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991.
The construction of position dependent mass Scarf Hamiltonians of the trigonometric as well as the hyperbolic types is addressed by means of the factorization method and the Riccati equation. These Hamiltonians are shown to be independent of the ordering parameter of the kinetic term. Additionally, new families of Hamiltonians with the Scarf spectrum are also determined by supersymmetry. Some examples for masses with and without singularities are considered to illustrate our results. 相似文献
992.
Caroline Oliveira de Araújo Melo Thaís Cidália Vieira Marc Alexandre Duarte Gigonzac Jakeline Soares Fortes Sabrina Sara Moreira Duarte Aparecido Divino da Cruz Daniela de Melo e Silva 《Electrophoresis》2020,41(3-4):254-258
Alcohol use disorder (AUD) causes about 3.3 million deaths around the world each year. It is the primary risk factor for the global burden of diseases in American countries. Long-term abuse of alcohol induces numerous molecular and biochemical changes in tissues exposed to alcohol. The toxic effects of alcohol are mediated by DNA damage through various mechanisms, such as induction of oxidative damage, DNA adducts, crosslinks, and DNA strand breaks. The main aim of the current study was to compare the frequency of SNP polymorphisms in XRCC1 (rs7997782) and GSTP1 (rs1695) genes involved in DNA repair of single strand breaks (SSB) and xenobiotic detoxification between alcohol addicts and a control group comprised of non-drinkers. Genetic polymorphisms were identified following allelic specific PCR designed to generate the amplicons containing the variants. Then amplicons were sequenced, and sequences were aligned against the human genome reference deposited in GenBank using the CLC Sequence Viewer software (version 7.6.1). The GG homozygotes in rs1695 (GSTP1) were significantly (p = 0.023) 3.8x more frequent among those with AUD when compared to the control group. No SNP variation was observed in rs7997782 (XRCC1). rs1695 variant has been associated with susceptibility to various diseases, including those related to alcohol consumption. 相似文献
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995.
Cruz Neto J. X. Lopes J. O. Soubeyran A. Souza J. C. O. 《Annals of Operations Research》2022,316(2):1279-1300
Annals of Operations Research - In this paper, we consider an abstract regularized method with a skew-symmetric mapping as regularization for solving equilibrium problems. The regularized... 相似文献
996.
Bento G. C. Cruz Neto J. X. Meireles L. V. Soubeyran A. 《Annals of Operations Research》2022,316(2):1425-1443
Annals of Operations Research - In this paper we introduce a definition of approximate Pareto efficient solution as well as a necessary condition for such solutions in the multiobjective setting on... 相似文献
997.
Funnel-type ion tracks were produced in thin polymer foils by swift heavy ion irradiation and subsequent treatment with both low concentration etchants and acids from two different sides. The funnel shapes consist of shallow etched cones and residual latent tracks and thus combine both their characteristic properties, rectification and current spike emission, in one track each. Arrays of spike-emitting tracks are known to exhibit phase-locked synchronous electrical pulsations in accordance with the neural network theory. These pulsations were studied here on arrays of funnel-type tracks for the first time. As expected, the results strongly depend on the track density. In foils with low track densities, synchronous oscillations are rare and rather unstable events, whereas foils with high track densities exhibit stable, strong and long-lasting pulsations. Insertion of 0.1 M KCl solution into tracks at low density improved the shape and regularity of the spuriously occurring spikes somewhat, as compared with water in these tracks. 相似文献
998.
Jonathan Mbah Kiara Moorer Leonardo Pacheco‐Londoo Samuel Hernandez‐Rivera Gabriel Cruz 《Journal of Raman spectroscopy : JRS》2013,44(5):723-726
Incubator‐shaker method was used as a rapid technique to fabricate an efficient surface enhanced Raman scattering (SERS) substrate by combination of zero valent nanostructures and carbon fiber, which shows dramatic Raman enhancement of nitroaromatic molecule. The fabricated Ag nanoparticle on carbon‐fiber substrate (Ag–C) was used as an efficient SERS substrate to detect the adsorbed 2, 4‐dinitrotoluene molecules with a detection limit of 50 ppm. In advent, our developed SERS substrates could have great potential in detecting other nitro‐aromatic based‐explosive materials, such as 2, 4, 6‐trinitrotoluene molecules. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
999.
La-Scalea MA Chin CM Cruz ML Serrano SH Ferreira EI 《Bioelectrochemistry (Amsterdam, Netherlands)》2001,53(1):55-59
This paper describes the voltammetric behavior of primaquine as a previous support to the further understanding of the delivery and action mechanisms of its respective synthesized prodrugs. There are few papers describing the drug behavior and most of the time no correlation between oxidation process and pH is done. Our results showed that primaquine oxidation is a one-step reaction involving two electrons with the charge transfer process being strongly pH-dependent in acid medium and pH-independent in a weak basic medium, with the neutral form being easily oxidized. This leads to the conclusion that quinoline nitrogen ring neutralization is a determinant step to the formation of the oxidized primaquine form. The existence of a relationship between the primaquine dissociation equilibrium and its electrooxidation process is shown. This work points the importance of voltammetric methodology as a tool for further studies on quantitative relationship studies between chemical structure and biological activity (QSAR) for electroactive drugs. 相似文献
1000.
Kian A.R. Cruz J.B. Simaan M. A. 《Journal of Optimization Theory and Applications》2002,114(1):171-188
In this paper, we consider stochastic linear-quadratic discrete-time Nash games in which two players have access only to noise-corrupted output measurements. We assume that each player is constrained to use a linear Kalman filter-like state estimator to implement his optimal strategies. Two information structures available to the players in their state estimators are investigated. The first has access to one-step delayed output and a one-step delayed control input of the player. The second has access to the current output and a one-step delayed control input of the player. In both cases, statistics of the process and statistics of the measurements of each player are known to both players. A simple example of a two-zone energy trading system is considered to illustrate the developed Nash strategies. In this example, the Nash strategies are calculated for the two cases of unlimited and limited transmission capacity constraints. 相似文献