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The Raman spectra of Eu3+ doped Gd2Zr2O7 nanopowders were measured. We registered three phonons at 177 cm−1, 268 cm−1, and 592 cm−1, as well as their overtones at 354 cm−1, 445 cm−1, 708 cm−1, 1062 cm−1, 1184 cm−1, ∼1530 cm−1, and ∼1720 cm−1. The phonon at 592 cm−1 is known to be characteristic for Gd2Zr2O7 fluorite-type structure; however, the other two have not been registered so far. We found that the position of the newly detected phonons agrees well with the observed electron-phonon interaction. On the other hand, the registered multiphonon processes were a consequence of miniaturization that further induced changes in electronic structure of Eu3+ doped Gd2Zr2O7 nanopowders.

In this paper we describe the synthesis and characterization of the YVO4:Eu3+ nanopowder. The material was prepared using simple solution combustion synthesis. X-ray powder diffraction (XRD), scanning electron microscope (SEM), Raman and photoluminescence (PL) techniques were used to confirm and characterize the prepared material. The time resolved analysis of emission spectra was achieved by using the streak camera system. Beside luminescence lifetime of slow decayed transitions we also measured their rise time and lifetime of fast decayed transitions. We also determitied the excitation spectra of this nano material. Results of our analysis prove that YVO4:Eu3(+) nanopowder is appropriate material for various optoelectronic devices. (C) 2016 Elsevier Ltd. All rights reserved.

Indium selenide belongs to layered III–VI semiconductors with highly anisotropic optical and electronic properties. Energy gap of 1.32 eV makes this material very attractive for solar energy conversion. We investigated the influence of 1% 3-d transition metals M=Mn, Fe, Co, Ni, used as dopants, on energy levels of InSe:M in the range 1.4–6.5 eV and especially in the range of energy gap

The nanopowders of (ZnO)1–x(Al2O3)x, where x ranges from 0 to 0.7, were obtained by two chemical methods: the co-precipitation/calcination and hydrothermal synthesis. The first assessment of structural and optical properties of the obtained nanopowders was undertaken by the SEM, XRD, Raman and far-infrared spectroscopy, which was followed by the photoluminescence spectroscopy at room temperature. The obtained far-infrared reflectivity spectra were analyzed using the fitting procedure. The dielectric function of ZnO–Al2O3 nanopowders was modeled by the Maxwell-Garnet formula under the assumption that the nanopowders are a mixture of homogenous spherical inclusions in air. The combined plasmon-LO phonon modes (CPPM) were observed in the far-infrared reflection spectra. The photoluminescence spectra contain emissions related to the presence of ZnO, ZnAl2O4, and AlOOH phases in the nanomaterial, which is in agreement with the results obtained by other experiments.

In this paper we present photoluminescence measurements of CdSe nanoparticles embedded in transparent glass. Sample is prepared using an original technique, which combines both heat treatment and ultraviolet laser irradiation. Photoluminescence spectra displayed one main emission band at 2.14 eV. We identify this bands energy as basic interband transition in CdSe nanoparticle. We calculated energy of basic (1sh–1se) transition in spherical CdSe quantum dot (QD), within infinite potential barrier, in effective-mass approximation. On the basis of this model, average radius of synthesized CdSe QDs is about 3 nm, which is in consistence with AFM measurements and UV–VIS absorption measurements.

The interest in thorough description of Zn 1– x Mn x GeAs 2 arises from its suitability for application in the field of non-linear optics. The room temperature far-infrared reflectivity spectra of single crystals Zn 1– x Mn x GeAs 2 , where 0 ≤ x ≤ 0.078, were measured in the spectral range from 80 cm −1 to 500 cm −1 . The spectra were analyzed by fitting procedure using a dielectric function which includes interaction between a plasmon and two different phonons. The detected phonons are in excellent agreement with the theoretical predictions. The MnAs cluster phonons are detected, as well.

Squamous cell carcinoma is a morphologically heterogenous neoplasm of specific histologic entities involved in human papillomavirus infection. The condylomatous types of squamous cell vulvar carcinoma, caused by HPV-16, most often manifest as exophytic papillary tumors mimicking condylomas.

dHAND and eHAND are basic helix-loop-helix (bHLH) transcription factors expressed during embryogenesis and are required for the proper development of cardiac and extraembryonic tissues. HAND genes, like the myogenic bHLH genes, are classified as class B bHLH genes, which are expressed in a tissue-restricted pattern and function by forming heterodimers with class A bHLH proteins. Myogenic bHLH genes are shown not to form homodimers efficiently, suggesting that their activity is dependent on their E-protein partners. To identify HIPs (HAND-interacting proteins) that regulate the activity of the HAND genes, we screened an 9.5-10.5-day-old mouse embryonic yeast two-hybrid library with eHAND. Several HIPs held high sequence identity to eHAND, indicating that eHAND could form and function as a homodimer. Based on the high degree of amino acid identity between eHAND and dHAND, it is possible that dHAND could also form homodimers and heterodimers with eHAND. We show using yeast and mammalian two-hybrid assays as well as biochemical pull-down assays that eHAND and dHAND are capable of forming both HAND homo- and heterodimers in vivo. To investigate whether HAND genes form heterodimers with other biologically relevant bHLH proteins, we tested and show HAND heterodimerization with the recently identified Hairy-related transcription factors, HRT1-3. This finding is exciting, because both HRT and HAND genes are coexpressed in the developing heart and limb and both have been implicated in establishing tissue boundaries and pattern formation. Moreover, competition gel shift analysis demonstrates that dHAND and eHAND can negatively regulate the DNA binding of MyoD/E12 heterodimers in a manner similar to MISTI and Id proteins, suggesting a possible transcriptional inhibitory role for HAND genes. Taken together, these results show that dHAND and eHAND can form homo- and heterodimer combinations with multiple bHLH partners and that this broad dimerization profile reflects the mechanisms by which HAND genes regulate transcription.

A diagnostic and therapeutic approach in the identification of malignant lesions and the types of HPV in 11 patients with gigantic condylomatous vulvar protuberances is presented. Different histological types of squamous cell vulvar carcinoma have been found in 8 (72.7%) cases: condylomatous (4), verrucous (3) and basaloid type of the carcinoma (1). HPV type 16, confirmed in 5 cases, was most often present (4 condylomatous and 1 basaloid carcinoma types). Other types of HPV such as HPV-6 was detected in 3 cases of verrucous, type 11 in 2 cases of verrucous and condylomatous carcinoma and type 18 in 1 case of condylomatous carcinoma. Radical vulvectomy followed by bilateral inguinofemoral lymphadenectomy was performed in 4 patients with condylomatous carcinoma, hemivulvectomy in basaloid carcinoma whereas wide local excision was performed in the verrucous type of carcinoma. No patient died except 1 with condylomatous carcinoma in whom 6 positive lymph nodes were detected after the primary operation. The patient died 4 years later following 3 excisions of local recurrences.