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A theory of two-photon absorption is presented that addresses the formation of spectral shapes taking the vibrational degrees of freedom into account. The theory is used to rationalize the observed differences between the spectral shapes of one- and two-photon absorption and it is found that the main cause of these differences is that the two-step and coherent two-photon spectral bands are different even considering a single final state.

Background: Nasopharyngeal carcinoma (NPC) is frequently associated with Epstein-Barr virus (EBV). The incidence of NPC in Western countries is lower than in the Far East, and EBV latency in NPC [...]

High-resolution x-ray photoelectron emission (XPS) and near-edge x-ray absorption fine structure (NEXAFS) spectra of naphthalene are analyzed in terms of the initial state chemical shifts and the vibrational fine structure of the excitations. Carbon atoms located at peripheral sites experience only a small chemical shift and exhibit rather similar charge-vibrational coupling, while the atoms in the bridging positions differ substantially. In the XPS spectra, C-H stretching modes provide important contributions to the overall shape of the spectrum. In contrast, the NEXAFS spectrum contains only vibrational progressions from particular C-C stretching modes. The accuracy of ab initio calculations of absolute electronic transition energies is discussed in the context of minute chemical shifts, the vibrational fine structure, and the state multiplicity. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Theoretical analysis of high-resolution C(1s) near-edge absorption and X-ray photoionization spectra of the free biphenyl molecule is presented to allow an assignment of the observed spectral features. Results are compared to benzene and naphthalene to detect the influence of the molecular structure on the core excited state.

Specific language impairment (SLI) is a psychiatric condition with a complex etiology and a substantial genetic basis that affects children's verbal communication abilities. In this study, we examined the expression of five different human endogenous retrovirus elements (HERVs) in a cohort of 25 children with SLI and 25 healthy children in the control group. Human endogenous retrovirus elements, a diverse group of repetitive DNA sequences, can potentially cause considerable genetic heterogeneity. They had been integrated in the genome of our ancestors throughout evolution and now consist of about 8.0% of the human genome. Several HERV loci are transcribed in various cell types. Their expression in peripheral blood and in the brain is altered in many neurological and psychiatric diseases. To date, HERV expression profiles have never been studied in patients with SLI. This study aimed to elucidate differentially regulated human endogenous retroelements in peripheral blood of children with SLI, in comparison with healthy controls, through quantitative reverse tran-scription-polymerase chain reaction (qRT-PCR) methodology. Our results show that two genes: HERV-K (HLM-2) gag and HERV-P env were expressed at lower levels in the blood samples from SLI children in comparison with those in the control group.

Circulating microRNAs (miRNAs) are emerging as promising diagnostic biomarkers for autism spectrum disorder (ASD), but their usefulness for detecting ASD remains unclear. Nowadays, development of promising biomarkers for ASD remains a challenge. Recently, dysregulation of the miRNAs expression in postmortem brain tissue, serum and peripheral blood, have been associated with ASD. Circulating miRNAs are known to be secreted by a number of different cells and can interpose delivery of information into receiver cells, thus affecting their functions. Based on this fact, it is supposed that serum miRNAs could be a novel class of biomarkers for prognosis or diagnosis of pathological disorders including ASD. In the current research, we investigated whether the expression patterns of circulating miRNAs showed dysregulation in subjects diagnosed with ASD. Expression levels of serum miR-328-3p and miR-3135a were analyzed by quantitative reverse transcription polymerase chain reaction (qRT-PCR) method of subjects diagnosed with ASD in comparison with healthy control subjects. Our data showed that miR-328-3p and miR-3135a were substantially down-regulated in ASD patients than in those of healthy control subjects. Moreover, target gene analysis of altered serum miRNAs displayed that these molecules targeted 162 genes denoted as unique validated targets in the miRWalk database, 71 of which appear to participate in biological pathways involved in synaptic pathways and neurodegenerative condition such as Alzheimer, Huntington and Parkinson diseases. Finally, the results strongly suggested that dys-regulated serum miRNAs might be involved in molecular pathways associated with ASD and miR-328-3p and miR-3135a have the potential to be promising novel biomarkers for ASD.