Relations among several nuclear and electronic density functional reactivity indexes

A set of connections among several nuclear and electronic indexes of reactivity in the framework of the conceptual Density Functional Theory by using an expansion ofthe energy functional in terms of the total number of electrons and the normal coordinates within a canonical ensemble was derived. The relations obtained provided explicit links between important quantities related to the chemical reactivity of a system. This paper particularly demonstrates that the derivative of the electronic energy with respect to the external potential of a system in its equilibrium geometry was equal to the negative of the nuclear repulsion derivative with respect to the external potential

Electronic couplings and on-site energies for hole transfer in DNA: systematic quantum mechanical/molecular dynamic study

The electron hole transfer (HT) properties of DNA are substantially affected by thermal fluctuations of the π stack structure. Depending on the mutual position of neighboring nucleobases, electronic coupling V may change by several orders of magnitude. In the present paper, we report the results of systematic QM/molecular dynamic (MD) calculations of the electronic couplings and on-site energies for the hole transfer. Based on 15 ns MD trajectories for several DNA oligomers, we calculate the average coupling squares 〈 V2 〉 and the energies of basepair triplets X G+ Y and X A+ Y, where X, Y=G, A, T, and C. For each of the 32 systems, 15 000 conformations separated by 1 ps are considered. The three-state generalized Mulliken-Hush method is used to derive electronic couplings for HT between neighboring basepairs. The adiabatic energies and dipole moment matrix elements are computed within the INDO/S method. We compare the rms values of V with the couplings estimated for the idealized B -DNA structure and show that in several important cases the couplings calculated for the idealized B -DNA structure are considerably underestimated. The rms values for intrastrand couplings G-G, A-A, G-A, and A-G are found to be similar, ∼0.07 eV, while the interstrand couplings are quite different. The energies of hole states G+ and A+ in the stack depend on the nature of the neighboring pairs. The X G+ Y are by 0.5 eV more stable than X A+ Y. The thermal fluctuations of the DNA structure facilitate the HT process from guanine to adenine. The tabulated couplings and on-site energies can be used as reference parameters in theoretical and computational studies of HT processes in DNA

Estimation of electronic coupling in π -stacked donor-bridge-acceptor systems: correction of the two-state model

Comparison of donor-acceptor electronic couplings calculated within two-state and three-state models suggests that the two-state treatment can provide unreliable estimates of Vda because of neglecting the multistate effects. We show that in most cases accurate values of the electronic coupling in a π stack, where donor and acceptor are separated by a bridging unit, can be obtained as Ṽ da = (E2 - E1) μ12 Rda + (2 E3 - E1 - E2) 2 μ13 μ23 Rda2, where E1, E2, and E3 are adiabatic energies of the ground, charge-transfer, and bridge states, respectively, μij is the transition dipole moments between the states i and j, and Rda is the distance between the planes of donor and acceptor. In this expression based on the generalized Mulliken-Hush approach, the first term corresponds to the coupling derived within a two-state model, whereas the second term is the superexchange correction accounting for the bridge effect. The formula is extended to bridges consisting of several subunits. The influence of the donor-acceptor energy mismatch on the excess charge distribution, adiabatic dipole and transition moments, and electronic couplings is examined. A diagnostic is developed to determine whether the two-state approach can be applied. Based on numerical results, we showed that the superexchange correction considerably improves estimates of the donor-acceptor coupling derived within a two-state approach. In most cases when the two-state scheme fails, the formula gives reliable results which are in good agreement (within 5%) with the data of the three-state generalized Mulliken-Hush model

Estimates of electronic coupling for excess electron transfer in DNA

Electronic coupling Vda is one of the key parameters that determine the rate of charge transfer through DNA. While there have been several computational studies of Vda for hole transfer, estimates of electronic couplings for excess electron transfer (ET) in DNA remain unavailable. In the paper, an efficient strategy is established for calculating the ET matrix elements between base pairs in a π stack. Two approaches are considered. First, we employ the diabatic-state (DS) method in which donor and acceptor are represented with radical anions of the canonical base pairs adenine-thymine (AT) and guanine-cytosine (GC). In this approach, similar values of Vda are obtained with the standard 6-31 G* and extended 6-31++ G* basis sets. Second, the electronic couplings are derived from lowest unoccupied molecular orbitals (LUMOs) of neutral systems by using the generalized Mulliken-Hush or fragment charge methods. Because the radical-anion states of AT and GC are well reproduced by LUMOs of the neutral base pairs calculated without diffuse functions, the estimated values of Vda are in good agreement with the couplings obtained for radical-anion states using the DS method. However, when the calculation of a neutral stack is carried out with diffuse functions, LUMOs of the system exhibit the dipole-bound character and cannot be used for estimating electronic couplings. Our calculations suggest that the ET matrix elements Vda for models containing intrastrand thymine and cytosine bases are essentially larger than the couplings in complexes with interstrand pyrimidine bases. The matrix elements for excess electron transfer are found to be considerably smaller than the corresponding values for hole transfer and to be very responsive to structural changes in a DNA stack

Electronic and vibrational contributions to first hyperpolarizability of donor-acceptor-substituted azobenzene

