Here we show that replicative senescence in normal human diploid IMR90 fibroblasts is accompanied by altered expression of a set of microRNAs (miRNAs) (senescence-associated miRNAs), with 14 and 10 ...miRNAs being either up or downregulated (>2-fold), respectively, in senescent with respect to young cells. The expression of most of these miRNAs was also deregulated upon senescence induced by DNA damage (etoposide) or mild oxidative stress (diethylmaleate). Four downregulated miRNAs were part of miRNA family-17, recently associated to human cell and tissue aging. Moreover, eight upregulated and six downregulated miRNAs mapped in specific chromosomal clusters, suggesting common transcriptional regulation. Upon adoptive overexpression, seven upregulated miRNAs induced the formation of senescence-associated heterochromatin foci and senescence-associated β-galactosidase staining (P<0.05), which was accompanied, in the case of five of them, by reduced cell proliferation. Finally, miR-210, miR-376a(*), miR-486-5p, miR-494, and miR-542-5p induced double-strand DNA breaks and reactive oxygen species accumulation in transfected cells. In conclusion, we have identified a set of human miRNAs induced during replicative and chemically induced senescence that are able to foster the senescent phenotype by prompting DNA damage.
Micro-Raman spectroscopy of FeTe and superconductor Fe(SeTe) films was used to investigate the compression of the lattice which is a typical feature of chalcogenide films. The lattice strain has a ...strong influence on their electrical, magnetic and superconductor properties. In cases where spin-orbit coupling is non-negligible, an energy split of the 3d orbitals of the Fe atoms that removes the spin energy degeneracy could be generated. This leads to unconventional light scattering mechanisms involving single-magnon excitation. For this reason, we conducted a thorough investigation of FeTe and superconductor Fe(SeTe) films by using visible micro-Raman spectroscopy over a large temperature range. The Raman band at about 1520 cm−1 featured by the FeSe0.5Te0.5 films was assigned to the single-magnon scattering, while the Raman response of FeTe films was ascribed to more conventional two-magnon scattering mechanisms. The temperature dependence of the single-magnon Raman scattering was investigated in the temperature range from 15 K to 295 K, enabling information to be obtained on the influence of spin fluctuations on the magnetic order.
•Influence of lattice strain on Raman response of FeTe and superconductor Fe(SeTe) chalcogenide films.•Temperature dependence of non-phononic Raman features related to magnon excitations.•Single-magnon Raman scattering in Fe(SeTe) films, allowed by the compressive internal forces acting on the crystal lattice.
Single-photon avalanche diodes (SPADs) in the CMOS technology are very attractive solution for photon detection due to the excellent timing resolution achievable. Unfortunately, such devices suffer ...from large values of the dark count (DC) pedestals. In this paper, we analyzed a test chip containing SPADs with different layouts, implemented in the 150-nm CMOS technology. The behavior of such devices has been investigated after proton irradiation. It is observed that, after irradiation, the DC rate switches between two or more discrete levels, phenomenon known as random telegraph signal (RTS). The effect is related to the density and distribution of defects in the semiconductor lattice. RTS characteristics have been studied as the function of both temperature and bias voltage. Discussion of results and main hypotheses on defect types responsible for RTS are reported.
Highlights • A novel hysteroscopic technique for metroplasty, the “ H ysteroscopic O utpatient M etroplasty to E xpand D ysmorphic U teri (HOME-DU technique)” was evaluated. • The study was conducted ...on 30 infertile women with dysmorphic uterus (T-shaped and tubular-shaped/infantilis uteri) – as diagnosed by office hysteroscopy and three-dimensional trans-vaginal ultrasound – who underwent the HOME-DU technique. • Our data seem to support the safety and efficacy of such outpatient technique in order to improve the volume and shape of dysmorphic uteri. • The improvement of the uterine cavity volume and morphology may offer new approaches in increasing reproductive outcomes.
The electronic properties of an infinite row of freestanding, aligned side-by-side, pentacene molecules are derived as a function of the intermolecular overlap integral and the chemical potential ...shift. We use a semiclassical approximation and a first principles tight binding method to obtain conductance and mobility of this one-dimensional crystal as a function of temperature and gate voltage. For two values of the intermolecular overlap, energy bands show a metallic behavior. For all the other values, a bandgap is present and evolves with the intermolecular overlap following a typical modulation. The magnitude of the scattering parameters estimated by the observed conductivity is coherent with the existing literature values. These findings could be relevant for the implementation of organic-based sensors.
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