Publications by authors named "Vescovi G"

We present the characterization of a pn-junction GaAs nanowire. For the characterization, current-voltage, electron-beam-induced current, cathodoluminescence, and electron holography measurements are used. We show that by combining information from these four methods, in combination with drift-diffusion modelling, we obtain a detailed picture of how the nanowire pn-junction is configured and how the recombination lifetime varies axially in the nanowire.

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This study compared children's and mothers' digital media use and mothers' mental health in two samples: one accessed before (Group 1; N = 257; M = 33.18 years; SD = 4.79) and the other accessed during (Group 2; N = 256; M = 33.

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COVID-19 pandemic has become a significant international public health problem. In addition to dealing with the pandemic's impact on mental health, parents need to cope with specific changes in their routines caused by social distance measures. This study aimed to investigate common mental disorders (CMD) symptoms in Brazilian parents during the COVID-19 pandemic and its associated factors.

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Article Synopsis
  • Space power systems need lightweight and efficient solar panels to operate in harsh space conditions for long durations.
  • Current high-efficiency solar cells face limitations due to the need for heavy radiation shielding, which reduces their power-to-weight ratio.
  • III-V nanowire-array solar cells show significantly better radiation performance than traditional planar designs, potentially allowing for lighter solar cells with improved longevity and efficiency in space.
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We report on the direct observation of the diffusion of carriers in graded InGaN/GaN quantum wells in a nanowire. By probing the local dynamics at the nanoscale, along the wire for different temperatures between 4 and 250 K, we conclude that this diffusion process is thermally activated. In addition, the analysis of the cathodoluminescence lifetime for different temperatures shows that the carrier motion is isotropic and does not follow the indium gradient.

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We report on the electron beam induced current (EBIC) microscopy and cathodoluminescence (CL) characterization correlated with compositional analysis of light emitting diodes based on core/shell InGaN/GaN nanowire arrays. The EBIC mapping of cleaved fully operational devices allows to probe the electrical properties of the active region with a nanoscale resolution. In particular, the electrical activity of the p-n junction on the m-planes and on the semi-polar planes of individual nanowires is assessed in top view and cross-sectional geometries.

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X-ray nanobeams are unique nondestructive probes that allow direct measurements of the nanoscale strain distribution and composition inside the micrometer thick layered structures that are found in most electronic device architectures. However, the method is usually extremely time-consuming, and as a result, data sets are often constrained to a few or even single objects. Here we demonstrate that by special design of a nanofocused X-ray beam diffraction experiment we can (in a single 2D scan with no sample rotation) measure the individual strain and composition profiles of many structures in an array of upright standing nanowires.

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Pregnancy, motherhood, and HIV infection in adolescence are events with relevant biological, psychological, and social implications for mothers, their babies, and families. Our study aimed to identify protective factors of the experience of pregnancy and motherhood among young mothers living with HIV, highlighting similarities and differences. A mixed method multiple-case study was conducted with three young primiparous mothers (ages 17 to 19 years), whose babies were 4 to 6 months old.

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We report on the demonstration of MOVPE-grown single nanowire InGaN/GaN core-shell light emitting diodes (LEDs) with a transparent graphene contact for hole injection. The electrical homogeneity of the graphene-contacted LED has been assessed by electron beam induced current microscopy. By comparing graphene-contacted and metal-contacted nanowire LEDs, we show that the contact layout determines the electroluminescence spectrum.

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Phospholipid-sensitive, Ca++-dependent protein kinase activity was investigated in the cytosol of melanoma cells. A protein kinase system was partially purified, and enzyme activity was found to be modulated by palmitoyl-carnitine. In order to link the actions of palmitoyl-carnitine on phospholipid-sensitive protein kinase activity and the already reported role of protein kinase C in cell division, we studied the action of palmitoyl-carnitine on melanoma cell growth by measuring colony forming ability in a soft agar culture system.

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Somatomedin activity is often measured by 35SO4 uptake in pelvic chick embryo cartilage. This assay gives good results when the somatomedin activity is measured in serum, but often gives uninterpretable results for purified somatomedin. An ultrafiltrate (UF 1000) obtained from human normal serum, added to the incubation medium allows measurement of biological somatomedin activity even when somatomedin is highly purified.

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After labelling of human and ovine prolactine by the lactoperoxydase method, each prolactine shows at least three molecular forms : amorphous aggregates of large molecular weight, one dimere (M.W. no.

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The authors have studied by gel chromatography and radioimmuno assay, the molecular forms of prolactine in the serum of normal lactating women and in serum of three subjects having an hypophyseal tumor. 1. In the normal women, one find two pics of prolactine : one migrating like the monomere (M.

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The authors have shown an heterogeneity of the ovine prolactine molecule after labelling with iodine 125. As well with chloramine T as with lactoperoxydase, it appears three molecular species which react with the immune serum antiprolactine (I.S.

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