In this study we report on the electronic and vibrational (hyper)polarizabilities of donor–acceptorsubstituted azobenzene. It is observed that both electronic and vibrational contributions to the electricdipole first hyperpolarizability of investigated photoactive molecule substantially depend on the conformation. The contributions to the nuclear relaxation first hyperpolarizability are found to be quite important in the case of two considered isomers (cis and trans). Although the double-harmonic term is found to be the largest in terms of magnitude, it is shown that the total value of the nuclear relaxation contribution to vibrational first hyperpolarizability is a result of subtle interplay of higher-order contributions. As a part of the study, we also assess the performance of long-range-corrected densityfunctional theory in determining vibrational contributions to electric dipole (hyper)polarizabilities. In most cases, the applied long-range-corrected exchange correlation potentials amend the drawbacks of their conventional counterparts

La scena nel testo: Enrico IV di Luigi Pirandello

The starting point is the understanding of the dramatic text as literary text, thus it could be analyzed with methodologies coming from literary studies: the dramatic text is literature, creation of language and it can be read and interpreted as such. Of course I acknowledge the text’s performativity, implicit in its characteristic and functions. The analysis of Enrico IV (1921) constitutes a practical application of the proposal and the opportunity for opening the discussion to new perspectives.

Applying recommendations to aligncompetences, methodology and assessment in Telematics, Computing and Electronic Engineering courses

The alignment between competences, teaching-learning methodologies and assessment is a key element of the European Higher Education Area. This paper presents the efforts carried out by six Telematics, Computer Science and Electronic Engineering Education teachers towards achieving this alignment in their subjects. In a joint work with pedagogues, a set of recommended actions were identified. A selection of these actions were applied and evaluated in the six subjects. The cross-analysis of the results indicate that the actions allow students to better understand the methodologies and assessment planned for the subjects, facilitate (self-) regulation and increase students’ involvement in the subjects.

Early postnatal hospital discharge: the consequences of reducing length of stay for women and newborns

The objective of this study is to examine the literature and identify most salient outcomes of early postnatal discharge for women, newborns and the health system. An electronic search strategy was designed including the following sources: Web of Science, Scopus, ProQuest and PubMed/MEDLINE, using the following terms: (early AND discharge) OR (length AND stay) AND (postpartum OR postnatal) AND (effect* OR result OR outcome). Content analysis was used to identify and summarise the findings and methods of the research papers. The evidence available is not enough to either reject or support the practice of early postnatal discharge; different studies have reported different outcomes for women and newborns. The need of systematic clinical research is discussed.

County Recorders Electronic Transaction Fees Under the Control of the State Treasurer and the Iowa County Recorders Association, Auditor of State's Report for the Period July 1, 2003 through September 30, 2005

County Recorders Electronic Transaction Fees Under the Control of the State Treasurer and the Iowa County Recorders Association, Auditor of State's Report for the Period July 1, 2003 through September 30, 2005

State Government E-Commerce Study Encouraging the Use of Electronic Financial Transactions With the Citizens of Iowa, January 20, 2006

This report was produced in compliance the 2005 Iowa Acts, Chapter 52 passed by the Eighty-First General Assembly, Session One (2005), requiring that it be submitted to the General Assembly by January 20, 2006. The legislative language mandating the report reads as follows: “It is the intent of the general assembly to encourage the use of electronic transactions with regard to the state's dealings with the citizens of Iowa and other persons. The department of administrative services shall develop recommendations, including proposed legislation, to encourage the use of electronic commerce, including the acceptance of credit card payments, with regard to transactions involving the state. The department shall consult with the state treasurer, state entities currently accepting credit card payments, and any other state entities identified as considering the acceptance of credit card payments when developing the recommendations. The department shall deliver a report to the general assembly by January 20, 2006, including any recommendations, proposed legislation, and other related information, including cost information associated with credit card payments.”

Traducció d'un text tècnic sobre sistemes d'enllumenat: Erco. Einkaufswelten

L’objectiu del present treball és la traducció i l’anàlisi d’una publicació tècnica especialitzada sobre sistemes d’enllumenat, els quals han adquirit una rellevància notable, tant des del punt de vista arquitectònic de l’edifici, com des de la tecnologia de control lumínic que afavoreix l’estalvi energètic.

[Archives de la Parole]. , Special text in santali / [Sir George Grierson], éd. ; Linguistic survey of India ; Voix parlée, homme

[Traditions. Asie. Inde. Chotā Nāgpur]

[Archives de la Parole]. , Special text in mundari / [Sir George Grierson], éd. ; Linguistic survey of India ; Voix parlée, homme

[Traditions. Asie. Inde. Chotā Nāgpur]

[Archives de la Parole]. , Special text in Ho [i.e. hō] : (poésie) / [Sir George Grierson], éd. ; Linguistic survey of India ; Voix parlée, homme

[Traditions. Asie. Inde. Chotā Nāgpur]

Técnicas de Data e Text Mining Para Anotação de Um Arquivo Digital

O presente trabalho cujo Título é técnicas de Data e Text Mining para a anotação dum Arquivo Digital, tem como objectivo testar a viabilidade da utilização de técnicas de processamento automático de texto para a anotação das sessões dos debates parlamentares da Assembleia da República de Portugal. Ao longo do trabalho abordaram-se conceitos como tecnologias de descoberta do conhecimento (KDD), o processo da descoberta do conhecimento em texto, a caracterização das várias etapas do processamento de texto e a descrição de algumas ferramentas open souce para a mineração de texto. A metodologia utilizada baseou-se na experimentação de várias técnicas de processamento textual utilizando a open source R/tm. Apresentam-se, como resultados, a influência do pré-processamento, tamanho dos documentos e tamanhos dos corpora no resultado do processamento utilizando o algoritmo knnflex.