblesystems. It turns out that symmetric linear multistep methodscannot be recommended in spite of the fact that they mimic thereversibility of the true flow. For reversible second-ordersystems, linear multistep methods without parasitic double rootsare useful. 相似文献
94.
We describe a simple method to measure the top quark mass in the
channel that may be useful in Run II of D? detector. The method is validated by applying it to the Run Ib eμ data. 相似文献
95.
JM Chatterjee M Saha Sarkar S Bhattacharya P Banerjee S Sarkar RP Singh S Murulithar RK Bhowmik 《Pramana》2001,57(1):165-169
High-spin states of 95,97Mo (Z=42, N=53,55) nuclei have been investigated through 82Se(18O, xn) reaction at Eb=60 MeV. The level scheme in 95Mo has been observed upto ≏ 10 MeV in the present experiment. The level structure shows mainly single particle character.
In 97Mo, the ground state level sequence has been extended to ≏ 4.5 MeV while the previous information had been up to 2.4 MeV.
A negative parity band built on 1437 keV (11/2−) excited state has been extended to 5.5 MeV. The structure seems to show a coexistence of single particle and collective
modes of excitation. Properties of both the nuclei have been compared with shell model calculations using OXBASH. 相似文献
96.
Background
Clinical spinal cord injury in domestic dogs provides a model population in which to test the efficacy of putative therapeutic interventions for human spinal cord injury. To achieve this potential a robust method of functional analysis is required so that statistical comparison of numerical data derived from treated and control animals can be achieved. 相似文献97.
Bruno Gabriel Lucca Jacqueline Marques Petroni Valdir Souza Ferreira 《International journal of environmental analytical chemistry》2018,98(9):859-873
We report in this work, for the first time, the voltammetric study and the development of an electroanalytical method for the determination of sodium diethyldithiocarbamate (Na-DDC) using solid amalgam electrode fabricated with silver nanoparticles. The experimental parameters were studied and the best voltammetric response was reached when using 0.02 mol L–1 Britton–Robinson buffer (pH = 5.5). Cyclic voltammograms of the substance presented two voltammetric signals: one cathodic peak at Ep = – 0.55 V and one anodic peak at Ep = – 0.49 V. The redox process of Na-DDC showed itself as an adsorption-controlled and quasi-reversible system. A mechanism for this electrochemical reaction was proposed. The analytical studies employed square-wave adsorptive stripping voltammetry (SWAdSV) and were based on the cathodic signal given by Na-DDC. Good linearity was observed in the concentration range from 2.83 × 10–7 mol L–1 to 6.89 × 10–6 mol L–1. The obtained limit of detection was 7.26 × 10–8 mol L–1. The electroanalytical approach described here was successfully employed for the determination of Na-DDC in river water at levels of concentration from 1.46 × 10–7 mol L–1 to 1.46 × 10–6 mol L–1 with good repeatability and reproducibility (RSD values of 4.2% and 5.9%, respectively). The values found during these determinations presented good concordance when compared with the expected values. According to the data presented here, the solid amalgam electrode fabricated with silver nanoparticles may be seen as an effective and green tool for the electrochemical analysis of Na-DDC and also other reducible compounds that usually require mercury-based electrode surfaces. 相似文献
98.
Statistical analysis of financial data mostly focused on testing the validity of Brownian motion (Bm). Analyses performed on several time series have shown deviation from the Bm hypothesis, that is at the base of the evaluation of many financial derivatives. We analyze the behavior of performance measures based on maximum drawdown movements (MDD(T)), testing their stability when the underlying process deviates from the Bm hypothesis. In particular we consider the fractional Brownian motion (fBm), and fluctuations estimated empirically on raw market data. The case study of the rising part of speculative bubbles is reported. 相似文献
99.
Fabrício RS Pereira Andréa Alessio Maurício S Sercheli Tatiane Pedro Elizabeth Bilevicius Jane M Rondina Helka FB Ozelo Gabriela Castellano Roberto JM Covolan Benito P Damasceno Fernando Cendes 《BMC neuroscience》2010,11(1):1-13